BMW 3.0CS - Pulling motor / install a 3.5 Liter
Once you see one - what do you look at?
(We need help here from the experts)
Pull the sparkplugs. Are they all the same in appearance. Do the ceramic tips have a tan color.
Pull the cam cover. What is the general color and texture. Golden glow. Even coating. No deposits.
(Slimy, gunky, dark brown, dark black are signs of poor oil maintenance)
Feel the cam lobes. With your trusty fingernail, scratch across the high part of a lobe, especially number one
cylinder. You should not feel any ridges. If you do the cam is shot.
Look in the intakes They should be spanky clean and free from oil. The aluminum should gleam.
Look at the exhausts Should be an even dull flat black. No white powder look. No oil. All even.
Look in the water ports They should be grunge free. Light white deposits indicate regularly changed antifreeze.
There should be no traces of oil.
Check head gasket There should be no oil oozing from it. Look over starter area.
Check oil pan Leakage should be minimal. Check residue at drain plug.
A majority of time will be pre prep. Getting ALL the needed gaskets, seals, fluids, cleaning solutions, gloves, tools,
parts, etc. in advance is the way to go. You don’t want to be chasing down things while you are working. It wastes A
LOT of time! We can’t stress the need to get all NEW gaskets/seals for the engine. Changing them while the motor is
out is easy and will save you considerable work after the motor is in (DunRite raises his head here…). BMW doesn’t
sell engine gasket/seal sets, so you’ll need to get them individually. The list is long, but most all of the gaskets are
the same for all the years up to 88 (We think) for both the 2.8 and the 3.5. They are the same block. The Mobile
Traditions CD is VERY useful here. It not only lists part #’s but also list bolt sizes and lengths. (Sean is working on a
Okay…. So now you’ve got all the goods, engine, gaskets, hoist, etc…. We used two cement blocks under the front
tires to get the car high enough to get under it. It’s pretty stable, jack stands are also recommended as an additional
safety item. Chock the rear wheels. A lift would be nice, but hey….. a driveway works too…
The Ongoing Saga .... The next thing I would tackle, and it is a bit disputed by Peter and others, is to remove the
transmission. In my case it’s a five speed. If your hoist has a tilter cradle, then tranny removal may not be required.
Every engine swap I’ve done, I have removed the tranny first.
This issue ended up being the most controversial issue of all during each of our transplants. We will walk you
through the highlights of yanking that nasty engine out of that teeny space and shoe horning it back in.
When PC did his engine swap he decided to keep the tranny on the engine, disconnect the driveline and pull the
whole engine/tranny assembly out. PC had a conventional engine hoist with chain bridging the water pump bracket
and the bellhousing point. The car was jacked up on jack stands approximately 16” behind the front wheel wells. He
also had the rear on jackstands at 12”. Even with engine at an extreme upward tilt it was a struggle to get the tranny
to clear the transmission hump at the firewall whilst keeping the pulleys from decimating the AC Condenser. As a
result PC tore up the foil covered black rubber acoustics at the firewall.
For Sean’s car, PC was convinced that we should leave the tranny in place, undo the 4 – 19mm transmission bolts,
and pull the engine/bell-housing out. Enhancing this wonderful labor saving method was the discovery of the magic
“C” box wrench for ease of tranny top left bolt removal. However, due to limited clearances fore and aft, we could not
slip the engine free from the tranny input shaft. Thus our extraction angle was limited and the pulleys jammed the top
of the radiator bulkhead. As a last ditch effort Sean unbolted the pulleys and the harmonic balancer and we just
barely lifted the engine free. We also tore Sean’s black rubber acoustics up. Sean was not at all impressed with
Peter’s in depth knowledge.
The optimum but most labor intense method is to undo the tranny at the driveshaft, undo the shift linkage, undo the 4
– 19mm tranny bolts, drop the cross member, and slide the tranny out. Then, undo the bolts securing the
bellhousing to the engine and pull the bellhousing out. At that point you should be able to lift the engine straight up
and out of the car. By the way, your chain and hoist need to hooked up throughout this procedure.
A variation on this method is to leave the bellhousing on, without the input shaft it should be easier to get a decent
upward angle on the engine.
If you have a high garage, tall jackstands, and a decent hoist, the engine/tranny combo is still workable.
Unfortunately most of the time consuming labor is in disconnecting the drive shaft, the gear shift, and the tranny
Humbled, PC did not argue with Sean on dropping the engine in. Engine only, no bellhousing, no tranny, virtually a
straight drop into the engine bay. Even with this simplicity, you have to wrestle the AC pump and the engine mounts
into exact position, a difficult task. With the engine in position, bolting up the spanky clean bellhousing was a
breeze. The tranny is heavy and difficult to maneuver into position. The secret is to rotate the drive flange while
pushing the input shaft into the pilot bearing. Secure the 4 nuts and connect the rear of the tranny.
When PC did his car, He installed the engine/tranny as one unit. The time and energy spent jockeying and
repositioning the engine to get it to fit in just right (3 times) was far greater than the Sean approved method
We note that some bulletin posters claim that they can undo the bellhousing bolts while leaving the tranny in place.
This greatly reduces the labor required to pull the engine free. We tried several combinations of universals,
extenders and 12” flex drives with poor results. Hence the above recommendations for fellow swappers with limited
tool collections and minimal transmission R & R experience.
* Here we’d like to drop in a note on hardware storage… A box of Ziplocks comes in handy here. And some type of
tagging. Paper tags, printed labels, etc. This will make the re-assembly process much easier. Take the time to do it, If
not you’ll be referring to the Parts CD later to find the right size nuts/bolts.
Remove the 4 bolts that secure the brackets to the car. (Not hood) Undo the 2 bolts that hold the elbow limit
braces. Disconnect the window washer hoses.
Remove the hood and store it in a safe place. You don’t want it falling over.
Disconnect the battery, remove it, and store it.
Drain Coolant / Remove radiator
Drain the coolant. There is no petcock on these radiators so it can be messy. Remove a temp sensor at the lower
hose to drain radiator. Undo 19mm bolt at passenger side of block beneath #6 sparkplug to drain block.
The plastic fan shroud has 2 sheet metal screws at top and tabs at the bottom. Undo screws. There is a 10mm
screw at passenger side bracket. Remove bracket. Undo top and bottom hoses. Undo wire spade connectors at
thermo sensors near lower hose. Radiator should pull upward with some jiggling. Remove shroud. Place a piece of
masonite where the radiator was to protect the condenser from being hit (if you have A/C).
Label Injection Wiring Harness Points / Removal
Here is where you really want to pay attention and label whenever you can.
There are really not too many connections on the motor. The biggest problem is that all the wires are the SAME
COLOR for the injection harness.!!! We snapped some pics before doing this… Might be useful later?
Be sure to label all of the thermo sensor wires.
Label Chassis Wiring Harness Points / Removal
Oil Pressure sender, starter, alternator, ground at thermostat cover, ignition wire at distributor, transistor box multi-
plug, coil, AC connector. For 79 the front and rear runners had to be removed to undo the wire harness.
Chart Manifold hoses
Make a diagram of all manifold vacuum hoses and cold start connections. (Aux air valve) Even better, label the
Remove them. Check them for age and cracks.
Mr. Dun Rite: Take pictures of them before disassembly. You will REPLACE them later.
Remove AFM / Removal
Remove air cleaner assembly, AFM multi plug , and AFM. Take the rubber bellows off the throttle body.
Undo Throttle Linkage
Undo pop-on connectors at fire wall and from bell-crank to throttle body. Note the position and orientation of the rods.
Remove Throttle Body
Undo 4 nuts 10mm. Cut the 2 small water hoses and undo crankcase vent hose from cam cover. Doing so allows
easy access for disconnecting the plastic injector plugs. Disconnect the throttle position plug connectors. Be sure
to label them. Idle & WOT.
Remove the accelerator rod.
Remove Injection Wire Harness
Remove the plastic thermo and injector plugs. We found that a “pick” type tool works well for this. Be prepared to
catch the clips as they fly… (spring steel) Cut wire ties at firewall. Work your way from the front of the motor to the
Disconnect and label the wiring from the engine main harness along the valve cover. This includes the injector wires,
WOT (already disconnected from previous step), cold start injector sensor, coolant temp sensor, oil pressure switch,
etc. The locations of some of the sensors vary depending on the model year you are starting with. Drape harness on
windshield, secure with wipers.
Pull computer plug from glove box if installing Motronic. PC tried for fun and could not figure how it pulls out - so
Remove Chassis Wire Harness
Undo starter wires, undo alternator wires, undo dipstick wire holder, undo wire stays at intake runners. Secure out of
the way on the wheel well.
The wire harness from the distributor/ignition module can be routed onto the top of the radiator support and out of
the way. You may want to tuck it behind the masonite protecting the condenser.
Remove Fuel Lines
Remove the fuel lines from the pressure regulator and the rear of the fuel rail. Label them for re-installation.
Remove and label the vacuum lines from the pressure regulator.
Remove the fuel line from the cold start injector.
Remove Brake Booster Hose
We had to cut this hose near where it attaches to the log manifold. Be careful to preserve this hose. It is difficult to
find a replacement.
This is special “anti collapse” hose so don’t skimp on replacement! We’re talkin’ brakes here!
Map Coolant Hoses
Coolant hoses vary from year to year. Pay special attention to the heater formed hoses and connections.
This is especially important if you have the “Jules Verne” plumbing under the intake pipes like Sean’s car has(1979).
Remove All Coolant Hoses
Remove the heater hoses that go to the heater unit.
Remove the coolant hose from the filler (expansion) tank.
If stuck, cut them off especially at the firewall and the smaller hoses.
Save all hoses and label for the hunting and gathering of new replacement hoses.
Power Steering Pump
Remove with 3 -17mm bolts. It stays on the chassis. Wire out of the way.
Remove top adjuster bolt and 2 bottom 17 MM bolts. It stays with the chassis. Disconnect the wire if you have not
Remove the belts. A/C, P/S, Alt. You may want to mark them so you know which ones are for what later. (Of course
you’ll want to put on new ones! Mr. DunRite)
Remove Cooling Fan
With radiator out, remove fan from water pump. 4 -10mm bolt. Remove the cooling fan and fan clutch. There are two
different styles here. Sean had the older style pump with 1 – 10mm bolt thru the fan clutch. (This will determine which
way you may want to go when you replace the water pump. More on this later.)
Set engine at Cylinder #1 TDC (See Timing Marks on Damper). Release 10mm clamp bolt. Distributor spins
counterclockwise up and out.
Now would also be a good time to remove the cap, Ignition wires, and the distributor. Take notice on the position of
the vacuum advance on the distributor and also observe the rotation of the rotor as you remove the distributor. This
will help on reinstall. Tape over the dist. hole with duct tape. Don’t want any “smeg” going in there.
(“smeg”- besides the biological stuff, it is also the stuff that is covering your engine at this point. Grease/Grime/Dirt = ”
Chain Engine to Hoist
Using the front hoist tab and the hole in the engine block above the starter, hook or (better) bolt a chain. If these
locations aren’t accessible, you’ll need to find suitable locations to connect to the motor. Be sure you are not bending
or rubbing any crucial parts when you lift. Set chain so it does not press against the fuel rail.
Once you get the chain attached, you should be able to get the hoist to lift it almost straight out of the engine bay.
You may want to have a slight tilt UP at the front of the motor. You should have enough space to get the motor out
with the clutch still on, but with the bellhousing still on you’ll have a VERY tight squeeze (See memo on tranny or not).
Another thing to think about, make sure your hoist can be fully extended as you’ll need to lift the motor very high to
get it over the front of the car without lowering it off the blocks.
Undo Engine Mounts
Undo 4 - 17 MM nuts top and bottom.
Take a minute, maybe stop and have a beer, and check that all wires, hoses, etc. are disconnected, labeled and out
of the way.
Under the car ...
There are several different tranny/engine removal sequences available for your home mechanic pleasure. We will go
with the most labor intense/ easiest engine yank. (In Sean’s own words)
(By the Sean feels very strongly about PULLING the TRANNY FIRST!)
Undo 3 nuts from rusty manifold studs from under the car. Be gentle so you do not damage the studs. Use liberal
amounts of Liquid Wrench starting a week prior to removal. Undo the hanger above the fuel pump and the rubber
donuts at the rear.
Remove Oxygen Sensor. Remove the Heat Shield.
On Sean’s car the Exhaust system came out in one piece. It was pretty simple to remove but a bit cumbersome to
Undo all rear tranny Connections
Remove the 3 Guibo (Rubber Donut) nuts and bolts. Disconnect the shift levers and remove the shifter. There is a
10mm bolt up high. Remove speedometer cable. Remove the clutch slave cylinder 2 – 13mm nuts and the clutch
hydraulic line keeper at the bellhousing. One 17mm bolt. Remove the reverse sender wires above the clutch slave.
Remove the Tranny
Undo the 4 - 17mm nuts at the tranny to bellhousing. You need a special “C” or “S” shaped box wrench to get this
bitch of a nut loose. Tilt engine up on hoist. Tranny should slide out from bellhousing. The tranny is heavy, so be
carefully of your body and fingers.
The drivers top left nut may be a candidate for a weeks worth of liquid wrench prior to removal.
Undo the Bellhousing
With the tranny out, you now have access to the bolts securing the bellhousing to the engine. Starting at the oil pan,
there are 3 - 10mm bolts that secure the bottom cover plate. More than likely they are covered with crud, smeg, and
slime. There are 17mm bolts at 4 locations and 13mm bolts at 3 locations holding the bellhousing to the engine. The
aluminum bell housing slides right off.
Extract Engine from Bimmer
With a slight upward tilt, whilst wrestling the AC pump out of the way, you should be able to lift the engine up and out
of the bay without interference from the top of the radiator bulkhead.
Boy wasn’t that easy !
It only took three of us, 4 hours to get to this point on Sean’s car. PC’s took 8 as he was “on his own” and it was his
1st time around.
drop_in.jpg (62410 bytes)
Position 2.8 for ease of Access
You will now be removing many more parts from the 2.8 for transfer to the 3.5 than you thought.
Remove the alt. And store.
Remove the brackets for the steering pump, alt, and a/c.
Remove the clutch and discard.
Remove the flywheel. You may need to improvise here to get the bolts out. An air impact wrench will help here.
Remove the exhaust manifold(s). These nuts may need to be soaked with “liquid wrench” in advance.
You’ll probably need to replace these on the 3.5 motor, so don’t worry to much about breaking the studs.
Remove the motor mount flanges from the engine block.
Remove the cold start injector and spacer
Remove the 6 “C” intake runners.
Remove the “log” from the top of the intake.
Remove the injector holddowns. (remember to “bag and tag” the bolts, spacers, washers, etc!)
Remove the injectors, the fuel rail and injector manifold as one unit. Remove all of the coolant hoses. On the 79
engine we removed this, which also led us to the removal of the coolant jacket for the Aux. Air Valve. See the pic as
this one looks like a spider web. This housing also has the temp-time switch and coolant temp sensor. On the 80 and
newer models the Aux. Air valve/sensors are located on the valve cover and thermostat housing respectively. The
coolant piping is different between these years as well. We used the stock setup on re-assembly(for Sean’s 79) so
piping here may need some improvisation.
Remove the dipstick.
Remove the oil filter housing from the block.
Remove the oil pan. Lots of bolt here…
Remove the thermostat
Remove the water inlet housing.
Remove the starter
If you are doing a Motronic conversion, you can skip several of these steps but you still need to move a lot of parts.
Feng1.jpg (75694 bytes)
Front Timing Cases
Upper and Lower
UPPER - Remove the large nut in the side of the lower timing case. It is spring loaded to holds the timing chain
damper. Remove the 6 front bolts from the Upper Timing cover. There are also 2 smaller bolts connecting the upper
cover to the lower, remove these as well. The cover may need a bit of coaxing to get it off (rubber mallet works well
here). The Distributor drive gear is housed in this cover, it should come out of the front of the cam pretty easily.
There may be a bit of tension on this as there is a rubber O-Ring on the drive gear shaft (inside the cam).
LOWER - (Optional) This means you’ll have to remove the harmonic balancer/pulley assembly from the engine. 8 –
13mm bolts. You will have to undo the 325 Ft LB crankshaft “mother” nut. We used an air impact wrench to get this
nut off. There are other ways to remove it, but we think it puts too much unneeded stress on the crankshaft. Use a
gear puller to remove the hub.
Install a new front seal.
Remove the old seal from the lower case. This may require a hammer and punch. Be careful not to “nick” the case.
Using wood blocks to hold the case will help. Insert the new seal, DRY. Use a large socket around the edges of the
seal to hammer it in (tap it in per PC).
Use gasket sealant and place the new timing case gaskets onto the case. Coat both sides, but not the top (where the
upper case meets it) and not the bottom (where it meets the oil pan). Insert and tighten the bolts that don’t have
brackets to be included (this is the reason to LABEL everything…)
Install hub and retighten crankshaft bolt to 325 FtLbs with air impact gun. Don’t forget to wipe a bit of oil on the
rubber part of the seal before putting the case on.
The L Jet & Motronic are very sensitive to engine vacuum which includes the entire sump and head volumes of the
engine. Replacement of the crank seals is an easy procedure to insure 100’s of K miles of vacuum tightness.
uppertiming.jpg (42320 bytes)
front_nut1.jpg (48189 bytes)
Rear Crank Seal
The seal is held by a cast aluminum housing. The seal can be removed with a pick. Check the crank for grooves. If
present, try to locate the new seal wiper on unworn surface. Apply a finger of oil to the seal part touching the crank.
Lightly tap into place incrementally using a piece of wood and small hammer. Try not to deform it. There is also a
spacer ring that may be in there. According to the BMW parts guy we spoke to, that part has been omitted. we didn’t
use it… but that will be your call. You’ll want to remove the oil pan bolts here too. Cut away the old gasket.
If you go the housing route, apply “form a gasket” to all mating surfaces of the aluminum housing to the cast iron
block to insure a vacuum tight installation.
Dunrite! Sean also changed the gasket on the oil seal holder as well. ( This is one part he forgot to get in advance.
Had to run out and get it or we were done for the day. Wasted 3 hours.)
OldOilSeal1.jpg (93133 bytes)
ROilseal1.jpg (91996 bytes)
(L jet specific)
You need to get your flywheel surfaced at a machine shop(remember we are using manual trannys…). They will take
approx. 20 thousandths off. Sean’s required surfacing at the shoulders, thus the 3 pressure plate locating pins had
to be removed. PITA. Replace the pins when done. You may need new ones since you may ruin the existing ones
There is a locating tube at one of the 8 holes. Thread in all 8 -19 mm bolts coated with Loctite. Torque to 73 Ft Lbs
in stages of 10 lbs.. The bolts had a nice feel as we did the last round of torque to73 FT Lbs.
To hold the flywheel when tightening use a flywheel holder (time for a new tool anyway).
Purchase new bolts from the dealer for this critical application.
The Loctite is an important step toward eliminating vacuum leaks in addition to holding the flywheel to the car at
higher RPM’s. (Loctite is an epoxy that cures in the absence of oxygen)
*** Make sure you use both sealant and thread locker on the flywheel bolts. This is a crucial step as if you don’t use
sealant, you will have an oil leak, and think it’s the rear seal. The bolts WILL leak.
fly_holder1.jpg (59351 bytes)
Apply Loctite to outer surface of the Pilot Bearing. Gently tap it into position using some wood and a hammer. We
could not determine the optimum depth to set the bearing at.
Note: We both had donor engines with automatics, hence no existing pilot bearings. Here are three techniques for
removing a pilot bearing that refuses to come out ....
1) rent a removal tool, it looks like a slide hammer, or lock extractor.
2) Fill the space behind the pilot w/ Black Cats, light the fuses and voila! (Wear goggles for this method! And
KEEP YOUR MOUTH CLOSED!)
3) Fill the volume behind the bearing with packing grease. Find a wood dowel that matches the pilot hole take a
hammer and?… (hydraulics)
pilot.jpg (20326 bytes)
Clutch, Pressure Plate
Using the nifty plastic clutch tool, set the clutch plate and the pressure plate on to the flywheel. There are 3 locating
pins for the pressure plate. Thread the 6 – 13mm or (6 mm allen) bolts. Tighten evenly in 4 or 5 sequences till the
pressure plate is snug to the flywheel. Torque to 17 FtLbs. Slide the clutch tool in and out during this sequence to
insure that the clutch disc is evenly centered on the pilot bearing.
Sean and I both used the Sachs “Super Set” clutch kit which comes with everything you need to do a complete clutch
job.. We paid $180.
There may be a 3.5 pressure plate that is a little stronger than the 2.8. Sean is using the 2.8 and it works just fine for
alignment_tool.jpg (42819 bytes)
Timing Marks on
Apply white and yellow paint 2 inches beyond the stainless balls and between the stainless timing balls. This will
make it very easy to find the marks through the bell-housing view port.
paint1.jpg (27624 bytes)
Bolt up your 2.8 steel mounts to the cast iron block bosses. 17mm bolts.
Based on uniformed opinions, all M30 blocks have bolt bosses that will take the E 12 engine mounts. At least thru
Eng_mnts1.jpg (19536 bytes)
The oil pan has to fit the E12 chassis and cross bar. Most later E28s do not fit. Some earlier 733, 633 etc. May fit.
The E28 & E24 oil pans are approx. ½” or 10mm deeper than the E12, they also have better baffles. If your new pan
looks like it might fit, chain new engine on engine hoist and do a trial fit. Replacing the oil pan gasket is infinitely
easier with the pan out of the car... clean it spanky clean.
(this pan is why you want to do a conversion!)
pan1.jpg (57184 bytes)
Oil Pick Up
If using your E12 pan, the oil pick up needs to be transferred from the 2.8 engine. The E12 pick up is approx. ½”
less deep than the 3.5 pick up. The tabs holding it are different from the E12 so you may need to improvise a bit.
There are 3 -10mm bolts that secure it to the oil pump. There is a thin metal gasket that fits between the pump and
pick up. All 10mm bolts.
You will need to remove the 3.5 oil pick up. It is held by 4 bolts on the pump and 2 on a support bracket. Don’t
remove the end cap to take off this support bracket. It is easily bent out of the way to remove the pickup.
Oil_PUs1.jpg (33285 bytes)
Oil Pan Install
Lightly screw all of the 10 mm bolts back in. Starting at the middle (Cylinders 3 & 4) tighten the bolts in a pattern
working outward in both directions to avoid creating any weird stresses in your beautiful aluminum casting. Use
Sealant/gasket cement on the pan gasket. Put the pan back on. Tighten the bolts evenly, and don’t over tighten. If
you crush the gasket too much you may have leaks.
There are different schools of thought for gasket sealing. We both went with coating both sides of the oil pan
gasket. I used copper RTV, Sean used liquid “form a gasket”, we will see whose is better. Avoid applying too much
sealer as it might get stuck in an oil passage. It appears that trying to replace the gasket with the engine in the car is
next to impossible so why worry if a one sided application facilitates future servicing.
Before installing harmonic balancer...
The Alternator, AC Bracket, Power Steering brackets all have bolts thru the lower timing case. The 3.5 balancer
blocks access to the bolts. Secure the bolt for each bracket. Be sure to keep track of the correct bolts. The bolts
through the timing case are all special lengths. 13mm bolts.
The balancer has a locating pin to reference it to the crankshaft TDC. The pulley holes are eccentric (not evenly
spaced). Rotate the pulley until all of the holes align. Install and evenly torque the 8 - 13mm bolts.
The 3.5 balancer is larger than the 2.8. Be sure your engine monger includes it in the deal. We could not get an
opinion it is important to use the 3.5 balancer or not.
Install the AC bracket. 2 -17mm bolts to the block and 2 -13mm bolts thru the timing case.
Engine Diagnostic Sensor
You need the sensor bracket off of the 3.5(due to the larger balancer). One of the bolts also secures the AC Pump
adjusting bracket. One of the bolts is extremely long. 13mm x 45 mm
Fan Pully Engine R&R
Install with new gasket and 4 - 10 mm bolts. We strongly recommend a new water pump. $50
There is a Catch 22 ....
(There two types of fan clutch mounting systems which affect the model of pump that you use. The E12’s have a
single 10mm bolt to secure the fan clutch to the pump. That old style fan clutch costs $125 for replacement. A
newer style fan clutch has a large gland nut that spins onto a large thread on a newer style water pump. New style
fan clutch $75. You will also need a newer style fan pulley, the hole spacing is different. It is vastly easier to remove
& replace when radiator is installed)
Special Conversion Nut
(L Jet required)
There is a special nut that threads onto the end of the 3.5 camshaft with a slot milled to accept the spade end of the
distributor drive. Put the “giant” nut onto the cam. Use a bit of thread lock. Torque to the end of the cam.
32 or 36 mm. It is big. (Cannot remember) We paid $45.
You can use channel locks to grip the bolt. Or go to Sears and get a $20 socket (PC) or a $20 open end (Sean).
Upper Timing Case (L Jet required)
Install the nut, spring, ball and piston for the timing chain damper. Use a good amount of oil on these during
If L-jet, you need to re-use upper timing cover from the 2.8 for the distributor drive. . Put the NEW O-ring onto the
distributor drive and coat with a bit of oil. This O-ring is important for engine oiling (don’t skimp here get a new O
ring!). Insert the drive gear into the cam end. Oil the 2.8 distributor driver shaft and insert into cover. Install cover
with new gaskets at sides and the bottom. Loosely install the 6 – 10 mm side bolts then thread the 2 – 10 mm
bottom bolts. The bottoms were difficult to get threaded. Evenly tighten with a very light torque.
(Note; the L Jet timing cover requires re-use of the 2.8 cam-cover. The front bolt holes are different. The gasket is
different from the Motronic cam -cover.)
Clean up the 2 - 17 mm nuts. Apply oil or graphite. Do not overly tighten the top bolt. (a) Apply dielectric grease to
the electrical connections.
(When you go back to change your starter with the engine in the car you will appreciate this instruction.)
Bolts to block, timing case and bottom of oil sump. Use the 2.8 bracket to insure that all of your 2.8 accessories
(alternator & PS Pump) will fit correctly.
Replace the rubber sleeve if it is worn. Someone mentioned using a polyurethane sleeve that would never wear
out. Secure alternator loosely to the adjusting bracket which you installed prior to the balancer.
The alternator can go in after the engine is in the car. It is easier out of the car. Make sure you use a new bolt of the
correct length because once in the car, adjustment of the alt. position is strictly by braille. The PS pump limits your
access to the adjusting bolt.
Mr. Dun Rite: Replace your alternator with a Bosch rebuild.
Oil Filter Boss
You may need to move your E12 boss over depending on the oil filter set up from your donor engine’s previous set
up. (There has been considerable discussion on this subject, depending on the donor engine used. Up to 1987, you
should be able to use the 2.8 mount directly. After 1988 we’re not sure. If you see any additional oil ports on the
block, write to FirstFives.org list and discuss it there).
L Jet Specific
Install the Injector manifolds and the injector assembly.
Install the runners. Use new paper gaskets at all connections. (We used the single gaskets per port.) Leave all of
the bolts loose so that you can evenly snug down all of the joints (12 in all) evenly with everything aligned. Again you
are preventing vacuum leaks. PC’s has a combo of 13mm nuts and 12mm nuts, Sean’s had all 13mm nuts.
Install the "log" manifold. Do not forget the 2 triangular brackets that keep the log manifold supported. You may need
to bend the supports a bit to get the log into position (see the pic ).
We did not do the Motronic manifold but it bolts right up.
The runners come with stiffeners and with out. The stiffeners interfere with the fuel rail and need to be notched. In
either event, you need to come up with a custom bracket(s) to hold the fuel rail semi rigidly in place.
As noted in GRM the hot set up is to replace the 528 intake runners with runners from a 320i. The longer runners
definitely make a positive difference in the 2000 to 3000 RPM range. Not to mention they look way cooler.
Water Inlet Cluster
This puppy has to go on after the intake manifolds. Clean the port of gasket material. We used the 3.5 housing as
the one from the 2.8 was kind of beat up. It also has all the same sensors in it that are located near the Aux. Air
valve. If I ever decide to change the plumbing on the side of the engine from the 79 version to an 80-81, the wiring
can be moved easily to the sensors in the thermostat housing.
Use a new paper gasket. 3 - 13mm nuts. Note: the top nut secures the diagnostics plug bracket.
It is way easier to install the secondary hoses that mount beneath the manifold and the heater hoses with the engine
out of the car. Leave the heater hoses loose and be careful how you orient the clamps since access in the car is
We replaced all of our hoses with new through out. BMP is the hot set up with a set of all new correct hoses for less
Hot Water Plumbing
L Jet Specific
The L Jet has a hot water loop at the bottom of the throttle body to warm idle air. Most likely this is a smog related
item. The 3.5 blocks do not have a water supply port above the starter like the 2.8 block. The simple solution is get
a plastic “T” from NAPA and cut into the heater supply hose.
Mr. Dun Wrong: This is not an essential fix. PC’s car runs fine at Lake Tahoe in 15 degree weather without the idle
pipe_tap1.jpg (61404 bytes)
Aux. Air Valve Plumbing
Pre 80, the L Jet uses a water temp sensor located beneath the intake manifold runners cobbled into the
heater/reservoir return piping for cold start operation. 80/81 uses an electrically operated idle air control for cold
running that is a much cleaner install. If possible, get the parts off of a wreck.
See The FAQs For Aux Air Valve Descriptions.
Clean the threaded studs with a wire brush. Use new gaskets. Use a graphite anti seize compound on the studs.
(For when you install those new “ extrude honed” ported E28 manifolds later on). Snuggle manifolds onto studs and
secure with bolts.
Sean and I re-used our 2.8 manifolds since we were reusing our 2.8 exhaust systems (and need to meet CA smog
laws). According to all of the bulletins, there are countless horses waiting to be unleashed with a proper 3.5
manifolds or headers, and a free flow exhaust setup.
Mr. Dun Rite: Buy new copper bolts (12 mm) from the dealer. Throw the old ones away. Mr. Dun to the Max,
sweeten up the stud threads with your handy tap & die set before assembly.
exhaust_studs.jpg (55042 bytes)
ex_manifold1.jpg (29771 bytes)
Water Drain Plug
19mm – Bolt into place using a new washer or RTV.
Mr. Dun RiteL: This one is easy to forget.
Heater supply port
At rear of head beneath Rear Cam Cover. Use E12 unit to be compatible with the preformed E12 heater supply
hose. New gasket and RTV, 3- 10mm bolts. Loosely install supply hose. Orient clamp so you can get a screw driver
on it when engine is in car.
This part is impossible to get at with engine in the car. Advanced Braille is required for R&R.
outlet.jpg (9227 bytes)
Rear Cam Cover
There is a stamped metal plate with a gasket and a fiber washer on one 10MM bolt that will leak sooner or later.
Replace the gasket and install the fiber washer on the bolt gasket closest to the exhaust side of the head. This is
also refered to as the “duck” gasket.
Mr. Dun Rite
With engine installed this cover can only be R&R’d by braille. Due to its immediate proximity to the firewall.
rearcover.jpg (46134 bytes)
duck1.jpg (18700 bytes)
There are 2 lines in the Damper for showing TDC. Paint them white or red. This is a good time to turn the engine to
TDC cylinder one for your eventual distributor installation. (After the engine is in the car)
Install alt. / water pump fan belt. Record it’s size. Make sure you have an adequate range of adjustment for the
alternator. Fan belt sizes vary.
The power steering and AC belts go on once the engine is reinstalled.
Mr. Dun Rite: Keep your old fan belts, (or buy new), in your spare tire bay for that one time you wished you had one.
Install to protect valve train.
As noted previously, the L Jet and the Motronic camcovers are not interchangeable. The front bolt hole is located
differently. The 2.8 & 3.5 gaskets are different.
Spark Plug Holes
While easy to get at, check that the spark plug threads are clean, are not cross threaded, and are operating easily.
If not, now is the time to clean them with a tap or heli coil.
Engine Out of Car
Since the engine is out of the car, you might want to clean the engine compartment. Use some type of “gunk”. Protect
the wiring as best as you can from water saturation. Clean and paint any surface rust with rust inhibiting paint. Clean
out the A/C condensor (if the car has a/c of course). Fix any insulation on the firewall that is ripped.
Eng_Bay1.jpg (79801 bytes)
Engine / Transmission
See Notes on your options for engine / tranny combinations for reinstallation. Each has its advantages /
(See Pics Below at "hoist mounting")
Place a piece of plywood to protect the delicate aluminum fins while reinstalling the engine.
Rubber Engine Mounts
Place loosely bolted on the frame mounts. Do not tighten. You will need to be able to move them around during your
engine docking procedures.
Mr. Dun Rite
Install new OEM rubber mounts. I f yours are over 100k miles old, they are most likely shot. (See the Pic above to
compare new to used mounts).
Secure chain to water pump lifting steel tab and to hole in flywheel casing above starter motor. Make sure the rear is
easy to undo with the engine in the car, hand access is limited.
The angle at which you set the engine at depends on tranny or no tranny and how high you have the car jacked up
off the ground. You may have to do 2 or 3 trial attempts to get a successful insertion. The clearances are very tight.
Lower the engine SLOWLY! The tricky part is to get the Motor Mount flanges lined up with the mounts themselves.
The A/C compressor and P/S pump may need to be moved a bit to get the engine all the way down.
Once it’s down correctly, make sure to put the nuts onto the mounts. You don’t want the engine lifting off of the
mounts when working on the tranny reinstall.
Mr. Dun Rite: Cut up a piece of plastic garbage can or similar that matches the profile of the tranny hump. Use it to
protect the foil and rubber shielding while cramming the engine back into place.
drop_in.jpg (62410 bytes)
Eng_Angle1.jpg (81774 bytes)
If you left the bellhousing off now is the time to install it while the engine is at an angle and in the car. (Don’t worry
about the engine resting on the pan, it is very strong and appears to have been designed to do this function.) It has
4 – 17mm bolts and 3 – 13 MM bolts all special lengths. Do not forget the clutch lever and the throw out bearing.
There is a stamped metal crescent moon piece at the bottom of the bellhousing. 3 - 10 mm bolts. Secure before the
engine is in final position for ease of access. The cross member makes access to these bolts difficult.
We made a custom bracket that bolted into the clutch slave location with a long 10 mm bolt that pressed against the
clutch lever bar to keep it tight against the pressure plate. Just some 1 x 1 alum angle drilled and tapped. Otherwise
it flops around and is a real PITA.
bellhousing_view_a.jpg (61415 bytes)
plate.jpg (40692 bytes)
bell_tool.jpg (61083 bytes)
a) In theory you can leave the tranny in position and gently drop the engine so that it slides onto the input shaft.
There is not enough fore and aft clearance to accomplish this easily.
b) If you pulled the tranny, now is a good time to slide the input shaft home while the engine is still at an angle.
c) The tranny is secured with 4 – 17mm bolts. The dreaded bear of tranny world is the driver side top left bolt.
Gertrag threw too many casting fins for any access. The remedy is the magic "S" or "C" wrench(es). (See Pics above
in "Remove the Tranny Section).
tranny_under_car.jpg (61624 bytes)
Temp. Tranny Support
You will need to support the rear of the tranny. Reposition your jack to hold it until you are ready to install the cross
Before dropping the engine to the mounts, position the AC pump in the correct position. Ease the engine down until
you can set the 2 - 17mm bolts that secure the bottom of the pump. Install the electric clutch wire.
This step is so easy to write about! Wrestling with the heavy AC pump is a definite PITA.
Engine Mounts ***
With the above done, lower the engine onto the mounts, you may have to jiggle the rubber engine mount studs to
(You did leave them loose?)
Check the engine and tranny for clearances and alignments before dropping all the way onto the mounts. 17mm
nuts. 4 total.
Rubber Donut (Guibo)
Set the three 17mm bolts that secure the Guibo to the tranny output flange.
If they will not go together, you have not dropped the engine correctly or you need to loosen the spline gland nut
near the driveshaft center bearing.
Mr. Dun Rite: The manual says to use new bolts and aircraft style nuts. Get from dealer.
Replace your Guibo with a new OEM unit if it is over 75k miles old. Don't remove the strap (if new) until it has been
bolted to the driveshaft and tranny. If used, use 2- 6” PVC hose clamps to compress the Guibo. (Giant "WaterPump"
pliers work too).
Gearshift & “poopdeck”
While the tranny is slightly dropped, bolt the sheetmetal gearshift “poopdeck” to the rear of the tranny 2 – 10 mm
bolts and install the gear shift levers. There is a rubber bumper at the rear of the “poopdeck” that bolts up to the
transmission hump. Do not forget the molded foam insert for noise control.
Reverse Light Sensors
Secure to top of transmission while slightly dropped.
Install speedometer cable fitting. Secure with special 10 mm bolt.
Install at sliding rails flanking the transmission hump. 2 – 10mm special bolts and nuts. Leave loose. Secure rubber
tranny mount w/ 17mm bolt. Check that tranny and driveshaft look aligned. Tighten rail nuts.
Mr. Dun Rite: How do you know if things are aligned when you upside down on a creeper under the car with a greasy
Install clutch slave
Install with 2 – 10mm nuts to studs on the bellhousing. Secure hydraulic line to tab on the bellhousing. 15mm bolt.
Mr. Dun Rite: If your clutch slave is over 100k miles old, it is time to replace it.
ClutchSlave1.jpg (21453 bytes)
Using a new gasket(s) install downpipe to headers. 3 nuts onto rusty studs.
Use a die to sweeten up the stud threads. Use graphite thread compound. Secure exhaust pipe at transmission
Mr. Dun Rite: Get 3 new copper nuts from your dealer or parts monger .They do not rust.
Install at downpipe. Use gloves, do not touch the white ceramic tip. Install a new unit to simplify tuning.
Power Steering Pump
Install pump to accessory brackets. 3 – 13mm bolts. Install belt. Adjust tension and tighten adjusting bolt.
Install adjusting bolt and nut to sliding arm from timing case. 13mm. Install fan belt and adjust tension. You can use
your handy 18” ratchet bar to lever the pump / fan belt tension.
(If old E12 style)
Needs to go on before radiator is installed.
Chassis Wiring Harness
Install the wiring that feeds from the drivers side. It connects the oil pressure sensor, the alternator wiring, engine
coolant sensor and ground, it wraps around the front of the engine, distributor wire, ignition and coil wiring. It
secures to the dip stick & the distributor. Use plastic wire ties at the distributor splash plate.
Mr. Dun Rite:
Use dielectric grease at all connections.
Secure to driver side engine mount bolt.
Secure to engine. Check for condition of wire and connections. If disreputable, replace for future electrical
Mr. Dun Rite:
Use dielectric grease at all connections.
Connect the starter wires 2 spade connections and 1 - 13mm bolt.
Use dielectric grease at all connections.
Heater Supply / Return
Secure to firewall plastic hose nipples. Orient hose clamps so you can get an extra long screwdriver on them parallel
to the fire wall.
Lower Radiator Hose
The mounting of this hose is critical. The clearance at the bottom radiator to the AC Pump pulley is very tight so the
hose must be angled and positioned correctly. Further it is bear to get it onto the thermostat housing intake, further
the clamp position is important for screwdriver access, further the dealer OEM hose we got was 2” too long and had
to be cut to size. Leave hose loose until the radiator is installed.
Make sure the hose does not rub against the AC pulley.
Radiator and fan shroud E 12 OEM
Install your radiator on the factory rubber pads. Slide as far to the passenger side as possible. Check the bottom
hose for clearance at the AC pump. PC had to install a wedge under the right side of the radiator to tilt it up away
from the AC (hose grinding) pulley. Secure pass. side bracket with 2 - 10mm sheet metal bolts. Attach lower hose.
Attach temperature sensor spade fittings near lower hose. Slide plastic shroud into position, there are two tabs at
the bottom of the radiator. 2 – sheet metal screws at top..
The E 12 brass OEM radiator is easily replaced with an E28 aluminum 535 radiator that has more cooling capacity.
It mounts in the same position however the brackets are different and require some minor sheet metal cutting and
drilling. You need to use the 535 top and bottom hoses because the radiator nipples are different. The going price
seems to be around $125 for a used unit.
Install upper hose and small diameter reservoir hoses. Attach heater return manifold hose to reservoir.
You can use fuel hose for the radiator return.
Brake Booster Vacuum Hose
Reattach brake booster hose to manifold. Clamp tightly.
We both had trouble with this hose. It is stiff, un-yielding and gnarly. We had to cut it off the manifold. We got some
hose off a wreck to replace the portions that we had cut. It is designed for extreme vacuum pressures. The dealers
have trouble getting it. Sean was able to obtain some new, but it was pricey!
Grease ball joints and install. They snap into place. Connect at firewall and from bell crank to throttle.
PC now own a 533i with a cable linkage. The visceral feedback from the E 12 hard rod linkage is a joy! The cable
Injection Wiring Harness
L Jet Specific
Carefully reroute the harness from the firewall to run beneath the manifold log. The wire should all have a “memory”
and should fall into place. It helps that you left the throttle body off to gain access to the #3 & #4 injector plugs.
Check to make sure that all of the connectors can reach their plugs. Note that there are several grounding
locations. Re-plug all of the connectors. Reinstall those little square wire clips at the injectors and sensors. Install
all of the rubberized loop wire holders. Secure harness to firewall with plastic wire ties.
Wire harness installation looks to be similar. The main firewall bundle is routed differently.
Mr. Dun Rite: In order to facilitate easy cam cover removal, PC re-engineered the wiring stays to hang from the
triangular log supports and abandoned the stays at the upper bolts of the cam cover.
Secure the crankcase vent “elbow” hose to the bottom port of the throttle body. (If you are like Sean, attach small
diameter idle warming hoses at bottom of throttle body.) Reattach with 4 - 10mm nuts.
L Jet Specific
Engine must be at Cylinder 1 TDC. (Check the cam lobes at #1 Cylinder to verify.) The distributor has a #1 location
mark in the lip of the metal body. That mark will end up at approx. 3:30 when looking at the engine from the
passenger side. Insert distributor with mark at 11:00 and twist clockwise into position. The vacuum cone should
almost being pointing up. If not, twist distributor out and try 12:00. Set clamp bolt loosely.
Install the distributor cap and ignition wires.
Mr. Dun Rite,
Get a set of high performance 7mm or 8mm ignition wires. They seem to make a difference especially at lower RPM’
s. ALLBMW has a good deal on high performance wire sets.
L Jet Plumbing and Hoses
Install vacuum hoses, cold start and fuel hoses, cold start air hoses, AC air increase solenoid, etc.
This is all easy if you labeled them.
Attach fuel hoses to fuel rail. Attach hoses to charcoal canister beneath washer fluids container.
Mr. Dun Rite,
Replace all of your fuel hoses with new BMW OEM hoses. Avoid freeway engine fires. The new fuel additives are
hard on 20 year old hoses.
Air Flow Meter
Attach meter box and secure wiring harness to multi-point plug.
Add engine OIL!!!! Don’t forget this!!! Could cause BIG problems.
Final Check outs
Tie wrap all wire out of the way of moving parts.
Check and tighten ALL coolant hoses.
Install and tighten all belts.
Make sure fuel hoses are routed correctly and are tightly clamped.
RECHECK Connections, hoses, belts, etc. AGAIN!
Install freshly charged (new(DunRite!)) battery
Check the dipstick.
Leave the coil wire off. You will want to crank the engine a bit before letting it fire. This is to pump up some oil
pressure. It will let you see if you make oil pressure and not have to worry about shutting it off FAST!
If you get oil pressure(light goes out). Add the coil wire.
Mr. Dun Rite: Take a break, have a beer, chill out. Go back over the list AGAIN and make sure that you have hooked
everything back up correctly and that there are no loose wires or hoses.
Fire Der 3.5er Up !
Jump into the drivers seat and turn the key.
We were lucky, the timing was pretty close, and the FI was working fine before the swap, so the motor came to life
Set the timing. See the “Haynes” or BMW manual on this…..
Bleed the coolant via the thermostat port. Top off coolant.
dutch.jpg (67662 bytes)
Drive Der Autobahnen Muncherkin
Notice the deep surge of low RPM torque as you pull away from the stop light. Feel a continuous surge of ever
increasing power all the way to 6000 RPM. Forget those 2.8 flat spots. Forget to shift as much.
Let it idle. Listen to a deep primitive rumble emanating from the pipes.
Re- fill it with gas a lot more often.
***More to come
The followup of this FAQ will be along shortly on “tweeks” to do to get the most out of you newly installed 3.5 ltr. We
are sure we most likely have left out something in here, so let us know and we will modify it. We’re sure we
missed/omitted something you will encounter.
CLEANING EVERYTHING. We practice DunRite’s to the “t”, but we also wanted minimal downtime for the car(s). Sean
was ready to do all new gaskets, etc…. But cleaning all the parts wasn’t there for him… PC told Sean if he wanted his
continued help “YOU HAVE TO CLEAN ALL THESE PARTS!” so Sean spent three weeks (ok not that long) cleaning
parts. He is really glad he did! The car is now a pleasure to work on without getting dirty.
If you have access to a parts cleaning machine, use it! Sean ended up using a giant “rubbermaid” container and
filled it with a batch of some stuff called “oil eater”and water. Each night he dropped a piece in to soak and then the
following evening he’d clean that part. Then in with the next. Old toothbrushes, household cleaning brushes, etc. all
work well. Also LOTS OF RAGS! This is “smeg” removal at it’s finest. A lot of work, but well worth it, in hindsight.
clean_parts1.jpg (60107 bytes)
The 535 motor is a drop-in with the following notes:
- The end of the camshaft has a Motronic-only drive on it. If you plan on
using carbs, you can get a conversion nut for $60 from Metric Mechanic --
this would also necessitate using your old upper timing cover, distrib,
distrib drive gear.
- Your old carb manifolds bolt right up, as does the old thermostat housing.
Use the Bav exhaust manifolds, as the 535i ones are 60 degrees different on
the downpipes connections.
- Use the old brackets from motor mounts, A/C, PS, alternator. The mounting
holes in the block are identical.
- Auto cars did not have a pilot bearing in the back of the crankshaft. The
input shaft of the manual tranny rides in this. Make sure you install one.
- Your 4-speed, clutch, flywheel, throwout bearing, clutch slave cylinder
will bolt up fine. On the old blocks, there's an aluminum reinforcing
bracket in front of the slave cylinder. The 2 mounting holes do not exist on
the new block. I drilled & threaded the block and used it -- most folks just
leave it out and do fine that way.
- Be aware of the fuel tank return line needs if going Motronic. Other
people can give more detail on this.
- '88 head has no Mech fuel pump drive, so you'll need and electric pump and
a requlator in the trunk.
- There is no coolant return port on the Left-rear of the new block. On carb
blocks, this connects to you choke-heater coolant lines. If going with 32/36
carbs, get electric chokes @$25/carb.
- If using carbs, use your old valve cover and associated studs.
- Use the 535 oil pan. Just snip the oil-level sensor wire.
- If going Motronic, I think the big E3 brake booster is too big --others can confirm/deny.
M5 Motor Conversion
Pulling motor / install a 3.5 Liter
5 Speed Conversion