Engine Rebuilding Project

3/7/99    Today I started the disassembly process on the car.  It hasn't quite quit running but it is close.  I managed to get the intake tract and plenum off and stopped at the throttle body removal because I couldn't figure out how to disconnect the wiring to the injectors from the top of the injectors themselves..   Below are two images of the progress that day.  Only took me about 4 hours to do this.

3/8/99  I took the throttle bodies off and separated the fuel injectors from the connector rail.  That allowed me to remove the throttle bodies and injectors as one unit.  I looked down inside the head on the intake side and it is very clean.   That's GOOD!  The fuel injector pintles are also very clean which is another good sign.

3/10/99    Not a lot of progress made.  Removed coolant recovery tank and the washer tanks.  I had to remove the front bumper to get the connections to the washer tanks.  I loosened the bolts on the alternator and smog pump but was not able to free them enough to remove the belts.  I can't remove the belts which means I can't remove the fan, which means I can't remove the fan shroud and finally, I can't remove the radiator like I was trying to do.  I removed some hoses, and wiring and labeled them all.

3/1799.  More disassembly has taken place.  The following pictures can attest to that.  I've encountered my first major problem.  One of the cam chain guide bolts uses a hex head bolt and it is on the verge of stripping the head.  I wouldn't be to concerned if the bolt was going to break because I can replace it, but right now I am worried I won't be able to get the guide off.  Without removing that, I cannot proceed.  You can see the socket head in the fourth image.  The first one is the top of the cam box.  The second is the thermostat housing.  The last image is the pile of parts I am accumulating. 

3/19/99  I'm going to try a low pressure impact tool on the cam guide bolt in an effort to loosen it without stripping.  If it strips, I'll see if I can get a larger hex head driver in it or I guess I will have to drill off the head of the bolt. 

3/29/99  Finally had a little time to work on the engine again.  The current process is to remove the cam box to get to the head.  I removed the cam gear bolts from each gear after bending back the retaining clips on each bolt.  The exhaust cam gear had an additional attachment on the front of the gear held on with a 6 mm hex cap bolt.  I don't know what it was for.  After removing the bolts the gears were free to removed, which I did.  I used tie wraps to secure the chain to the gears and the gears to the cam box to keep tension in the chain to keep it on the crankshaft.   The gears could not be removed because I did not have enough clearance between the gears, cam box, and ends of the cams.  Next, I loosened the cam cap nuts and started backing them off equally to allow the tension in the valve springs to relax.  After the valves had reseated, I removed the nuts, caps, and the cams.  There are not any cam bearings, the caps and the cam box are machined to act as the bearing surfaces.   Both are aluminum so be careful if you remove them.  I put rubber sleeves on the studs before removing the cams to prevent scoring the journals.  Both cams were removed in this fashion.  There is one important note from this process.  At the rear of the cam box there is an aluminum cover that is held on with 6 10 mm bolts.   This cover prevented my putting a socket on the rear cap nuts and the removal of the caps.  I removed the two the top bolts holding the cover in place and loosened the other 4 enough to push the cover back.  The 4 bolts I loosened are difficult to get to with an open ended wrench.  I decided not to remove them because the clearance between the rear of the cam box and the firewall is so tight, I might not have been able to get them back in.  The last image shows this cover.

4/1/99  Pulled the head off last night and the news isn't good.  The #6 cylinder wall is scratched.  I can feel the groves with my finger which means that is how the oil is getting into the combustion chamber.  I suspect a broken ring for some reason.  I removed the 14 head bolts with a 12 mm 12-point socket.  These are put on with lots of torque so it wasn't easy to get them off.  There are two 5 mm Allen head bolts on the front of the head that holds it to the block.  Once all these were removed, the head was free.  As I lifted it, I could hear coolant running down into the cylinders and into my drain pan.  Some of the images show bits of water in the cylinders.  I dried them as quickly as I could, but I guess it doesn't really matter since the bottom end had to be rebuilt anyway.  Images 20 & 21 show the head after the bolts have been removed and it's ready to be lifted off.  Image 22 is the valve train components without the cams.  I wrapped them up pretty good for protection and I didn't want to unwrap them.  Images 23 & 24 are the block with the head removed.  #25 is the #6 cylinder and you can make out the scratches.   Image 26 is poor quality because of focal length, but you can definitely see the scratches in the cylinder walls.  #27 is #6's valves and you can see the burnt oil build up on both valves.  The last image is the head as it was sitting on the floor.  The rear of the head is up.  Notice all the exhaust valves (right side) are about the same color, but there is carbon build up.  The engine must be running a tad rich.

4/8/99  The block is ready to be removed with the exception of the transmission.   I began the process of removing the transmission last night and, of course, it isn't going to be easy.  I first removed the 13 mm bolts holding the clutch slaver cylinder on.  There is a rear cross member with 4 17 mm bolts holding it to the body.  Those all have rust on them, so it should prove interesting.   The exhaust system runs under the tail shaft of the transmission which will present clearance and maneuvering problems to get the tranny out.  4 large bolts hold the driveshaft onto the front u-joint.  My '93 Formula uses 7/16" nuts on the u-joint.  These look like 17 or 19 mm bolts.  The driveshaft flange is about12-14 mm thick with a rubber vibration damper.  The bolts holding the tranny to the block are Torx bolts so special sockets are required.  I discovered after removing the engine and tranny that there is transmission to engine bolt on the drivers side behind the starter hole that is not on the bellhousing flange.  This bolt cannot be seen and is probably difficult to feel, but it is there.   I cleared the engine bay of all the electronics, unbolted the hydraulic pump and the AC compressor and removed the air pump.  The images below show that the block is ready to be pulled.  Oh what fun!

* Note:  I had several e-mail discussions with Jim Comforti who has agreed to fix me up with one of his custom EPROMs with the correct ECM program for this car. 

4/19/99  I managed to get the block and tranny out of the car last week.  I have the engine on a stand and have started removing a few parts to get it ready for the machine shop.  The top of the #6 piston is melted for some reason.  The compression ring is obviously damaged as a result.  Looks like boring and new pistons are in order.  That ought to be a pretty penny!  To get the engine out required the removal of the passenger side motor mount to that it could clear the headers.   Not much holds the tranny in the car except the rear mount, driveshaft bolts, and the shifter linkages.  The shifter linkages were the hardest to get free, especially the upper bar.  There is a clip that holds it to the transmission housing that is not easy to see.  When I finally was able to get a good view of it, I just rotated it up and pulled it out sideways.  This freed the transmission and I was able to lift it out with the engine.  As I lifted engine and tranny, I had to turn the unit towards the passenger side to gain additional clearance.  I did not remove the front pulley or harmonic balancer.  I left the hydraulic pump and AC compressor connected to the hard lines.  I just pulled them over and out of the way to remove the engine.

I have removed the clutch pressure plate, friction disk, and flywheel.  The pressure plate is in good shape but the friction disk appears worn.  I looked at the flywheel and it is okay.  The pressure plate is held on with 6 12 mm bolts and isn't torqued down much.  The flywheel bolts are 19 mm and are probably torqued to about 30-40 ft lbs.  With the flywheel off, access to the rear main oil seal can be accessed.  It is a one piece unit that bolts to the rear of the block. 

4/21/99  I have the engine almost ready to go to the machine shop.  I need to get the ring ridge removed from each cylinder and then I can remove the pistons.  The machine shop will check all the dimensions of the cylinders, crank main and rod journals and the rod bearings for clearance.  It has been recommended that I replace the bottom end bearings since I have the bottom end opened up.   The first two images are of the clutch pressure plate, friction disk, and flywheel.   Sure is a small clutch.  The third image is the very light 5-speed transmission.  I picked up the unit and it weighs about 80 lbs./36 kg.  The fourth image is a rather dark picture of the engine hanging on the stand.

These next three show the front and side of the engine before I finished removing the last of the bolt on stuff.  The third image is the crank pulley hub, harmonic balancer with the crank triggers for the ignition.  The bolts sitting next to the pulley are the bolts that hold this on.  They are the same size and length as the head bolts and probably torqued to the same value as the head bolts.  They were very hard to removed.

This image is the inside of the oil pan.  The pan acts as a structural member for the accessories!  There are two bolt holes and and a brace on the left front of the oil pan which isn't visible.  There is a tube float thingy bolted to the bottom of the pan that needed to be removed to get the pan off.  I think it is an oil level sensor, but I'm not sure.

These next two are of the bottom of the engine showing the crankshaft, main caps and the connecting rods.  These are some really big caps and connecting rods!  The bolts are about 7/16" at least, which is about an 11 mm bolt.  Big.

These next two images show the cam chain and guide assemblies.  Interesting set-up BMW came up with.  The oil pump is also chain driven off of the crankshaft.  S38 engine owners better hope that chain never breaks.  It would be very ugly inside if that happened.  The images show the block upside down. 

The last two images are of the #6 cylinder.  They show the damaged piston fairly well.  I'm not a wizard with the macro feature on the digital camera but they are not too bad.  When I get the piston out, I'll take some more.  I have no idea what actually happened here, but I think it has to do with the ECM program.  To get the car to pass US emissions specs(previous owner), a non-dealer repair shop programmed the ECM with a different program.  It might have made the engine run too lean.  This looks like the result of detonation to me.  I might be wrong, though.  Opinions?  I believe there was a post on the M5 Message Board that discussed an Australian car owner that was sold the wrong JimC chip.  He didn't get an expected power increase and I would be very concerned that something like what happened to my motor might happen to another M5 using the wrong program.  Chip upgraders beware!   Make damn sure you get the right program.

4/22/99  Last night the final engine disassembly took place.  I pulled all the pistons out.  Each rod and cap have a matching number on it to keep them straight.  The numbers face the passenger side of the engine to keep the rod oriented on the journal correctly.  The #6 piston looks like a victim of a lot of detonation.   Below are the several images of it. 

5/5/99  Nothing new to report.  The block is still at the engine shop because I am waiting on the pistons and rings.  I had a hard time getting the parts because every place I called for a quote had to either contact Germany or call someone else.   That someone else ended up being Bekkers.   I was finally able to get most of my parts from Bekkers, but I also ordered some from All BMW Parts.  I ordered pistons, rings, main bearings, rod bearings, head gasket kit, lower gasket kit, clutch disk, pressure plate, throw out bearing, pilot bearing, head bolts, and a vacuum check valve.   I'm hoping to get the parts next week and hopefully the block back by 5/14/99.   Then I'll start putting this puzzle back together.

5/12/99 I have uncovered some information on the pistons and bore for the car.   Visit here. 

5/20/99  Bekkers shipped the pistons, rings, and gaskets on 5/18/99.  With luck I should have them this Friday or early next week.   After that, the machine shop can do their magic.  Sorry to keep everyone waiting on the outcome of this project.  I did not expect it to take three weeks to get parts.  Sheesh!

6/1/99  The block should be ready today. I'm still lacking some bearings from All BMW Parts.  When they ordered the bearings for the rods and mains, they ordered sets from the parts book.  However, a "set" of rod bearings includes 6 half shells not the 12 required for the engine.  A "set" of mains includes 6 half shells, not the 14 required.  I was disappointed that no on with any knowledge of this checked it at ABP before shipping.   They were supposed to be ordered the day I called.  It never fails.  Small things like this will always hamper a project like this.  Bummer!

6/15/99  Still waiting on the bearings from All BMW Parts.  This is taking %#&*%@ forever.

7/9/99  I should have all the bearings either tomorrow or Monday to get started on this blasted project.  A note to anyone out there going to buy parts for their BMW.  DO NOT BUY THEM FROM All BMW Parts!!!  They messed up my bearing order twice.  This was after I explained to them that they are ordering only half of what I am asking for.  They won't get my business again.  I called Bekkers.   They seem to know what they are doing.

7/15/99  I FINALLY got all of the part I need for the project.  So far, I have put the crank, pistons, and the oil pump in and on the block.  I torqued everything down to the recommended specs.  I was concerned which way to put the main caps on.  Since they can go two ways, the notch in the bearings can either be on the same side as the notch on the block bearing or on the opposite side.  BMW made the main caps in such a way that they only go on one way, so you can't get them backward.  It's not that they designed them that way, it's just how the machinist grinds the ends of the cap.  Since these engines are hand built, the caps won't fit on any other journal.  This image shows that the cap won't fit in backwards.

These images show the crank in place with assembly lube on the bearings and journals.

7/21/99 After putting in the crank, pistons, oil pump, cam chain, guides, etc., I noticed a threaded hole in the block near the water pump.  I started looking at my old images of the disassembly process and noticed that in image 43, the was a plug in that hole.  It turns out that this is an oil galley plug that needs to be removed when the block is cleaned.  The machine shop did just that, only they screwed me by not putting it back in and then loosing the plug.  Long story short, the plug is NO LONGER AVAILABLE through BMW or anyone else.  I was told that BMW uses Witworth(sp?) thread pitch on their bolts, studs, nuts.  The rest of the world, (except Jaguar) uses standard metric.  The Witworth has a slightly different pitch.   This is a very uncommon thread and no one really carries it.  Another word to the wise, DON'T loose, break, or strip your fasteners.  You might have problems finding them.  In addition, I notices a few instances were the standard metric thread is used so BMW may use both or may be converting to the standard metric.  However, the up side on this is the plug utilizes the standard metric thread.   I replaced all of the pan bolts with new stainless M6x1.0 bolts and lock washers.  Next warning, if you live in Austin Texas, don't take your engine work to K.O. Machine.  That is the shop that did my block and I am not happy with their turn around time and loosing my plugs.

This image shows what the oil pump looks like taken apart.   Good thing I looked inside because there was some gook inside that I cleaned out and then put assembly lube on everything.

Yesterday, I put the cam chain cover on.  I also put new seals in the cam chain cover and the rear main and installed them.  I also put the oil pan back on along with the oil level sender.  I used a thin coat of Hylomar on the cam chain cover because I do not want it to leak since it is so hard to get to.   I put a little bit of Hylomar on the seam between the cam chain cover and the block and the rear seal housing and the block.  The oil pan gasket is cork so I didn't use any sealers.  The oil pan flange is machined aluminum so it is pretty flat.  I'm not worried about it leaking because there is like 30 bolts holding it on.  Next up is the motor mounts, flywheel, clutch disk, and pressure plate.  After that, I drain and fill the tranny and bolt it to the block.  After that, put the engine and tranny back into the car.  :-)  Making progress!  This is the oil pump and the   rear main cap and flywheel mounting flange.

7/26/99  I took the weekend off to spend some time with my daughter before school so no progress.  However, today I put the accessory brackets on both sides, motor mounts, and the harmonic balancer.  I had to do a little investigative work first because I managed to get the bolts mixed up for the brackets and had to mess with that.  I was only able to torque the harmonic balancer to 75 ft. lbs. because my torque wrench didn't go up that high.  A friend is going lend me his so I crank it up to the required 92 ft. lbs.!  Below are a few images I have.  

8/2/99  Well, things are starting to move a little bit here.   I got behind in my updates because of computer issues.  These images below are the engine on it's last days on the stand.  I have the covers and engine mounts on along with the only sensor.  You can see the oil level sensor along with it's proper routing.  I had to get a friend help me torque the harmonic balancer bolts to the recommended 92 ft. lbs.  That was tough to do.

8/5/99 Spent a little more time on it today to install the flywheel, clutch disk, and pressure plate so I could put the tranny on.  I drained the transmission and put new Redline manual transmission oil in it.  The transmission only takes 1.5 quarts.  I think that's about a liter and a half, or close to it.   The first image shows how long the engine and transmission actually is.  I didn't have much trouble putting the transmission on even though I didn't have a clutch pilot tool to align the disk.  I eyeballed the disk as best I could then I inserted the transmission and which lined up the disk and the shaft didn't have any problems entering the pilot bearing.  I then removed the transmission and tightened up the pressure plate bolts to the recommended spec.  After that, I just had to re-insert the transmission.  This time it was a little more difficult to get it lined up.   Once I did and it was about 0.5 inches away from the block, I just inserted all the bolts and slowly tightened them up to pull the tranny up to the block and then torqued them down.  I then inserted a large screw driver into the slave cylinder hole and pushed on the clutch lever.  That released any stress on the disk and allowed it to center and line up correctly.

8/7/99  After about and 2 hours of work, my roommate and I managed to get the engine and transmission back into the car.  Not much to say about this, but we got lucky and managed to get it on the first time in.  We made 5 attempts total to get the lift chain on the right link to get the correct pitch on the transmission so it would go into the hole, clear the sway bar, and not allow the oil pan to hit the front of the engine bay.  Once we got it down, I crawled underneath and inserted the transmission tail shaft pin into the driveshaft.  This is key to getting the engine in easily.  Once that was done I just pulled the tranny over towards the drivers side and then went back up to to lower the diver's side engine mount to the bolt.   Once that was in close, it only took a few jerks to get it where we wanted it and then down.  After that, the other side went down nicely.  We stepped back and she was in.  I then proceeded to tighten the 6 driveshaft bolts and put the transmission mount on.  I reconnected the three wires going to the reverse switch on the passenger side.  After that, I connected the slave cylinder which took a lot of strength to compress the piston, and attach the bolts while laying at an odd angle.   The images below show the engine in the bay and a close up shot of the #1 piston.   You can see the writing on the top that identifies the diameter, the cylinder wall clearance, compression ratio and the direction to the front of the engine.  If you look close, you can see that the piston is higher than the block.  The head gasket provides the necessary clearance between the piston and the head.  Makes your appreciate the valve reliefs cut into the piston.

8/7/99  These images show the progress I made after putting the engine in.  The accessories went on pretty smoothly, which was very much appreciated.  I needed a break.  Everything was just falling into place, so to speak.  I was very happy with the progress

8/8/99  Today I continued with installing accessories.   I had to remove the air pump because I had the hoses routed wrong.  I came across a vacuum valve with large hoses on it and wondered where it went.  When I started looking at it, I realized where it went, so the air pump had to come out.   Glad I figured it out now.  I completed some wiring on the diver's side to the alternator and a few other connectors.  I have one connector that has a mounting bracket attached to it but I'm not certain where it actually mounts.  I have one place I think it could go, but I'll just have to see.

Here it is!  The head is now on the block!   You can see the headers in the second shot.  Installing this head was a pain in the _ss!  I was getting killed on the water tube in the back.  To make this process easier, don't tighten the tube until after the head is on.  I put some cuts in the head gasket around the guide holes for the water.  I don't think it will be a problem since the guide holes have a raised lip that goes into the block and that the hole in the gasket that surrounds the guide hole is much larger than the guide.  I think I'm safe.  I also bent the head gasket a little at the front where the cam chain is.   It's not an area near a cylinder so it should be okay too.  Not much I can do about it now.

8/14/99 Progress is moving along.  I'm stuck waiting on parts again.  When I removed the cam box a few months ago, I partially stripped the heads on at least two bolts and completed stripped another.  I ended up drilling the head of that one off.  Anyway, I had to order them from BMW.  These bolts are the hex socket cap bolts that hold the cam box to the head.  They are an unusual size, 7 mm x 1.00 mm pitch 40 mm long.  An M7 is a Japanese size, not standard metric which is 6, 8, 10, ...  I've put the exhaust heat shield and water tube on the exhaust side.  O-rings are used on the water tube for sealing.  I also started the rewiring on the drivers side of the engine.  Since I took the trouble of labeling all the connections, it's been pretty easy to put them back in the right place.

Below are pictures of the head with the cam box in place.  I don't have a gasket for the cam box to head interface.  I'm not sure if it needs one, I'll have to check on that.  I think that it may just use RTV sealant.  Because of that, the cam box is just resting on the head and is not bolted down.  In addition, I don't have the bolts I need to torque it down anyway.     I received some answers from Lee at Black Forest and John Robinson on the gasket issue.   There is not a gasket between the cam box and head.  I used a thick layer of Hylomar to seal it.  Worked pretty well, I think.  I have an image of it below.

	Cam box in place and ready to bolt down.  Wire is to hold the cam caps in place.
	This one is before I put the wiring in place on the drivers side.
	After the wiring has been put into place
	The cam box before installation.
	Close up of the head.  Notice the o-rings around the spark plug holes.
	Nearly ready to torque down.
	This has been my home during my free time.  It's hard to believe this was a big hole in  month ago.
	Both cams in and the head coated with Hylomar between the head and cam box.  Thick and smooth coating.  Not sure why there isn't a gasket for this interface.
	Another view of it before I put the cam box on.
	Intake cam ready to go back in.  It's covered with assembly lube.
	Close up view of an intake came journal surface.  Looks pretty good.
	Valve lifters all lined up and ready to be reinstalled.  I numbered them all so they will go back into the hole they came out of.
	Here's; what they look like back in the hole of the cam box.   They are a slip fit so don't force them or get them in crooked.  I coated them with assembly lube.
	Intake came in and torqued down.
	Another view of the intake came after installation.
	The front of the engine looking at the wiring harness, cam covers and water pump.  This is what it looks like behind the front water tube.
	Valve train is installed, gears, top cam chain guide, and the chain tensioner.
	Here's how you line up the cams.  There are two notches on the cam.  One notch lines up with the grove on the bearing cap, the other grove points at the other cam.  Make sure the crank is on the TDC mark before installing the cam gears and chain.
	Another view of the marks.
	This the #6 fuel injector after being cleaned and flow tested.   It and all the rest passed with flying colors.  Less than 5% variation between them all.
	Throttle bodies are installed long with most of the wiring harness.
	Smog pump, AC compressor, wiring and the gold looking round thing is the cam chain tensioner vibration dampner.
	Thermostat housing and front water tube crossover.
	Hmmmm, wonder where this goes.  I did manage to find out where this connect.  The other end goes to the smog pump vacuum valve and this end goes to a connection on the bottom rear of the intake plenum.  I had to go look at Rick's M5 to trace the line.  His was disconnected.  I reconnected it for him while I was there.  It's a loose friction fit, so it's not surprising his was off.   I'll bet most M5's on the road have this line disconnected and don't even know it.
	Radiator, oil lines, and vacuum lines in place.  I'll replace new belts, spark plugs, and the intake plenum, then fill with fluids and it should goo to go.
	This side is nearly done.

10/20/99 This update is not a cheery one.   I put the engine and car completely back together and started it up.  The engine didn't fire the first couple of times I tried because I had two connectors on the front of the engine switched.  These are the only two on the engine I found that have the same connector.  I managed to mix them up,... go figure.  Anyway, the engine ran but made a lot of noise from the valve train.  I suspected the cam chain tensioner was not installed properly so I removed it and check it.  It was fine and the tension on the chain was correct.  I tried several different ideas and found nothing.  I transported the car to Phoenix Motor Works in Austin and asked them to look at it.  They checked cam to crank alignment and found it to be correct.   They removed the head and discovered that each of the exhaust valves is hitting the top of the the piston.  They suspect that  I have the wrong pistons, ones that are too tall.  I contacted Bekkers and Mahle (piston maker) and they confirmed with me that there are only three pistons made for the car other than stock.  Each one varies by bore diameter.  The overbore sizes available are 94.605, 94.755, 94.955 mm.   This is a clean up piston, 0.02" overbore, and 0.04" overbore.   Mahle lists them as 94.6, 94.8, and 95 mm.  After learning that last Friday, I am no longer convinced that I have the wrong piston, but that the exhaust cam was not aligned properly.  I am going to work two paths to resolve this.  I will remove one piston from the car to compare with and old one.  I will contact BMW Gmbh to obtain information on exactly how to line up a Euro spec M5 engine.  I will have the second part done tomorrow and the first part done next week. 

11/16/99 I finally removed the #1 piston from the car about two weeks ago and took it to work to measure.  To do this, I had to remove the oil pan and oil pump.  Not too hard if the head is off the car.  I was able to lift the engine up enough to get the pan off.  I measured the new piston and compared it to the old one I have left.  The overall height difference between the wrist pin centerline and the top of the piston was different.  The newer piston is 0.015 inches SHORTER than the old one.  This leads me to believe that the pistons are not the problem and that the original problem was the cam timing on the exhaust side.   I was concerned about this from the beginning because only one side was hitting not both the exhaust and intake.  In my mind, if the pistons were too tall, all the valves would hit. 

I returned to Phoenix with both pistons, a digital dial gauge my data and a new determination.  Everyone I spoke to at the shop could offer no new ideas as to the actual problem since now I showed them there was not any appreciable increase in piston height.  The shop owner and head mechanic were back pedaling the whole time.  After a lengthy conversation, they admitted that based on the evidence I provided, it appeared that they did not need to remove the head and that I may have paid for something I didn't neet.  I agreed.  The suggested that I return the car to them with the necessary parts required to continue the investigation at no charge to me.  That's where it stands now.

The car is back at Phoenix and Quirt began working on it this afternoon.  He said that he will have something to tell me tomorrow afternoon.  Right now, I told the shop owner that he owes me 10 hours in labor and nearly $700 in gaskets that I had to order to reinstall the head and the oil pan.  We'll see what happens next.

11/30/99  Waiting on parts for the car.  BMW at Gmbh has reported that there are some problems encountered with the 92 cam chain system.  They recommened replacing the gears, chain and tensioner with parts from a Euro M3 3.2L.  The parts are on order and should be here this week.   If they arrive, the work on the car will begin next week with possible completion then as well.  Phoenix has comitted to returning the car to me in tip top shape.   They have admitted to partial fault to the head removal.  Isn't it interesting how BMW repair shops never seem to be at fault with anything they do?  Anyway, they have reduced the cost of the repair.  I get to buy the parts from someone else other than them which is saving about $325.  Hopefully soon I will have something more than a money pit.

12/23/99  I got the car back today from Phoenix.  I'm very worried about the car since the engine is new.  I drove the car very gently around town.  It was great to have the car back, but the front end "shimmy" needs to be fixed.  This is the famous 5 series shimmy.   That will have to be next along with some new tires.

Note:  For some reason, I never made additional updates on the progress of the engine after I got he car back.  So, here's an update from May 5, 2000.

1/10/00  I ordered new 7 series front bushings to correct the shimmy.  I removed the passenger side thrust arm without too much difficulty.  The 22 mm bolts are VERY tight!  I had to use my leg with the wrench to break the nut loose.  After some wrenching and twisting everything was free except for the ball joint.  A couple of raps on the side of the spindle base jarred it loose.  I took the arm and one bushing to the machine shop.  I was only able to get the passenger side off.  The driver's side ball joint is so tight I cannot get it free.  The machine shop pressed in the bushing without any trouble.  The ball joint was still good.  I reinstalled it in about 30 minutes.

1/14/00 I have tried and tried to get the drivers side ball joint loose without success.  It is just so tight and will not come loose.  I beat the hell out of the side of the ball joint.  I finally resorted to beating on the end of the ball joint knowing that it was ruining it.  I ordered and new thrust arm from Carparts.com.  The dealer wanted $228, Bekkers wanted $148 and CarParts listed the part for $112.  It should be here by the end of the week.  I also ordered some new tires for the front.   Yokohama AVS Intermediates.  Tire Rack sells them for $121.  They should be here early next week.

1/17/00 I cannot get the drivers side thrust arm off so I am going to have to take it to a friend who owns a repair shop.   He said he would swap the new thrust arm for the old one. 

1/18/00 I got the car back this afternoon.   New thrust arm and all.  It pulls to the right a little so I will get an alignment after I get the tires on.  With both bushings replaced and everything bolted back on, the front end feels tight again.  No more wiggles in the corners.   :-)

1/24/00  Okay, new bushings, new drivers side thrust arm, alignment, and tires make the car ride and handle much better.   Still not out of the woods yet on fixing stuff.  I'm not real crazy about the clutch engagement so I'm probably going to have to look at that.  I will bleed the master and slave cylinder first.  If that doesn't get it, I will replace the slave cylinder.  It's the most inexpensive part and the easiest to get to.  If that doesn't cure it, then I will change the master cylinder.  CarParts.com lists the slave at $54 and the master at $112.  Almost time for another oil change too.  The oil has looked good when I change it.  This weekend I pulled the spark plugs out to see how the car is running.   Ground electrode was light gray, not light brown as it should be.  I see some carbon buildup around the ring so the car is running a little rich.  I still think I need to change the O2 sensor.  It's the same one that was in the car when it was burning oil.  I'm sure that wasn't good for it.  CarParts lists them for about $79 and I can buy it locally for $116. 

May 5, 2000  The final results of the problems with the valve and piston problems was that the cam timing on the exhaust side was off.... slightly.  I was in contact with and engineer in Germany about the problems and he reported that they have seen similar problems with M5 and M3 European engines.  Apparently, the problem arises after the gears, chain, and tensioner are removed.  They suspect that the chain is stretched and the tensioner was not working correctly.  They suggested I replace all of them, which I did.  Bekkers to the rescue again.  This solved the problem and I had the valves readjusted about a month ago just to be sure.  The car runs pretty strong as a result, but still suffers from a part throttle surge and a 1st gear stumble.  I know all M5 engines have an off idle stumble, but this one occurs when running at speeds less than 3k rpm.  At that speed, I'll stomp the throttle and it falls on its face, then takes off a half a second later, stumbles again, takes off, yada, yada yada...  That's what I am working on now to get corrected.  See below, May 12th comment.

May 12, 2000  I've been working with Lee at BlackForest to find and correct the stumble and surge problem.  I think it is related to the DME program, fuel and spark mapping, but I'm not certain.  Lee wants to make sure all the sensor are working correctly first.  When I have been able to drop the car off, he has been checking some things.  So far, the O2 sensor has been replaced -- no change.  Lee has ordered a WOT sensor for installation.  It makes sure the engine runs rich at high RPM, which is a good thing.  It it runs lean at the top, I might smoke another piston.  My plan is as follows.  I want to get with Lee and his Modec to check the DME program and ensure it is the correct one for the car.  If it is, fine.  It it isn't, fine.  Either way, I would like to try a program sent to me by Jim Conforti.  Jim supposedly sent me the right program for the car.  I'll verify this, and try it.  Hopefully, it will help.  If it does, I'd like to try a custom program from JimC that Steve Castle is running in his 3.8 liter M5.  I want to see how that one performs in comparison.  However, I can't do that unless I know the car is running right in stock form.  All of this will be checked on a dyno and then using the Federally calibrated "dyno butt."  Mark D'Sylva recently sent me a message with some additional things to check on the stumble surging issue.  He requested I check these things before spending any more money.  I will do that and hope it solves the problem.  More details to follow.

July 6, 2000  I have not been able to get the car back to Black Forest so far.  Good thing I have two cars.  :-)  The M5 has been down for about 3 weeks while I repair the AC system.  New compressor, low pressure hose, dryer, low pressure switch and a new auxiliary cooling fan.  I chose a universal 17" fan from Perma-Cool instead of the $425 BMW fan.  I bought the Perma-Cool from Summit Racing for $88.  A few bolts, nuts, washers, and some creativity allowed me to mount the fan using the factory mounting brackets and keep the fan off of the cooling fins so no abrasion or fin damage.  I'll try and get a picture up soon.  I lost my digital camera so now I'm back to developing 35 mm film and scanning the images.  Oh joy.

I miss driving the car but I need to get it back to Black Forest for Lee to continue his investigation.

July 11, 2000  I picked up the car last night after having the AC serviced.  I converted the old R12 system over to R134a.  To do so, I installed a new compressor, low pressure line, dryer, and low pressure switch.  Not too much trouble except for all of the stuff that I had to take off to get to the parts I needed to replace.  I also replaced the auxiliary fan.  A new BMW fan is ~$425.  I didn't want to pay that much when you can get standard electric fans for about $100 almost anywhere.  I ordered a Perma-Cool 17" fan and installed it.  It fit pretty well, but I had to make some "home-made" mounting brackets.  It came out pretty well.  Haven't had a chance to get the engine really hot by sitting in traffic or anything, but I'm sure the time will come.

October 28, 2000  I just got the car back from the body shop.  Last month I took a hit from a large Dodge truck.  The body shop finished with the car and I had to pick it up in the rain.  Not too good for inspecting body work and paint.  But, I can check later and go back and get anything corrected.  So far, I have not found anything wrong with the repair.  I did not like a few other things, so I WILL NOT be going back.  The battery died and I had to go buy a new one.  The same thing happened years ago when my Formula was in for some repair from a deer strike.  I find it hard to believe this was a coincidence.  On top of that, I was kidding around with the shop buy and he admitted that batteries die in the shop, more than you would think.  It stands to reason that something they are doing is killing the batteries.  I can understand batteries that croak from being in an accident, but mine is under the back seat and the very minor damage was done to the trunk lid and tail light.  Anyway, I won't bore everyone with the rest of the details, but like I said, I won't go back.

November 2000  I had the rear sub-frame bushings replaced this month.  An annoying thumping noise from the rear finally led to this repair.  I had the car checked twice before because of the thumping and Lee could not find the problem.  Even at the last, from the outside the bushings look fine.  But, they were bad.  Once replaced, the rear end plants itself much better.  I also noticed a little free play in the steering and the front end is pulling to the right a little.  It makes tire trammeling a little more of a problem.  I will start looking for some worn front suspension parts

March 5, 2001  Wow, it's been a long time since I updated the page.  Currently, I am replacing some broken and some long time failed parts.  First off, a VERY annoying rattle on the driver's side front wheel.  I could hear it with the window down when driving near a curb, row of cars, or something to reflect the sound.  I have looked several times but were not able to figure out what it was.  I figured it was something with the brakes or suspension.  So I removed the wheel and set it aside.  It turns out the wheel cover was missing a bolt and was rattling.  It's fixed.  I also replaced the o-rings used with the water coupling behind the front bumper.  The lines feed the headlight washers.  These o-rings seem to leak much to easily.  I am also going to replace the washer pump because the pressure output is low.  Also, I am replacing the inner and outer tie rods and the toe adjusters.  The adjusters won't turn anymore so I can get the alignment completed.  Once that is done, I will check steering free play.  While under the car, I decided to inspect the vacuum hoses under the intake manifold to see if I have an intake leak that would explain the stumble when you stomp the throttle.  I found one hose with a loose clamp.  It was about 3/8" so hopefully that will help.  A test drive after the alignment will check that.  :-)

July 15, 2001  Purchased and installed a new crank position sensor.  The clearance between the sensor and the crank hub is adjustable.  My manual does not indicate the correct clearance, so I called Lee at BlackForest.  He didn't know either, but suggested that I use 1-1.5 mm as a start.  I dug out the feeler gauges and set the clearance for 1.5 mm.  After starting the engine and running it, it ran noticable smoother, especially under acceleration.  The mysterious stumble is still there, but much less pronounced.

I spent considerable amount of time researching this on the E34 M5 message board and on Bimmer.org.  I have come to the conclusion that all M5's have this stumble to some degree or another.  Some engines just seem more pronounced than others.  I came across 13 owners complaining about this same problem.  Where this might just be a characteristic of the car, I am not satisfied.  I will continue to work and try an eliminate it as much as possible.  I have repeatedly asked my girlfriend about the stumble and she says she doesn't notice it.  I guess my ass is more sensitive or I am just too anal about it.  I'm sure it is the later.  In any case, I will be checking the idle vacuum soon.  I will make sure the intake vacuum matches between throttle bodies.  I need to purchase two more vacuum gauges to have all 6 that I need.  More on this to follow.  

August 3, 2001  The ///M is at BlackForest this week getting some new differential mounts put in.  One was replaced last November, but it has been worn out because the front one was not changed and has since headed south.  Because the front one was worn excessively, I am having it replaced along with the rear one.  With both of them being new, they should last another 10 years.  I am beginning to think the rear suspension is not strong enough to handle the power this car puts out.  For those ///M owners out there reading this or potential owners... this car never ceases to amaze me.  What a freaking automobile this is.  I will miss it when I finally sell it.

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