What I do when not riding (Mechanical Content)
 

As some of you know I am a mechanic by trade and as a hobby I like to buy broken cars, fix, drive for awhile, sell and repeat. This is one of my latest projects, a 2002 BMW M-Z3 with a lower end engine knock, these engines (S54) are known for having rod bearing issues. When I first got this thing I pulled the engine apart and inspected. Once apart I found the #3 rod bearing spun, but the crank was found to be in great shape and the rod looked not half bad. When a rod bearing spins it will actually cause the big end of the rod to oval, increasing the veritcal (with the small end pointing up) diameter while decreasing the horizontal diameter. If the big end is not resized or made round again the new bearing will surely fail. So with this in mind I did my best to measure the horizontal diameter and compare it to one of the other rods. This is a particularly difficult task as the rods are still installed in the engine which is still installed in the car. Not to mention the rods are split at the big end by the "fracture" method meaning there is not a straight line seperating the rod from the cap. With using a simple dial caliper I measured the failed #3 and compared it to the good #4, the difference as best I could determine was less than .001." Keep in mind this is a not very accurate method of determination, but I decided to install new bearings and see what happens as the new bearings only cost me $150.

The plan was to thoroughly torture test the engine and then before I went to sell it I would I pull the pan back off and check the bearing condition. This lasted for 1500 miles before the engine started to knock again. At this point I decided to do it properly. This includes a rebuild consisting of all bearings, rings and gaskets along with another set of rods and lastly the necessary machine work to make the engine as good as new. I decided to document the engine rebuild for the future owner. I thought being gearheads this project would be of interest to yall here. The engine is running as of yesterday and I am starting the arduous BMW recommended 1200 mile breakin consisting of 1200 miles below 5500rpm and 109mph.

To start off here is the engine removal and tear down to long block status.

Failed #3 Bearing

http://img.photobucket.com/albums/v8...ringRound2.jpg


For BMW engines I like to remove the engine and transmission with the front suspension as unit. In doing so the exhaust, driveshaft, fan, air intake and wiring is removed. Here is the engine just before lowering.

http://img.photobucket.com/albums/v8...y/Removal2.jpg

http://img.photobucket.com/albums/v8...y/Removal3.jpg


Dropping the engine is made quite simple with the use of a lift and a table, our table has wheels to maneuver and can be raised and lowered.

http://img.photobucket.com/albums/v8...EngineOut1.jpg

http://img.photobucket.com/albums/v8...EngineOut3.jpg

http://img.photobucket.com/albums/v8...EngineOut4.jpg

http://img.photobucket.com/albums/v8...EngineOut6.jpg

Next the engine accessories are removed to allow the long block to be removed from the subframe and installed on the engine stand.

Here you can see the exhaust manifolds are gone along with some of the wiring and coils

http://img.photobucket.com/albums/v8...ey/ExhOff2.jpg

http://img.photobucket.com/albums/v8...ey/ExhOff1.jpg


Next, the intake, throttle bodies and electronics are gone.

http://img.photobucket.com/albums/v8...ney/TBsoff.jpg

http://img.photobucket.com/albums/v8...ey/TBsoff2.jpg

http://img.photobucket.com/albums/v8...ey/TBsOff3.jpg


I had to install the suspension back into the car to be able to move it, so while pressed for time I had to ditch the engine off the suspension and get that stuffed back in the car. Future resting place for the engine until I can get it on the engine stand.

http://img.photobucket.com/albums/v8...LongBlock1.jpg


And finally the empty suspension getting ready to be uploaded back into the car.

http://img.photobucket.com/albums/v8...ySubframe3.jpg

Wow, that's huge. I am and always will be a gear head, even though I am stuck wearing a tie most of the time, I still like wrenching. One question, why did they have a tendency to spin bearings? My biggest job in many years was in may this year, a montronic sleeve on my 530i. It was the first big maintenance job on this car, not bad for 220,000 miles. But it was not fun using jack stands. I have never owned a car that I enjoy driving as much as this car, that does everything pretty good.

Thanks for sharing!
Lane

Wasn't there some TSBs or recalls for some 2001-2002 S54 engines with the end result being explosive disassembly? Rod bearings, oil supply or something. I have pics of this phenomenon, might take a while to find them.

Yes, the early S54's (and really all years) are affected by potential bearing failure. The original cause was blamed on faulty bearings, but I have seen newer engines with them spun too. This was a severe enough problem that BMW had two service actions for replacement, but the Z3's were to be exempt due to their slightly lower hp rating and lower RPM redline, but clearly that didn't stop mine from spinning, haha. I don't know the real cause but I'd expect the cause more to be with rod journal size, Max RPM and oil as this things spin 8k RPM and uses a 10w60 oil.

Lane in Tx that would be amazing to get 220k out of the original sleeve. Was yours original, did it have orange o-rings?

George, nice work! When you get caught up less talk about over hauling my motor on the 77R100RS! I think it will be simpler. Good luck.

Hey bGe4orge let me know when the "under 109mph"breakin phase is done, I can stop byAustin to help with the over 109 breakin phase..

http://forums.pelicanparts.com/uploa...1375709215.jpg

George, yep, but IIRC, they were green on the replacement. One question, on a X3, to replace a starter, do you go from below or up top, looks like a PIA either way. I need to do this on my wifes x3. I thought about going in above and replacing all the pcv stuff.

Thanks,
Lane

PM'd you George.

Dee, We'd have to wait until I get my shop built, but definitely!

Martin, I really dont like driving this car at speed, maybe its the tires, but it feels like it needs more caster as it wonders a fair bit when you are trying to keep it straight.

Lane, I assume your replacement is an aftermarket one then as all I have ever seen are black. I'd guess your X3 is a pre-'06? With the crankcase vent valve out of the way (including the throttle body) I'd imagine you would have plenty of room to get it out the top. It really depends on a case by case basis for me as to whether I pull them out the top or bottom but generally they come out the bottom.

Thanks George. It is a 2004. We love the car...have had in deep snow and have climbed some pretty steep dirt hills...hauls cargo and our 5 dogs and with the versi- haul plugged in carries my ktm. Still undecided on the starter...the bendex has been sticking for a while. I wish I could get a couple of drops of oil on it....did that on my RT...never stuck again. Must have been blk. O rings...bought the part from BMW.

Be safe,
Lane

Sticks in the extended position or retracted? My last Z4 had it stick extended and then shorted internally. It cranked the engine until I got the battery disconnected, lol.

Extended...makes the screeetch sound for a couple of seconds after the engines lights off.

Lane

With The engine on the stand the fun begins

http://img.photobucket.com/albums/v8...LongBlock2.jpg

http://img.photobucket.com/albums/v8...LongBlock3.jpg

http://img.photobucket.com/albums/v8...LongBlock4.jpg

http://img.photobucket.com/albums/v8...LongBlock5.jpg



Next The Valve Cover comes off

http://img.photobucket.com/albums/v8.../DisVCOff1.jpg

http://img.photobucket.com/albums/v8.../DisVCOff2.jpg

Then the variable camshaft timing unit (Vanos)

http://img.photobucket.com/albums/v8...sVanosOff1.jpg

http://img.photobucket.com/albums/v8.../DisVanos2.jpg



Then the gears and timing chain

http://img.photobucket.com/albums/v8...sGearsOff2.jpg

http://img.photobucket.com/albums/v8...sGearsOff1.jpg



Then the camshafts

http://img.photobucket.com/albums/v8...DisCamsOut.jpg

http://img.photobucket.com/albums/v8...isCamsOut2.jpg



Valvetrain laid out on the table

http://img.photobucket.com/albums/v8...Valvetrain.jpg

The the head

http://img.photobucket.com/albums/v8...hortBlock1.jpg

http://img.photobucket.com/albums/v8...hortBlock2.jpg

http://img.photobucket.com/albums/v8...hortBlock4.jpg

http://img.photobucket.com/albums/v8...hortBlock5.jpg


Next the rods and pistons

http://img.photobucket.com/albums/v8...sBottomEnd.jpg

http://img.photobucket.com/albums/v8...ockNCrank1.jpg

http://img.photobucket.com/albums/v8...ockNCrank2.jpg

Finally the crankshaft

http://img.photobucket.com/albums/v8...kNBearings.jpg

http://img.photobucket.com/albums/v8...EmptyBlock.jpg


Main Bearings look good

http://img.photobucket.com/albums/v8...inBearings.jpg


Damage to the crank, which is really nothing at all. The speckling you see is material transfered from the bearing. The crank was good to go with just a simple polish job.

http://img.photobucket.com/albums/v8.../DisCrank1.jpg


Parts bagged and boxed awaiting return of the parts from the machine shop.

http://img.photobucket.com/albums/v8...Packaged-1.jpg

Ha :) and I was thinking I'm a "bad ass" replacing head gasket on my girlfriend's bmw few month ago :) $50 on parts and 3 days of fun :)http://forums.pelicanparts.com/uploa...1375759398.jpg
http://forums.pelicanparts.com/uploa...1375759430.jpg

Interesting pics of the S54 M3 type failure. No longer have the pics of the bits and pieces that came flying out of the pan.

http://forums.pelicanparts.com/uploa...1375762616.jpg
http://forums.pelicanparts.com/uploa...1375762635.jpg
http://forums.pelicanparts.com/uploa...1375762659.jpg
http://forums.pelicanparts.com/uploa...1375762680.jpg

George, that's a nice sanitary job!

After you get it sorted out you should reward yourself with a nice long ride!

Did you use plasti-gauge, when you put it together the first time, I am curious what that showed.

I do miss the days when a rope in a tree could pull an engine in a couple hours.

nice documentary I hope this rebuild works great after your done.
I would suggest to make sure to clean the oil ways in the crank with atleast 3 cans of brake cleaner.

NOTE the polishing compound can fill the throws and come out when the engine is running thus taking out all of the bearings BTDT.

You shouldn't use any type of solvent to clean the crank or cylinder bores as it drives the contamination into the pores or grain of the metal. Under the heat and lubrication that contamination resurfaces and could cause problems. Use a soapy solution, dish soap works good, and a good bore brush for the cylinders and small brushes to clean the oil passages in the crank. Nylon type gun barrel bore brushes work very good for this.

So machinists have been using solvent based lubricants for years.... And Sunnen hones use similar lubricants, solvents.

For grinding. Then cleaned for assembly. Or should be.

Dee, For three weeks running I've been trying to drag Geo to Austin's world famous Tuesday Bike Night at Doc's Motorworks on South Congress (@7PM for those in the 'hood who might be interested in attending). He has yet to attend. He's become all work and no play.

I will get him out eventually to hang with the hipsters and their CB360s with clubman bars and straight pipes.

TM1100S, Not that I am the authority on S54 failures but I have yet to see one fail on the #1 cylinder like that, all the ones I have seen are cyl #3 or 4., very interesting, thanks for posting.

Richard, no I did not plastigauge the original bearing. Between the working condition of the rod still in the block with it dangling above my head (still in the car too) and oil still on the components I did not think the plastigauge would provide accurate results. And speaking of time, I can have this engine on the ground in a couple of hours and frankly many of the BMW engines for that matter. The early 2000s E46 chassis I can do an engine start to finish including switching all components in a day. Not bragging just saying while there are now different ways of doing things they are necessarily harder. Now if you wanna swap a 2012 750i Turbo V8, you better give yourself a couple of days, haha, but I know I'm not telling you anything you don't already know ;)

Haha Pauly I know all work and no play. But I've got some things in the works that you might appreciate, i.e. we won't be working on projects at your place anymore, lol.

Pics just posted for entertainment purposes. About $5-7 thousands worth.

TM1100s, what is the story on your engine? Track days, redline, just curious.

Belongs to a local doctor who raced it, in STU class I think.

Everything is back from the machine shop. The cylinder head got a full rebuild including valve job and seals, resurface, pressure checked for leaks and the valve springs were checked for weakness. The block got decked and a light hone. The crank was able to be polished and the bad rod journal cleaned up at 0.0001" under spec of the other journals. The pistons were checked for roundness and are good to go so we will reuse them.

On the subject of rods, I needed 1 rod. The rod cap is separated from the rod be "fracture" method, meaning the cap is literally broken, this creates a more positive engagement ensuring the big end stays perfectly in alignment on reassembly. Unfortunately that means the rod cannot be resized, so the spun bearing rod is essentially now a paper weight. BMW specs these rods in sets matched by weight and will not sell just one rod seperately. So there are a couple of options: 1 used rod, A full BMW set or an aftermarket set. A New set of rods is well over $2000 and is not in the budget, Good aftermarket rods are well over $1000. So that leaves us with a used rod. Unfortunately It is extremely rare to find a good 6 rod set, usually you can find sets of 6 with 1 being bad. Also for this engine there are two rod designs and they are not interchangeable. I decided to buy a set of 6 with 1 bad, thinking I would take the best 6 rods and then have them balanced to eachother. While in the process of doing this I located a good full set of the new design, and purchased those as well. So, now I have my original 6 (1 bad), an early design set of 6 (1 bad) and a set of new design (all good). ARP offers replacement rod bolts for the new style rods so thats what we ended up with, new style rods with ARP rod bolts.

http://img.photobucket.com/albums/v8...lockParts1.jpg


Checking Main clearances

http://img.photobucket.com/albums/v8...ankInBlock.jpg

http://img.photobucket.com/albums/v8...rance2-1-1.jpg

http://img.photobucket.com/albums/v8...Clearances.jpg


End Play

http://img.photobucket.com/albums/v8...AsEndPlay2.jpg

http://img.photobucket.com/albums/v8.../AsEndPlay.jpg


Rings

http://img.photobucket.com/albums/v8...RingGap1-1.jpg

Rods

http://img.photobucket.com/albums/v8...dClearance.jpg

http://img.photobucket.com/albums/v8...Clearance2.jpg


Disassembly and Cleaning Oil Pump

http://img.photobucket.com/albums/v8...lPumpApart.jpg


Oil Filter Housing, Timing cover, Oil Pump, Frt and Rear crank seals

http://img.photobucket.com/albums/v8...ampTCampOP.jpg


Starting Assembly, Crank in.

http://img.photobucket.com/albums/v8...nkInBlock3.jpg


Rods and Pistons

http://img.photobucket.com/albums/v8...ampPistons.jpg


Oil Pump on

http://img.photobucket.com/albums/v8...pInstalled.jpg

Shortblock complete

http://img.photobucket.com/albums/v8...rtblock1-1.jpg

http://img.photobucket.com/albums/v8...rtblock2-1.jpg

Timing Chain, Chain Guides and Frt cover

http://img.photobucket.com/albums/v8...kWithChain.jpg

George, what is the teethed ring on the aft end of the crank...is it part of the crank position indicator? Thanks for the updates....cool stuff.

Lane

Glad you had the crank fixed... in an earlier post you said it looked good after having a bearing welded to it.

Lane, yes that is the reluctor wheel for the crank sensor.

Bill, sorry if I mistyped earlier, the bearing was not actually welded to either part. It had spun and left the crank discolored but not scored enough to catch your fingernail. The other problem is that sometimes the extra clearance will allow the rod to hammer the crank, causing it to bend. Luckily most of my discoloration was bearing material transfered to the surface and the crank was still true and straight.

thanks for updating this assembly blog,
I am going to guess that you spent some time cleaning the crank oil ways.
Goodluck with your build

I have been meaning to update this now for awhile and finally am going through my last photos. The car has been up and running now for a few months and I think we have 2500-3000 miles on it without a single hiccup.

Back to assembly:

Timing chain, guides and cover installed

http://img.photobucket.com/albums/v8...nInstalled.jpg


The Cylinder head is now on and onto assembly of Valve train. First the Rocker arms are mounted to a shaft one for the Intake and one for the Exhaust.

http://img.photobucket.com/albums/v8...ockerShaft.jpg

http://img.photobucket.com/albums/v8...RockerArms.jpg


The rocker shafts slide in through the front of the engine.

http://img.photobucket.com/albums/v8...ockerShaft.jpg


With the rockers on the shafts Now we will install the valve shims. On this engine the valve lash is set with shims of varying thicknesses in 0.04mm increments. Checking and adjusting the valve lash is part of this engines Insp 1 and 2 services (roughly every 25-30k). I recorded the shims on disassembly with the thought that if I reinstalled them they would be close baseline for adjustment. This worked pretty well and most were close to the original shim.

http://img.photobucket.com/albums/v8...ValveShims.jpg

http://img.photobucket.com/albums/v8...ValveShims.jpg

Then the Camshafts go in.

http://img.photobucket.com/albums/v8...sInstalled.jpg

http://img.photobucket.com/albums/v8...Installed2.jpg

Then the Cam gears

http://img.photobucket.com/albums/v8...sInstalled.jpg

http://img.photobucket.com/albums/v8...Installed2.jpg


Rebuilding the Vanos Unit. Vanos is BMW's variable valve timing moniker. There is a company that makes a seal kit, so i disassembled to ensure it was free of metal debris and seals were not damaged. There is a filter at the oil inlet area and it seemed to prevent any debris from entering the Vanos unit.

http://img.photobucket.com/albums/v8...nosRebuild.jpg

http://img.photobucket.com/albums/v8...VanosReady.jpg


Vanos unit Installed and setting the cam timing. You can see the pin in the crankshaft balancer that sets the crank at TDCC for cyl#1. And then on the camshafts there is a bridge looking tool that has pins that drop into the camshafts that lock them in this position as well.

http://img.photobucket.com/albums/v8...sInstalled.jpg

http://img.photobucket.com/albums/v8...ney/Timing.jpg

http://img.photobucket.com/albums/v8...ey/Timing2.jpg

Valve Cover installed

http://img.photobucket.com/albums/v8...rInstalled.jpg


And Installing the Oil Pan, always install the pan last if possible, just in case you drop something down the oil drain back passages or timing chain area. Luckily I've never done that. hahaha

http://img.photobucket.com/albums/v8...yForOilPan.jpg

http://img.photobucket.com/albums/v8...nInstalled.jpg


Car is back in the shop and on the lift

http://img.photobucket.com/albums/v8...ForInstall.jpg


Subframe back out of the car and Engine installed on it.

http://img.photobucket.com/albums/v8...OnSubframe.jpg


Going back up!

http://img.photobucket.com/albums/v8...neComplete.jpg