Input shaft+ pilot bearing 10, me 0

[xcastaway]

I've been trying, whenever my arms and shoulder permit, to convince my gearbox input shaft to mate with the pilot bearing in the back of the crankshaft Three days worth of trying. I've pulled the gearbox down and double and triple checked everything at least twice. The new LW flywheel, clutch and pressure plate and pilot bearing are all installed correctly, the pilot tool goes in and out, though it's pretty tight, the t.o. bearing is seated properly, and yet, try as I might, I can't get the gearbox closer than an inch of where it needs to go. Doing this primitive style, on ramps and jackstands with a jack with too small a pad for comfort holding the gearbox up. I checked to make sure the pilot bushing and clutch disk fit on the shaft before installing. The bearing is a tight fit, so I need to get it aligned perfectly to get it in.

Anybody have any tips for managing that perfect alignment? I fear I'm approaching insanity, trying the same things over and over again, hoping for a different outcome.

I needed to get this done before I got too old to manage it. I"m afraid I waited too long, at least for this step.

[moroza]

Two ideas come to mind:

1. Rent a transmission jack, likely free.
2. Something I've done when I had no alignment tool - thread the pressure plate bolts on loosely, just barely tight enough to hold the clutch disk from its own gravity, but loose enough to be able to slide it around. Gently use the transmission input shaft as an alignment tool, loading the input shaft radially to move the clutch disk around until the pilot stub finds the pilot bearing and you're able to fully seat the trans. Remove the trans and carefully, in a star pattern, tighten the pressure plate.

[xcastaway]

Thanks for the reply. I'm currently a pedestrian, so I'll have to make do with the pos jack I have. I never considered that I might be able to rent an actual tranny jack. And a variation of that second approach was what I had just about resigned myself to having to try. The pilot tool was a pretty sloppy fit into the bushing, so it is likely why I'm that hair off. I'm gonna try using it to try to center it up better using your approach first, pry the disk to as close as possible to alignment. A precariously perched tranny is a poor precision tool, I'm not sure I could get it back out without disturbing the disk. I may have to try, if the first try doesn't go so well.

Thanks once again for your help!

[xcastaway]

I think that was probably it. I loosened it back up and did my best to center the disk with the pilot tool. I'd done this initially, and still spent two days without hitting that hole, but I had the clutch off again yesterday to make sure I'd done everything right, and let too much weight press on the tool before tightening it up. So today's wounds are mostly self inflicted. The pilot tool at least goes in and out easily now. I couldn't test it with the tranny because my arms are so dead I couldn't get it on the jack. Time to quit for the day.

[xcastaway]

My adversaries are running up the score on me. Now I'm 3/4 of an inch away from getting this darn thing back together, which isn't much better than a mile. I loosened the pressure plate bolts and spent a lot of time getting it as close to dead centered as possible, to where the pilot tool slid in and out with next to no friction, and still no joy. As awkward as my situation is, there is no way I could use the input shaft to adjust the clutch plate and pull the gearbox out without disturbing it. And I don't think I could get it any closer than I did with the pilot tool. It only moved a fraction of a millimeter in either direction from where it was when I fruitlessly spent yesterday trying to install it. It was close enough to the correct size for the pilot bearing that a wrap of electrical tape wouldn't fit. Were I ever to do this again, I'd saw off the input shaft from a boneyard gearbox to be sure of getting it exact.

My poor senior citizen arms are dying here, it's a good thing this is the final major mechanical task I'm ever gonna attempt. For now, I shall endeavor to persevere, once my arms start to work again. I need my car back.


:(

[a777fan]

So you did confirm that the pilot bearing fits over the input shaft end prior to installation in the crank?

I just did this on my 540 and didn't have any issues. The tranny slid 'right' in. I mean it did take some finagling, but nothing like what you are describing here. What brand pilot bearing did you go with? OE? or something else?

[xcastaway]

Yep, I checked that both the clutch disk and pilot bearing fit the input shaft before I put it in. The bearing was identical to the one I pulled out, that only had 13k on it. I'd have to dig thru my records to find out what brand, but it wasn't junk. I used the new one that came with the clutch. Unfortunately I had exactly this issue when I first swapped in the 5 speed. Then the sucker wouldn't go in either, until I gave up and gave it a final shove before crawling out and it slipped right into place. I've done a number of non bimmer clutches and never had the slightest issue.

I knew it was a mistake to install the used clutch from my donor car, but I had no choice but to do it. It's PO had stuck a new disk in with a used pressure plate, rounding off most of the bolts in the process. It never quite worked right. My auto ate itself before my wallet was ready, so I inflicted this repeat performance on myself.

The bearing is nearly press fit on the shaft, anything short of perfect alignment and it won't go in.

[a777fan]

Odd!

I did not check the pilot bearing on my input shaft before install, but the fact that yours is 'press fit' tight doesn't give me warm fuzzies. There is an awful lot of positioning 'slop' when you are getting these things aligned that I can't believe a press fit pilot bearing would work. (And I guess your experience is somewhat validating that? Sorry.) For what its worth, I put mine back together using a jack and a piece of plywood with a hole which made it a little more stable. No laser sights or anything like that needed.

Might there be something odd about your input shaft? Has the car always been a 5 spd? IE- is the tranny original?

[xcastaway]

It's a Touring, so it had an auto originally. It's just nearly press fit, it will go on, snugly, by hand if exactly aligned.

With my last reserves of brute force, I got it to within a half inch, which I hoped meant it had at least started into the bearing. Then, with great trepidation and very carefully, I drew it flush using the bolts. It went in without using any force on the bolts, gently. It couldn't have done that without going into the bearing, I'm pretty certain. So I'm going back out and putting everything back together. I"ll be uncertain until I put the slave cylinder in and make sure the clutch disengages, and won't be positive it's right until I drive it away. Oy!

[xcastaway]

It seems to disengage, but feels different, which it is. Still a ways to go to get to driving away in it.

[consti2tion]

Looks like you’ve got it in, but for future reference did you apply any sort of grease on the input shaft/splines? Not talking about covering them just a light film to help ease them into place.


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[xcastaway]

Yes, I used a light smear of moly di grease on the inside of the bearing, the splines and the input shaft. I'd hoped to avoid the nightmare I had the first time I stuck this gearbox in. I'm hopeful that it isn't possible to shove the pilot bearing into the crank beyond the reach of the input shaft, in which case I did get it in, and as soon as I find the energy to finish the install, I'll have a car again. I'm not counting on anything at this point though.

[moroza]

I've never had this exact issue, but back when I was doing my 544 build, there was a fiasco (https://www.bimmerforums.com/forum/showthread.php?1330497-M62-pilotbearing-starting-to-piss-me-off) (also here (https://www.bimmerforums.com/forum/showthread.php?2233974-differences-in-535-and-540-pedal-boxes&p=28860527#post28860527) and here (https://www.bimmerforums.com/forum/showthread.php?2373715-New-clutch!&goto=newpost)) with dimensional errors in pilot bearings, including one from the BMW dealership. NTN ended up being correct. Three or four others - IIRC, they were FAG, Bremi, SKF, and Febi - were either 9mm or 3/8" thick when they should've been 10, and were a finger-loose push-fit into the crankshaft hub, allowing removal with my fingers, when they should've been a light/medium press fit. I didn't try putting them on the trans input, but the other two dimensions being wrong suggested a more systematic problem with these particular parts.

Also, see here (https://www.bimmerforums.com/forum/showthread.php?1717650-Gearboxes).

I wish I could tell you what pilotbearing I successfully used for my M50 manual swap, but it was a flywheel-mounted one that came with the Valeo SMF conversion for a 37BZ, totally inapplicable to you.

[xcastaway]

You've brought up something I decided not to worry about, though maybe I should have. When I pulled the auto's pilot bearing out of my crank, I had to pack the crank pocket behind the bearing with grease and force it out tapping something I had that fit into the bearing, using the grease to force it out. I had to gently tap the Getrag's bearing into place. I was expecting to have to do the same process to get it back out, but the snug fit on the input shaft pulled it out when I removed the gearbox. The new bearing I managed to press in with firm thumb pressure. It's in there solidly, I couldn't remove it by hand once it went in, but it isn't quite as snug a fit as the auto's bearing was. However, given the issues I had getting that damn shaft to go into it, there is no way I'm going to take it back apart to see if I need to do anything about it. The new bearings dimensions are exactly the same as the one that came out (eyeballed and finger mic'd, not using micrometer), and I didn't notice anything that gave me any concern that it wasn't doing it's job of holding the input shaft right where it belonged in the 13k miles I put on it. So, I'm going with it as is. I didn't check to be sure, but I don't believe the bearing will push so far into the crank that it goes beyond the end of the shaft, so I'm expecting to be good to go once I finish assembling it today.

I couldn't seem to hold onto anything due to dead hands yesterday, so I took the day off to let them recover. It is going back on the road today, come Hades or flooding. I hate being stranded.

[ross1]

I don't have a BMW pilot bearing in front of me to look but is does one end have a chamfer and not the other? See where I'm going?
A friend just had a similar experience with another type vehicle, one with the bronze bushing type. He had been trying to stab in that trans for hours with no joy.
He called me to help and for ideas. It seems SOMEBODY had installed the bush back asswards and unless the shaft was perfectly aligned it wasn't going in. Since no replacement was on hand and we feared destroying the bush removing it we persevered and finally got it to go.

[xcastaway]

An excellent thought, I had to go out and get the bearing I had pulled out to check to be sure. Alas, it's exactly the same on both sides, no chamfer at all. I hope I'd have noticed if it weren't, but... I'd have preferred your suggestion to have been correct, so I'd at least know why it proved to be such a bear to get that sucker installed. As it stands, I have to chalk it up to evidently having been a horrible person in a past life. Oh, well, in a few days it will have been an adventure doing this, whereas at the moment it's still a nightmare.

I still have the driveshaft and exhaust left to install, a BAD case of vertigo and a truly pissed off Montezuma stopped me dead in my tracks last night, and crawling back under there feeling like I've had several drinks too many, and the possibility of urgently having to run out from under it are making finishing it less than an enticing proposition. Mid 90's, and directly in the sun until later this afternoon convinced me to wait until then to tackle it.

The one main reason I prefer doing my own work, even with nightmares such as this has proven to be, is that I always know who that SOMEBODY was and exactly what he did wrong or right on any given project. The 2 grand I was quoted for this also had something to do with it.

Thanks.

[moroza]

I wouldn't worry about it at this point, but I suspect a systematic problem with bearings made to interchange with BMW 111211720310 (all manual M5x and M6x, among others), such that they end up slightly too small in ID and OD. My guess is American units are at the root of the problem; IIRC, one of the wrong ones measured exactly 9.35mm (3/8") thick.

Maybe you could've put the pilot on the trans and guided it into the crankshaft end when mounting the transmission?

Automatic pilot bearing? :confused Autos don't use pilot bearings...

[xcastaway]

If the bearing would fit thru the clutch disk I'd have certainly tried that during this fiasco. Puzzling, I did pop out a bearing as described, and I can't imagine why I would have yanked the one out of the donor car, I certainly didn't use it. Oh well. The SAE/ metric conversion issue was enough to screw up NASA, so it's not that big of a surprise if it hit BMW suppliers as well.

New thing to worry about. A nearby neighbor, whom I had a long, socially distanced , though mask-less, conversation with last week, went out of here by ambulance in bad shape with covid symptoms yesterday afternoon. My second exposure, I think I may have had it back in March.

I couldn't bring myself to crawl under there and finish the car yesterday, and now, after the 50 mph gusts we had last night, I have to sweep tree parts and dozens of pine cones out from under her before I can do anything. I've a new dent in my fender from a 3 inch thick limb that shattered on it. Good thing I'm not that concerned with external appearances on this old girl.

[xcastaway]

Post script:

Just out of the shower after finally getting the Touring back on the road. The disassembly went perfectly, and the reassembly was exactly the opposite. Every single thing put up a fight, but it runs, and it feels a lot perkier with the lw flywheel. The clutch itself feels way stronger and more solid than the Luk with the pressure plate on at least its second disk. I didn't notice, in the short test hop I did, any of the odd noises from swapping to a single mass flywheel. I went with a sprung hub disk to try to prevent it. I installed my old exhaust that did a muffler self delete ( it fell off and became a pile of rust dust as soon as I undid the rear mounts), and it isn't as loud as I feared it was going to be, and will be better yet once I get the pipes extended to the rear of the car.

I'll need to go thru Bentley and find out what options for adjusting the clutch there are, I know I saw at least one, since I'm not thrilled with the engagement point, and the first 4 or 5 inches of pedal travel do diddly. It's pretty much fully engaged an inch off the floor. I'll play with that once I recover from this part. It's driveable as is, and I've had my fill of being stranded.
This is the clutch I stuck in, though I paid $100 less for it. Its been sitting on my table since last August waiting for me to get around to installing it.

https://www.ebay.com/itm/CM-STAGE-2-HD-CLUTCH-KIT-CHROMOLY-FLYWHEEL-FOR-BMW-E36-E34-E39-M50-M52-S50-S52/132617773337?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

[ross1]

Clutch hydraulics may need to be bled some more.

[xcastaway]

Great! I was discouraged after looking at the pedal adjustment which is all Bentley had to offer. I'll give that a shot, thanks!

[abakos]

fwiw on my E34 the clutch pedal was spongy after swapping the master cylinder. I bled it several times over and it stayed that way, but after a couple days it fixed itself. My theory was that there was some air trapped, but it eventually work it's way back to the reservoir.

I also had a problem with getting my input shaft into the pilot bearing, but it was because an idiot mechanic used a hammer on the input shaft to help get the housings apart and it was mushroomed ever so slightly. Fine sandpaper and a sanding block cleaned it up. Doesn't matter for the OP now I guess, but putting it out there in case it helps someone else down the road...

[ross1]

fwiw on my E34 the clutch pedal was spongy after swapping the master cylinder. I bled it several times over and it stayed that way, but after a couple days it fixed itself. My theory was that there was some air trapped, but it eventually work it's way back to the reservoir.

.
They do tend to self bleed with use. Pumping the pedal about a billion times sometimes works too.

[xcastaway]

Bleeding it did wonders, though either it will bleed it self a bit more, or I'll have to try, try again. Thanks, Ross1.

Other things are now a priority, as the evac zones from the fires are marching my way. I hope Moroza got his important possessions out of where he was living, last I saw him. He was square in the middle of a mandatory evac zone, and unless he got real lucky, that area is likely gone. (edit: found a better map that has his area in the yellow zone, get ready to run status. Hopefully, it won't reach either of us!) I have no way to get anything that won't fit in my car out of here, and if the fire jumps I-5 I'll have only those things left. I've already got that car load picked out and ready to pack. Home not insured, so it's gonna hurt. Really hard to breathe outdoors now, and none too easy inside.

Fortunately, my mechanic/parts changer isn't quite that big an idiot, so my input shaft is undamaged, just stubborn.

Wish us left coasters luck, it appears we're gonna need it.

[a777fan]

Glad to hear you got it back together and its drivin around.

Best of luck with the fires down there at the moment. Hopefully the winds shift and they begin to move away from portland and the suburbs.

[xcastaway]

Me too! If I hadn't managed to get it done before the smoke settled in, it would have to sit until at least Tuesday, when hopefully the rain they are calling for gets here. Hard to breathe outside, and not all that easy inside. If it doesn't rain, the air around here is going to remain awful for a while. Thankful the winds have died out, less worried about fire reaching me now. Hope Seattle avoids our issues.

[tortexal]

Responding to this old thread in case others in the future also get stuck with this. I just went through the same battle on and off for 2+ weeks on my 535i. My old bearing was very snug on the input shaft, and so is the new.

Tips:

1. Use a clutch alignment tool when installing the pressure plate.

2. Use a transmission jack with up/down and left/right tilt.

3. Put two bolts opposite of each other on the transmission to use for eyeballing the correct pitch and rotation of the trans. (Not doing this cost me 2wks of lost time)

4. With the trans in gear, raise and start tilting to eyeball the alignment. Once it looks right, start wheeling the trans into the clutch disc. Use your hand on the output flange to shimmy the input shaft into the clutch disc. You'll hit a road block with 1/4-5/8" of gap between the bell housing and the engine. Congrats you've hit the pilot bearing. If your bolts are off from their holes, note if they're missing from the top or bottom. Back the trans out and adjust your rotation and try again

5. Put the trans in neutral.

6. Use your arms to wiggle the thing fwd to get at least one bolt to start threading by hand.

7. If you cannot get the other bolt to thread, find the next nearest bolt that'll thread in by hand from step 6.

8. Snug these bolts in by hand (no wrench or ratchet). Your alignment is now correct.

9. Wiggle more and see if you can get any other bolts to start threading in by hand. If not, snug the bolts from #6 and #7 more w a ratchet by hand (DO NOT tighten these in all the way, you want to "pull" the trans in as evenly as possible). The trans will start to slide into the pilot bearing.

10. By this point you should be able to install the remaining bolts and start snugging things up on opposite ends of each other until the bell housing sits flush all the way around.

You should be able to work your way around the bell housing adding and very lightly hand snugging the bolts until the trans works its way in. There should NOT be any resistance anywhere when turning these bolts by hand. If you think you have to apply torque to anything, stop and fix the alignment of the trans. Worst case scenario your pilot bearing really is out of spec and you'll have to pull the clutch/flywheel/bearing and get a new one that's in spec.

The tolerances on the pilot bearing are very tight and the trans is not as easy as other auto mfg's to install.

Good luck!

[xcastaway]

Ya gotta love reliving your nightmares!

The main thing I learned from my ordeal was covered with your:

2. Use a transmission jack with up/down and left/right tilt.

I started my clutch replacement on the spur of the moment, when I learned the park managers were going to be gone for the weekend (we aren't allowed to work on vehicles here). I should have grabbed a rental tranny jack before even considering tackling it. Most of my issues stemmed from trying to hold and balance the gearbox on the 2 inch pad of the little floor jack I had available, which made getting things aligned correctly a challenge, not to mention dangerous. I nearly dropped the gearbox on myself several times during the process. The worst part is I knew better, having had the same issues getting things aligned when I first did the 5 speed swap.

I did follow most of your other steps and gently drew it into place. If I ever feel the need for self abuse again, I'll make certain to have the correct tools (tranny jack) on hand before touching a wrench. Hopefully, this clutch will outlast me, it feels quite solid, even though I still don't like how it engages. I'd go with a sprung hub Sachs clutch were I to do it again.