THE PORTAL HUB - Pinzgauers, Haflingers, Volvo 303s and more!

I'm no flywheel expert, so hopefully others will chime in if I'm wrong. When I was selecting a flywheel for my JEEP, (Sorry VInce, a fact's a fact, and I still like an old CJ-5. I know, I know. Bring on the flame-throwers... ) I chose a heavy one which I understood to be more stable off-road, instead of a light one for quick throttle blips. I didn't plan to race.

Oh yeah, those are cool... I love watching them roll over for no reason.

I'm getting ready to replace my clutch and notice that the pilot bearing is not packed with grease. Is this bearing supposed to go in dry or should it be packed like a wheel bearing? I can't imagine that it would be installed dry. The manual gives no information on this.

Every (both of them!) throwout bearing that I've replaced was pre-lubed. I suspect that since it is sitting in the open, any additional lube would just be flung out (unlike a wheel bearing where the hub contains the grease). You should be able to feel some drag from the internal lube when turning it by hand. Dry bearings rattle a lot when spun by hand quickly and will take a few seconds to spin back down; if you can't get it to spin fast and it stops in a second, max, then you are feeling the permanent lube inside.

I think he was talking about the bearing inside of the end of the crankshaft which supports the end of the transmission's input shaft - not the throwout bearing.

In all the vehicles I've done clutches on - I've put a very modest amount of wheel bearing type grease in the pilot bearing and clean off any excess prior to assembly.

I installed it just as it came out of the package, no grease. The old bearing had no grease, so I'll take my chances. I'll report a failure in the future if there is any. If you Google the question, you get answers from both sides, but most pertain to American cars.

pinzinator wrote:I installed it just as it came out of the package, no grease.

That's what I'm planning to do too. My current understanding is that the bearing is installed as it comes from the factory. My parts have arrived and I'm going to get back at it this weekend.
Ps- I checked the new and old throw out bearings and the new one has some grease inside. The old one spins loosely and is dry while the new has some resistance.
Pps- per the manual, "1. The ball thrust bearing is supplied in greased state and need not be lubricated. 2. Do not wash out ball thrust bearing with grease solvents. If necessary clean with a clean cloth. 3. Make sure that retaining springs fit correctly. 4. Grease inside of clutch release bearing (sliding surface) and release bearing flange respectively only slightly in order to avoid the formation of a pasty mixture... which might lead to blocking of release bearing"

I installed the bearing just as it came out of the package, no grease.
The old bearing didn't want to come out, so Andre came up with an ingenious way to persuade it. Install an anchor and screw in a lag. Home Depot to the rescue!

I'm definitely going to use that lagbolt puller idea. Thanks. Here are some pictures of my slow progress-
Had the flywheel machined- not lightened. I didn't want the machine shop to take much off at all, just a resurfacing. You can see the little bit of a mark remaining in the surface. It looks worse in the picture because you can't feel it at all, but it catches the light.
Rebuilt the leaky clutch slave cylinder. Removing the original snap ring without scoring the bore is a royal PITA. Ultimately, the only way to get it out was with two small screwdrivers working from the top edge and inching (millimetering?) it up the two screwdrivers and out. That sumbitch will be replaced with a standard snap-ring so the next guy has an easier job. I can't think of a reason that won't work. The rebuild kit is simple. I used a light amount of silicone grease in the bore since that worked so well with my locker slave last summer.

you should inspect the groove for the snap ring.
rectangular vs circle .... and use the appropriate shape of ring.

Oh Hotzenplotz... hmm, now you have me wondering. I really don't see a way for this ring to behave any differently than the original. I'll kick that can down the road for a week.
The final step of disassembly was to pull the pilot bearing. Despite Pinzinator and Jim L’s best efforts, I never got the right combination of lag shield and bolt to work. In the end I had to use my aluminum bar and a modified bolt to catch the bearing and get it out.
Next, I turned my attention to the gearbox. The clutch fork comes out easily once you know the trick- roll it off the pivot point instead of trying to pull it straight off. Don't smack it with a hammer! A firm, but smooth roll and it comes off. The small clips come off and that releases the TO bearing.
Finally re-assembly!
I cleaned up all the bearing surfaces for the clutch fork and throw-out bearing. I added some spray on graphite dry lube to the sliding surface of the bearing and gearbox shaft. Added a very small dab of silicone grease to the clutch fork pivot surfaces since they’re sealed up pretty well from contamination. Very smoooth operation now.
Next is pressing in the new main seal and new pilot bearing. Both went in well with silicone grease. Wiped off afterward so there won’t be any gunk build-up from the clutch dust.
(edit) Block the flywheel with a super fancy aluminum bar tool bolted to the flywheel and 1 of the studs.
Now the task of bolting on the resurfaced flywheel… All I can say is WOW!. If you don’t have airtools, then buy the best socket wrench you can afford. After putting blue Loctite (medium strength) on the threads and under the head, the initial tightening with the Harbor Freight torque wrench was fine. You can see how I marked a corner on each bolt. The next 60 degree turn was a huge task. The cheap HF torque wrench with breaker bar was flexing too much to get the full turn. My shorter Proto was a lot stiffer and with the 30” breaker bar did the trick. Jim L says its 240 ft lbs. Those bolts have to be very near their elastic limits. The final few degrees of the turn go slowly and evenly- like the bolt is stretching. I’m still sore today.

Next stop is the clutch and pressure plate. After reading up, there seem to be 2 useable clutch discs available. 4 springs or 6 smaller springs. The 4 spring 733i clutch is upgraded from the stock 6 spring or 533i clutch. Since I plan to upgrade the motor, I went with the HD clutch now. Hopefully the pedal feel won’t be harder than the original. LUK has a good reputation for rebuilt clutches, so I picked up one of those. The stamping is exactly the same- Sachs MT 240. I’ll check my receipts to see where I got the pilot tool, (EI?) but the end diameter was too small for the pilot bearing and I added a few wraps of tape to build it up. It’s pretty simple to put the tool in the clutch disc splines and put it into the pilot bearing. Next, align the new pressure plate on the 3 flywheel pins and start tightening the 6 bolts in a star pattern. I need to put the final torque to them still.

Just to put all the info in one place- Per the manual, the 6 clutch cover plate or pressure plate bolts are torqued to 22Nm per Jim L that's "16-18 ft lbs in a star pattern in 2-3 steps to avoid damage to the cover. Loctite: one drop only on flywheel bolts, none on cover bolts." Hopefully the gearbox goes back in tomorrow!

The gearbox is back in. Using the strap from above really made it simple and easy to manuever the box and turn the drive shaft until the splines engage. Super slick! Next stop- bleed the clutch.

McCall Pinz wrote:Next stop is the clutch and pressure plate. After reading up, there seem to be 2 useable clutch discs available. 4 springs or 6 smaller springs. The 4 spring 733i clutch is upgraded from the stock 6 spring or 533i clutch. Since I plan to upgrade the motor, I went with the HD clutch now. Hopefully the pedal feel won’t be harder than the original. LUK has a good reputation for rebuilt clutches, so I picked up one of those. The stamping is exactly the same- Sachs MT 240. I’ll check my receipts to see where I got the pilot tool, (EI?) but the end diameter was too small for the pilot bearing and I added a few wraps of tape to build it up. It’s pretty simple to put the tool in the clutch disc splines and put it into the pilot bearing. Next, align the new pressure plate on the 3 flywheel pins and start tightening the 6 bolts in a star pattern. I need to put the final torque to them still.

McCall Pinz wrote:Hopefully the pedal feel won’t be harder than the original.

Just an FYI, the springs in the clutch hub have no effect relating to pedal pressure, they are there to provide a slight rotational cushion (impact buffer) between the engine and the transmission. The pedal feel would be affected by a heaver or lighter pressure plate spring.