The Stovebolt Site Forums The Shop Area Driveline Throwout Bearing

I just pulled out the throwout bearing that I got from Classic Parts. It had started making noise a couple of weeks after I installed it. When you shake it, it rattles like a kids rattle. I guess the bearings are loose inside it. I'm going to see if I can open it up just for kicks.
In the meantime, I noticed some scarring on the collar of the bearing. It can be seen here:

[IMG]http://i7.photobucket.com/albums/y261/bohon/56%20Chevy%20truck/TObearing045.jpg[/IMG]

It looks like it was catching on the clutch fork or riding up on it. The fork itself looks OK to me. There are a couple of recessed notches that I assume are supposed to be there. Flat surfaces for the throwout bearing to rest on?
Also, I have a question about lubrication. The manual says to pack the groove inside the sleeve of the bearing with grease. My new bearing does not have that groove. I know I have to lightly coat the surface where the clutch fork rides, but just wanted to know what else I need to do.
Thanks.

Here is the inside of my throwout bearing. Nothing is obviously wrong but as I posted above, when I shook the bearing, it rattled:

[IMG]http://i7.photobucket.com/albums/y261/bohon/56%20Chevy%20truck/BrokenTO001.jpg[/IMG]

But this could have contributed to the trouble. The cage that the ball bearings ride in is made of plastic:

[IMG]http://i7.photobucket.com/albums/y261/bohon/56%20Chevy%20truck/BrokenTO002.jpg[/IMG]

many [most?] ball bearings now have plastic cages, shouldn't cause a problem, but that's likely the cheapest Chinese production, look for a better one at a local store - NAPA has a replacement guarantee, they gave me a complete new clutch kit when my throwout started making weird noises at 11 months .... the manual is talking about the 50 year old style that wasn't a sealed bearing, only takes a very light wipe of grease on the contact surface of todays style

Bill

OK, thanks. Now that I think if it, I believe my rear wheel bearings were in plastic cages, too. I got a replacement throwout bearing from Tim Tygart's. Seems to be much better quality (but still made in China).

So, on Sunday I replaced the throwout bearing. Now it is as quiet as can be. When I first installed it, it made some noise when the clutch pedal was depressed but it soon quieted down. Seems like that was the fix. I also replaced both u-joints while I had the driveshaft out.

I was found this post while researching .... "The manual says to pack the groove inside the sleeve of the bearing with grease". I was concerned because I didn't do that. If its really important I can pull the transmission and get some lube between the throw out bearing and the transmission shaft (I have not started the truck since installing the transmission). How big a deal is it?

Joe

it's a good idea to grease the groove that the fork fingers ride in lightly, none elsewhere, "packing" anyplace would be a bad idea that would result in a greasy clutch eventually - see the actual manual wording here, step 8, 9, 10 .... you don't need to pull the trans again, just weasel in there and get a bit of grease in the groove, none needed on the trans shaft

Bill

That's what I did and my throwout bearing has been trouble free since I started this thread a little over a year ago.

Thanks guys, what I didn't do was "pack the recess" but I did put some grease in the groove where the release fork rides.

Joe

By not having grease in the recess can cause wear, and maybe binding, on the transmission front bearing retainer it slides on. If you can spread any amount of lube on the retainer where the bearing slides you will be OK.
Even if the retainer becomes worn it is no big deal, they are readily available.

Not to ask a stupid question but can I just unbolt the transmission (4 bolts) and pull it back and out? It's a 55 first series so the driveshaft is no big deal.

Joe

It is pretty easy to pull the trans on those trucks.
Go for it!