clutch replacement project, etc.

Sat Feb 15, 2014 11:17 pm

After much preparation I got my '49 Cub split this Saturday afternoon. My first time so took several hours including typical little problems and working alone. The clutch was stuck, so I decided I would replace it (existing are original parts I'm pretty sure). Haven't bought any parts yet. While I have it apart I suppose I'll replace the belts, radiator hose, radiator (leaks), maybe the spark plugs and plug wires and put in electronic ignition in addition to replacing entire clutch including throwout bearing. Some folks mention replacing a seal of some sort presumably behind the flywheel. I'm not sure about that - comments? And I've seen an example of someone who modified the throwout bearing by replacing the graphite part with a chevy bearing insert. How well does that work out? Any other comments or suggestions about what I should do while it is split or comments on something in these images would be appreciated. (this is a great forum!)

thanks much
- Perry
You do not have the required permissions to view the files attached to this post.

Re: clutch replacement project, etc.

Sun Feb 16, 2014 8:45 am

The clutch looks to be decent, by the rust on the imput shaft maybe the disc was stuck on the splines?, that clutch is probably better quality that what you can buy today, even the throwout bearing looks good, clean it up and put it back together,a little lube on the imput shaft and pilot bushing, check finger height on the pressure plate
Tim

Re: clutch replacement project, etc.

Sun Feb 16, 2014 9:07 am

Just from photos only, agree with Tim. Lub the throwout bearing.

I would take a Scotch Brite pad or some very fine steel wool and polish up the fly wheel and pressure plate where the clutch disk resides. Polish as in clean up.

Re: clutch replacement project, etc.

Sun Feb 16, 2014 9:28 am

The seal behind the clutch/pressure plate assembly you are referring to is the rear crankshaft seal. It rests in a retainer which holds the seal in place to prevent the oil under pressure for lubing the engine from excaping around the rear of the crankshaft. If yours is leaking (as mine is) the preferred option is to renew the seal and the modified retainer which is available from Tim (tst) on this site. This will give a better and less costly repair than the retainer which is available through CaseIH. If yours is not leaking, you might opt to leave it alone. Personally, I would replace it while the tractor is split. Cost of modified retainer and new seal should be about $50 to $60 for parts. Good Luck, Stan.

Re: clutch replacement project, etc.

Sun Feb 16, 2014 11:44 am

On the "Chevy bearing insert" you will most likely end in failure. A roller bearing insert is designed to be centered on the clutch fingers. The cub throw out bearing isn't always centered. The graphite bearing allows for some "offcenteredness" without harm.
Look at the pictures in this post and then scroll down and read my post at the end.http://www.farmallcub.com/phpBB2/viewtopic.php?f=1&t=82134&hilit=graphite

I'm not as sure as the others about the TOB you have. Is that a couple cracks I see or just something on it? If you replace it make sure the new one is marinated good before you put it all back together. Cheap grease is a TOB's best friend :||): (second best friend is an operator who doesn't ride the clutch :D )

Re: clutch replacement project, etc.

Sun Feb 16, 2014 12:24 pm

I agree with Scrivet, if the area marked on the photo is a crack and/or a chip. the TOB needs replaced.

Image

To clarify his "marinate" comment a little... hit the bearing with the cheap grease until it comes out the relief hole on the top. Place the TOB in a zip lock bag with several tablespoons of engine oil. Work the oil into all surfaces of the graphite and let it soak for several days, continuing to work it into the graphite. Add more oil if necessary. Make sure the grease zerk is pointed down when you install it.

Re: clutch replacement project, etc.

Sun Feb 16, 2014 11:48 pm

Thanks everyone for all the great comments and advice. I've got some good take-aways now: clean rusty splines and lightly lube, clean clutch faces, no automotive bearing - use original type graphite throwout bearing and lubricate it well, yes it is cracked and needs to be replaced, rear seal - to be determined, but likely to take some action and will need further research on that topic.

There is about 1/16 inch friction material left before the plate wears into the rivets. No more than I use it (turn over garden soil and harrow every year) I may be able to just clean it up, adjust and re-use. Just hard to resist temptation to replace with new while it is apart.

Re: clutch replacement project, etc.

Mon Feb 17, 2014 10:03 am

Be sure to clean up the rust on the smaller splines on the input shaft and inside the friction disk of the clutch. It has to have a slight bit of movement on those splines to be able to release.

Re: clutch replacement project, etc.

Mon Feb 17, 2014 3:05 pm

I would definitely replace the rear main seal while you have it apart. The clutch and pressure plate are probably good for quite a few more years. Looks like the throw out bearing definitely needs replaced, and another caution to install it with the grease fitting down (BTDT). I would also take the flywheel and have it surfaced. I think that you will probably get a lot more hours out of your clutch with a fresh surface. Any good automotive machine shop should be able to grind the flywheel for a reasonable price. You might also look at the pilot shaft bushing in the end of the crank. If it has excessive play it can cause the clutch disc to wobble around, which makes a funny noise when you have the clutch pedal in. Good luck.
glenn

Re: clutch replacement project, etc.

Mon Feb 17, 2014 9:52 pm

What do y'all use to clean the rust on the inside (in the hole) splines? A toothbrush probably is not ideal. For the splines on the shaft I can use a steel or brass brush, but I don't know about what I would use on the splines in the hole.
thanks

Re: clutch replacement project, etc.

Mon Feb 17, 2014 10:46 pm

Dremel with a brass brush??

Re: clutch replacement project, etc.

Mon Feb 17, 2014 11:00 pm

I went with the chevy style bearing in mine about two years and a lot of hours ago and have had really good luck with it.
Just machined out the graphite center on my lathe and pressed the roller type in .
Just a different way to do it.....the graphite type has proven it will hold up fine over the years with proper maintenance.
I would agree with the above comments to resurface the flywheel, change the rear main seal and swap out the pilot bushing while your in there.
Good luck !

Re: clutch replacement project, etc.

Mon Feb 17, 2014 11:34 pm

Fireman Bob wrote:I went with the chevy style bearing in mine about two years and a lot of hours ago and have had really good luck with it.......
I'd say you're lucky and have the bearing centered on the clutch.
Fireman Bob wrote:..........Just machined out the graphite center on my lathe and pressed the roller type in......
Is your chevy bearing pressed into the graphite or into the metal housing?

Re: clutch replacement project, etc.

Tue Feb 18, 2014 11:20 am

I machined the small end collar off the auto bearing so it was the same dimension for the length of It that went into the graphite. I then opened up the previously damaged graphite to that size. The auto bearings big surface actually rests against the old metal collar that held the graphite before. The old graphite now takes no force but just acts as a centering method for the auto bearing.
While there will be some lateral/radial movement between the clutch fingers and the bearing if everything is not centered both of these surfaces are hardened to over Rockwell 55 and should easily tolerate this.
I am not disparaging the graphite system but almost every clutch throwout system in the last 50 years has used a roller bearing with great success.

Re: clutch replacement project, etc.

Tue Feb 18, 2014 1:24 pm

TrentonJ wrote:What do y'all use to clean the rust on the inside (in the hole) splines?



Try spraying it with WD40 and scrubbing with a regular or a wire bristled toothbrush.

If that doesn't work, try to find some Naval Jelly.