Guys,
I finally found a engine for my blown up Cat 12 70D. New to me engine includes A 80C243 grader in better shape than my original dirt cutter. it has been sitting for several yrs and clutch is stuck on her. has electric starter. puller the left hand cover off clutch housing and got the engine barred over and trans in neutral . What is the preferred method of unsticking a wet clutch?

Thanks

John Perry

Hi, Ace Flyguy.
If you have anything handy that will tow it, you could try towing it with the transmission in the lowest gear you can find and the clutch pedal depressed. You can get the blade a little way off the ground by using the electric starter to wind the gears over. If it has a decompressor, it will make it easier on the starter if you flick that to the decompress/start. position.

If my memory serves me rightly, it is not a good idea to try squirting any form of 'loose juice' in there 'cos the clutch shares oil with the engine. Unless, of course, you plan on doing a full engine oil and filter change anyway.

Just my 0.02.

Deas,
Thanks much . will try the ole girl when i get back home from work in 1 1/2 weeks. yeas she does have the decompression. I will probably add some atf down the stack and let it sit for a day then turn her over Engine was stuck but i got her to bar over. Im wondering if after i get her started and warmed up if i can get her to start in low gear?. i have about a mile and half to drive run her to my place. hopefully get the clutch broke free by then.

Thanks guys

John Perry
BLOWN UP Cat 12 70D3233 / Cat 12 80C243 / ford 8N / Case 580C / Cessna 170B /

Hi, Ace Flyguy.
I have never had a stuck clutch in a grader, wet or dry, and so have not had the opportunity to try shifting on the run using the engine revs to get the gears in or out. These machines have gear locks that are engaged and disengaged by an extension of the clutch linkage. What I do not know is whether this disengagement is dependent on the clutch actually disengaging or whether the extension linkage will disengage the gear locks even if the clutch does not disengage. I suspect that it will but I just do not KNOW. IF you can move the gear levers through their cycles with the clutch pedal fully depressed, then I think you would be able to change on the run using the engine revs - if you can get the machine started and rolling.

You might also find that a decent sized pickup or small truck with some weight in the back would be able to tow start it in a higher gear. I once tow started a Cat D4D with a 5-ton 2 wheel drive truck with about 1 ton of load on the back. You may need somebody to flick the decompressor closed once you get the grader rolling.

Just my 0.02.

Hey Deas,

MMMMMMMMMMMMM pull starting a machine with a stuck clutch, how the hell do you uncouple it? My best guess would be to start it in out of gear by starter motor, warm it up, then shut down, put in first gear and start again, would help if you can have some slope assistance and a long road ahead without obstruction. I have unstuck a twin plate dry clutch like that in a truck, drove along a bumpy road with my foot on clutch pedal, it let go pretty quickly.

Wombat (my 0.05 worth, happens to be smallest Oz currency)

Had 12E 21 F wet clutch stuck a few years ago. Started engine to warm it up a bit then push started with it in gear from behind with a wooden post in front end loader bucket. Worked it pretty hard for 15 - 20 min utill it let go, did not think it was ever going to release but decided to finish the job then lo and behold it was fixed. Had plenty of room to turn around at the end of a 500 yard run. No problem since.
Another 0.05 worth from Oz

Hi, Wombat.
I was thinking in terms of King of Obsolete and his chains to the drawbar pins of his tractors to enable him to uncouple the tractor if it goes through the ice so that it doesn't take the sled train with it but I forgot to mention that part. Thanks for reminding me. Might be that CRAFT disease is setting in.

Just my 0.02.

Are you getting pedal travel? Transmission has an interlock so clutch pedal needs to be depressed to change gears whether it's running or not. Is it in gear or neutral now?

When I first looked at the grader it was stuck in reverse from when it had been backed into the woods to rust away forever several yrs ago. I worked both the gear shift and the high low range shifter and got it into neutral. Yes i can depress the the clutch pedal. I took the left side cover off the flywheel clutch housing and confirmed that when pedal is depressed it is operating correctly. I think when I get her warmed up and then moving she should eventually come loose. I can run down my runway and back have enough turn radius and 2800' long each way so will work her hard once warmed up and see what happens. and yes I can shift thru all the gears when not running also. I will run her for the first time in after 11-3 when I get home.

JP