Oil Leak from Clutch Actuator

9 replies to this topic
  • smdonald

Posted May 09, 2011 - 07:37 AM


Hey all. Just finished a build on a backet case 01' 426. Started up great and runs like a champ but when I pulled the clutch lever in for the first time, oil gushed out of the seal on the actuator shaft. I used Moose gaskets and seals that came w/ a kit for the engine. I thought that maybe the actuator seal from Moose was out of spec so I picked up an OEM seal which made no difference. Maybe the shaft itself is worn out?? I havent seen this before. I dont really know how oil flows through this part of the engine, but im starting to think there is a blocked oil passage somewhere in there, and when i pull the clutch it forces the oil up and out of the actuator hole. What do yall think??

Also, the cluch pushrod assembly didnt have the ball bearing in it when i tore it apart. I ordered one to put it back to how i thought it is supposed to be. But when trying to put the pressure plate on w/ the ball bearing, the assembly is too long, and the pressure plate wont sit flush w/ the plates like it does w/o the ball bearing. Any thoughts? Maybe and aftermarket pushrod that is longer to accomodate no ball bearing???

  • grayracer513

Posted May 09, 2011 - 08:07 AM


The clutch release arm bore is used to connect the oil passage coming from the main shaft with the one leading to the output shaft. It therefore carries high pressure lube system oil, so the pressure you see is not abnormal. The leak is, though, and unfortunately, it's probably more a matte of the case being worn that the shaft. If that turns out to be the problem, a good machine shop should be able to bore the hole oversize and install a bronze or aluminum bushing to make everything fit right again.

  • smdonald

Posted May 09, 2011 - 09:02 AM


Thanks gray. It seems that the seal fits properly into the case. Not sure how to test that w/o trying a new shaft. Here's a question: i was looking through some parts microfishes just now, specifically at the clutch pushrod assy...i may have the rod in backwards, which may be causing the dimensional problem i stated about using the ball bearing vs. no ball bearing. If the rod is truely in backwards, can this somehow cause the oil to force its way out the seal? And also cause the length problem??

  • grayracer513

Posted May 09, 2011 - 09:12 AM


The rod can't cause the problem. The issue is also not whether the seal is loose, but the shaft of the actuator/release arm. If it is loose, it will tilt in the bore when used, and move too far for the seal to hold oil in.

  • smdonald

Posted May 09, 2011 - 10:57 AM


so the first attempt at fixing this problem would be to get a new actuator shaft?

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  • grayracer513

Posted May 09, 2011 - 02:46 PM


I think the first step would be a little more diagnosis. Does the top of the shaft tilt noticeably when you work the clutch? If yes, then that's the problem, and you need to find out why.

Remove the seal and the shaft and examine the bore to see if it's obviously out of round. Also check the shaft for wear, but there's no reason to think the steel shaft would wear faster than the aluminum case.

  • smdonald

Posted May 10, 2011 - 05:46 PM


so i just looked at the bore on the shaft and can notice no "out of round" characteristics. the shaft itself "looks" ok, but we all know that just looking at a part doesnt make it OK. i watched closely while pulling the clutch lever and cant see any unusual side to side movement. im stuck on this one. i have no idea weather to just buy a new shaft or to tear down again and do what you said gray, and have a machine shop bore it out and insert some bushings. what do you think? the latter option would obviously require a ton of labor and time. i didnt have the shaft in wrong either. i tried using the ball bearing again and comfirmed my original statement, that it is too long w/ the ball.

this has been racking my brain for days. this is the 4th 426 ive done, and i havent seen this before. gray, have you seen an oil leak from this area before?

any advice helps guys!! im dead in the water.

  • gscx

Posted May 10, 2011 - 05:51 PM


There is a bearing just underneath the seal. I would try replacing that if everything with the shaft is fine

  • smdonald

Posted May 12, 2011 - 05:50 AM


going to replace the bearing tonight... will post results

  • smdonald

Posted May 13, 2011 - 07:43 AM


bearing replaced...leak stopped. now on to jetting. thanks everyone!

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