Rok Shifter Issue oil leak behind clutch

Hey guys. Ive just noticed this oil leak coming out the clutch. This is about after a day of running. Im assuming its a seal of some sort, but is this something that i can fix relatively easily or am I going to the engine builder?

I have attached pictures so you all can see whats going on. Thanks for any help.

I would pull the pressure plate and clutch disks off to inspect and see if you can find a definitive source for the leak. Could be one of two seals (part 129 or 143). Usually oil seals are not too hard to pop out and replace, but I’ve not done these particular seals before so take that with a grain of salt.

You may also want to double check that the gearbox is properly ventilated. I would remove the black vent fitting and just run a longer piece of fuel line down to the bearing hanger on the chassis.

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I’m curious if anyone else has had this problem before, and if so what you did to fix it.

That’s a good thought on those oil seals. I’ll pull it apart this weekend and see what’s what.

Most likely oil seal at base of the clutch housing. If it was getting pressurized from something else it would just blow out the breather.

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Though I’ve never seen that seal go bad on any kz/rok engine so may be worth taking a look at the other seals.

engine is clean other than that but I’m definitely going to check it out!

This is exactly what mine did, Jake. This happened when my vent didn’t vent enough (I put a new-line catch bottle on it and forgot to drill a hole in the cap for it to vent).

You either need seal # 129 or 143. In my case it was 129.

It’s an easy fix.


This is awesome thank you!

Now, I’ve gotten as far as getting the basket off last night, and am puzzled by the best way to remove the damper cover. Is it best to just take the entire primary transmission off the side of the motor or can I unbolt the damper cover and not screw anything up? The big black seal is located behind this.

Okay heres where im at. I need to replace this seal. Its impossible to pull out with a pick and ive destroyed it doing so. So either way, its gotta get replaced.

Is there some technique? Its in there SOLID. I am at the point where im debating pressing it out.

Theres one more cover you can pull off before needed to split the cases im pretty sure. The cover with the vortex logo on it in the right side of your photo.

so the primary transmission cover that’s got the big gear in it?

Nevermind that’s not needed. Only thing I could think of its blowtorching the metal around it to get you a little more clearance to pry it out.

Actually it is! I ended up pulling the cover, being careful to leave the primary transmission gear in place. Then i just tapped it out lightly with a screwdriver and a hammer. The pick just wasnt cutting it. It made it a LOT easier.

Awesome! If you ever need to tear it down further, OTK has disassembly and reassembly videos on YouTube…