Oil leaking at the cam cover - KZ1000

Hi Patton,

Z1E gaskets are what I use too. I guarantee it will leak with a new, dry gasket. There's something else going on here.

I notice that the leaks are always on the left side (cylinder 1) regardless of how the cam cover is put on. In other words, if I rotate the cam cover 180 degrees and put it on, the leaks are still on the left side of the motor.

One thought I had is that maybe the oil drains on the left side of the head are clogged. I don't know exactly where the oil drains to, somewhere down where the buckets are I guess.

Per FSM:
If the crankcase vent breather hose or the parts inside the breather become clogged, pressure may build up in the crankcase and cause oil leaks.

If a non-stock vent hose is fitted (such as running to exit underneath the bike), would assure it isn't kinked or blocked. The interior diameter of the hose should be large enough to fit over the crankcase vent nipple. and continue with the same i.d. until exiting underneath the bike.

If a small filter is fitted to the crankcase vent, would assure the filter is freely flowing.
(I'm not a fan of such filter.)

If not already done, would assure oil is fresh, of correct weight/viscosity, not overfilled, and not fuel-contaminated.

Would also use only 100% dino oil, and not synthetic oil which reportedly may leak from places where dino oil doesn't.






Good Fortune!

The female-threaded holes in the head where the cam bolts screw into are dead-end holes.

Am wondering if maybe one or more of the closed-end holes isn't completely clean inside, because anything in there will prevent the bolt from going in as far as it's supposed to, which would feel tight on the bolt while not tightening down the cover.

Could use pressurized carb cleaner spray to squirt down into the holes and clean them out.

Another thing to check is that the bolts aren't too long, and feeling tight when actually bottoming out against the dead end.

Good Fortune!

I tried Wireman's technique and with great hope went for a ride and... the cam cover still had leaks.

If you've been following this thread you know I had been trying to fix this dribble for months!

Last week I went to the local mechanic, very experienced. He worked on my bikes when I was in college, 30 years ago. BTW - if you're in Honolulu, the shop is Cycle Tech, at 2457 South King Street (808) 955-4180.

Al (the mechanic) was eating lunch at his desk when I stopped by. I talked to him about the problem and he went over to his tool box and pulled out a tube of Three Bond 1211. He said if I coat the surface evenly with this and then see it squeezing out when I put the cover on, it WILL seal.

So I went and found the 1211 - not easy to find and $20+ per tube. First I cleaned the cam cover and the head surfaces with acetone. Then using a new cam cover gasket, I coated the top and bottom of it on each of the four ends (where the cam end caps are) and put the gasket on the head. Then I carefully put the cover on, torquing the bolts finger tight.

The tube says 1211 cures fully in three days. I waited four days to be safe and because I have other things to do besides work on my motorcycles. I torqued the cover down using a wrench, approximately to spec (I don't have an inch-pound torque wrench). Then I went for a ride. No leaks!

And I went for another ride today. The areas that were leaking before are now dry as a bone.

There you go. If you have a stubborn leak, try Three Bond 1211.

Glad to hear its not leaking, but you shouldn't have to glue down the gasket, only a bit over the end plugs. But hey if it works, get out and ride it.

Three Bond works great, I use 1104. But I've never had to use it on a cam cover on my 1000.
Motor Head, good discussion using epoxy to fill low spots. we use JB weld and wax paper instead of the plastic zip lock baggie. good method, thanks for posting that on the board.
Kapa, did you check to make certain the bolts weren't bottoming out the last time you had the cover off? Patton may be on to something. Hope it stays dry for you.
Nothing worse than a pesky cam cover leak :pinch:

dont forget to retorque the cover bolts periodicaly.
they can have a habit of compressing that gasket after several heat cycles,and then becoming loose.

BlackZ1R wrote: Three Bond works great, I use 1104. But I've never had to use it on a cam cover on my 1000.
Motor Head, good discussion using epoxy to fill low spots. we use JB weld and wax paper instead of the plastic zip lock baggie. good method, thanks for posting that on the board.
Kapa, did you check to make certain the bolts weren't bottoming out the last time you had the cover off? Patton may be on to something. Hope it stays dry for you.
Nothing worse than a pesky cam cover leak :pinch:

+100 I NEVER use silicone sealers unless you like leaks and silicone in your engine.
In theory, yes, no sealer on gasket, BUT it wont work everytime. If you were a service technician you wouldnt chance wasting another 1/2 hr sealing something you should have sealed before. Yamabond/KawasakiBond/HondaBond/ 1104/ all the same GREAT sealer even on no gasket mating surfaces. Light coat not too heavy. I also turn cam plugs 180 installed where flat side of cam plug faces cam, no way they can push out.Let totally dry before running motor. I also contact cleaner ALL surfaces to ensure perfect seal. Even if that cover is slightly warped, that sealer should fix it.

Motor Head wrote: Glad to hear its not leaking, but you shouldn't have to glue down the gasket, only a bit over the end plugs. But hey if it works, get out and ride it.

Yeah I hear ya but I've owned this bike for 10 months and this is the first time I've had the cam cover area leak free. Read through this post and you'll see what I've gone through. This bike will absolutely leak oil from the cam cover if the gasket is dry.

Regarding the threads, yes I did check to make sure the bolts weren't bottoming out.

I can enjoy this great bike now. I've been holding off on cleaning up the frame and repainting the bodywork until the leak was fixed.