Time To Pull The Head, What Else Am I Missing?

Well I've got a pretty good oil leak from the cylinder head gasket on my 82 KZ1000J ELR. The cylinder head is torqed down to spec, so it's time to replace the gasket. While I've got the head off, I had planned on replacing the pistons and rings. I haven't had any symptoms to lead me to believe the valves or valve guides need replacing. Should I replace them anyway? This will be the first time I've opened up this engine since I got her.

What else am I missing?

What about timing components or chain?

Top & base cylinder gaskets, valve cover gasket, possibly engine pre lube, don't know your motor but are there cylinder timing chain O-rings between cylinder and head....

Cylinder bolt crush washers...

Since removing exhaust, new copper exhaust crush washers...

Anti seize compound for your bolts once you start putting everything back together...

New oil and filter...

Hows your intake manifolds?

Hows your valve clearances (shims)?

New plugs...

Hmm, what else have I missed....

Why replace the pistons and rings? Sounds like your going for more than just a maintenance fix on her.

I regret not placing valve guides and seals on my last head removal but all depends on you mileage and abuse.

My motor is a mystery as it's a salvage bit, no telling ho many miles were on it before purchase.

kzr750r1 wrote:

Why replace the pistons and rings? Sounds like your going for more than just a maintenance fix on her.

I regret not placing valve guides and seals on my last head removal but all depends on you mileage and abuse.

My motor is a mystery as it's a salvage bit, no telling ho many miles were on it before purchase.

This motor is a mystery for me as well. Although to the best of my knowledge it has less than 6k on it, I don't believe the PO had ever opened her up. The cylinder head gasket that is leaking could very well be original and split and/or dried out. So without trying to turn this into a major project, while I have the head off, I want to take care of the pertinate stuff.

I'd say while your in there, to replace the valve stem seals and check the valve guides for wear.

My '77 KZ650C1 has over 48,000 miles without ever having the head pulled and there's no smoke or other signs that the rings need replacing. It's your bike, but if it was mine I wouldn't even think about rings & pistons or valves & guides at what may be 6,000 miles unless the bike was smoking and had poor compression. Replacing the head gasket represents a relatively low risk of causing a problem, but replacing pistons, valves, etc. when they're not needed introduces (in my opinion) unnecessary risk of creating a problem where there was none. Like the saying goes, don't fix something that ain't broke. That's a really great looking bike. Ed

650ed wrote:

...wouldn't even think about rings & pistons or valves & guides at what may be 6,000 miles unless the bike was smoking and had poor compression. Replacing the head gasket represents a relatively low risk of causing a problem, but replacing pistons, valves, etc. when they're not needed introduces (in my opinion) unnecessary risk of creating a problem where there was none. Like the saying goes, don't fix something that ain't broke. That's a really great looking bike. Ed

Amen! And please forgive a nagging feeling that it might not be a blown headgasket.

Would first confirm existance of a headgasket issue.
Assure valve clearances to specs and do compression test -- which cylinder is low?
Do leakdown test -- determine where compression is escaping.

To visually confirm source of leakage:
Clean engine and thoroughly dry.
Apply powdered foot spray deodorant all around head gasket, valve cover gasket, tach drive, exhaust clamps, exhaust clamp nuts, half-moon valve cover plugs.

Start engine and allow to idle while using a flashlight to closely examine the powered areas. Any leakage should readily appear.

Good Luck!

if your not going to replace the valves, at least polish them up a bit and lap all the valve seats. Maybe clean out the ports of carbon and such (without removing metal). I found a small die grinder with a cylindrical shape sandpaper bit worked great for cleaning up the valves and ports.

And if i got that far along i would replace the valve stem seals as well, that all goes along with checking the clearance when done.

I had the same problem on my bike, the head had never been off according to what was left of the gasket. It was old and practically gone!

If you pinpointed thats where the oil is coming from then it most likely needs a gasket.

Very sick bike though man, kinda looks like mine but twice the balls...hahah.

Good luck with it man.

MentalMike wrote:

Well I've got a pretty good oil leak from the cylinder head gasket on my 82 KZ1000J ELR. The cylinder head is torqed down to spec, so it's time to replace the gasket. While I've got the head off, I had planned on replacing the pistons and rings. I haven't had any symptoms to lead me to believe the valves or valve guides need replacing.

How many miles on it? I would think the pistons/rings would last a lot longer than valves. My 750 needed valves at 50k and again at 75k and the rings made it to 75k.

Definitely get the valves lapped and change the valve seals.

Some J motors had porous cylinder blocks that leaked oil. I replaced the block on one 82ELR for that reason.

Kawasaki had updated the pistons & rings for the 83 ELR.

Before you tear it down, I suggest the following.

1st - clean the motor thoroughly.
2nd - get a can of spray foot powder and spray the area you suspect is leaking. Lay down a nice thin coat of the spray on powder. In this case, I'd spray the block as well.

3rd - start the motor, bump the idle up to about 1800RPM and plug off the engine breather so it can build some crankcase pressure.

Watch the area that's suspected of leaking. In a minute or two, the sprayed on foot powder will turn brown where the oil leak is. You should be able to pinpoint the exact source of the leak this way.

I used that technique frequently to pinpoint leaks. When ridden, the oil spreads out and it's very hard to tell exactly where some of the leaks were. This method assures you will find the source.

Once you've done that, the next step is a leakdown test on all 4 cylnders. That will give you the health of the valves and rings. That in turn will tell you how far down to tear the motor.

If you end up pulling the head off, make sure to get it decked straight. If you pull the block as well, get it decked straight also.

The head should get a valve job with new Kawasaki OEM valve seals and if needed [I doubt it will with the mileage you're reporting] new guides.

Larry C

Fellas, thanks for all the responses.

I haven't pinpointed the leak using the foot powder method, but what I have done is cleaned the motor to nothing short of being spotless and watched as oil seeped from the gasket area just left of the #1 exhaust header and eventually sprayed all over my pants leg. I repeated this process after each ride, so I think I have a good idea where the leak is coming from.

I have done a compression test and all cylinders read between 145 to 150. I haven't performed a leak down test yet, but I will this week. If I get good results from that, then I guess I'll leave the pistons and rings alone and just concentrate on the valves and guides.

I'll update when I've made some progress.

MentalMike wrote:

Fellas, thanks for all the responses.

I haven't pinpointed the leak using the foot powder method, but what I have done is cleaned the motor to nothing short of being spotless and watched as oil seeped from the gasket area just left of the #1 exhaust header and eventually sprayed all over my pants leg. I repeated this process after each ride, so I think I have a good idea where the leak is coming from.

I have done a compression test and all cylinders read between 145 to 150. I haven't performed a leak down test yet, but I will this week. If I get good results from that, then I guess I'll leave the pistons and rings alone and just concentrate on the valves and guides.

I'll update when I've made some progress.

If not already done, would double-check tightness of both #1 exhaust clamp nuts. And be positive the copper crush gasket is completely sealing.

Equal compression in all cylinders mitigates against leaking head gasket in #1 where it's psi is the same as the others not suspected of leaking.

Btw, was the bike previously leak-free during your ownership, with the leakage appearing out of the blue? Or was any engine maintenance work, such as exhaust removal and replacement incident to oil and filter change, performed before the leakage occurred?

During the leakdown test, should be able to hear compression loss escaping from the blown gasket area. And perhaps see emerging oil seepage from wherever. Objective being to confirm diagnosis of leakage source through blown headgasket or elsewhere.

A stethoscope would be useful, but shouldn't really be necessary.

Good Luck!