Head Gasket Question(s)

Pre-emptive strike first, yes I did a search. My question concerns head gasket selection and the best process for installation. I have opted to install a Cometic one-piece head gasket on my 1977 KZ-1000. My theory for choosing the Cometic gasket is that it is a one piece design with no middle o-ring. It stands to reason that there are fewer areas to leak oil with a one-piece gasket versus an OEM style 3 piece gasket at least that's my thought process right now. For those of you that have used the Cometic one-piece gasket do you have any suggestions for the installation process? As I understand it, I will have to fill the o-ring grove with some type of sealer and should actually apply the sealer so it sits above the deck surface of the cylinder block. Should I put any sealer on top of the head gasket where it comes in contact with the o-ring area on the head? Should I coat the Cometic gasket with anything before I install it and does it make a difference which way the gasket is installed? Finally, once the engine is buttoned up it was suggested by someone to start the engine and let it come up to operating temperature then shut it off, let it cool down to ambient temperature and re-torque the head. Do you go through the process once or should it be done multiple time to make sure the head is properly torqued. As an information point, I intend to install the valve cover gasket dry and perhaps use just a little bit of RTV sealer on the cam shaft end caps. Thanks for any information on the matter. I would have thought there would have been some install instructions with the Cometic gasket, but none were provided.

Rick H.

No eBay APP ID and/or Cert ID defined in Kunena configurationFill the camchain 'o' ring groove proud with RTV .
I use this VTECH - .
Leave it overnight to cure then slice flush with the block with a sharp box cutter blade.
You can also apply a small amount fore and aft of the camchain tunnel but nowhere else as this area gets hammered with oil spray from the chain..
Once built , Run the engine , get it hot and allow to cool overnight and re-torque.
Re-torque - COLD - after 500 miles if needed.

Great advise from Zed. Follow his steps carefully. It appears that on my engine, a 77- KZ-1000A,(1327 kit). That the head gasket was coated with red RTZ on both sides prior to assembly, but I am not able to confirm that with the builder as it was 30+ yr's ago, but you can visually still see the red RTV. I hope you get more info and have a solid build....

I've tried the RTV method both ways. Cutting it flush after it cured and assembling it while it's wet. It still weeped. This last time I filled the groove with 20 min JB Weld then used copper silicon around the cam chain tunnel. It worked great. I got some APE head studs and reused the one piece head gasket in the same way. I also used copper spray on the gasked being it was used and it doesn't leak. I did develop a base gasket leak and slowed it down by retorquing. I have to go back in there to replace the valve guide seals and new rings. I reused the rings last time around. This time will be new rings, viton guide seals, Cometic head gasket and new base gasket. I got the seals and new cam cover gasket I'll put on tomorrow when I adjust the valves. I soak the cover gasket in fresh oil so I can reuse it time and time again. I smear a little copper silicon on the end plug areas top and bottom. Not a lot, just enough to make it tacky.
Steve

I have always used a two piece head gasket with a O.E.M. only center o-ring on all of my motors. Never had one leak, even after two or three years down the road. Never used anything but O.E.M. head gaskets too!!! If it was a fiber style O.E.M. head gasket, I would brush on a coat of K&W Coppercoat. On my center o-rings I coated them with Three Bond TB-1211. On my 1075cc or 1103cc motors I used the '83/84 GPz1100 multi-layed steel O.E.M. head gasket. Put them on dry except right around the four outer studs I put a thin layer of TB-1211 on both sides of gasket. I first torqued head to 18 foot pounds then to 30 foot pounds. I never used more than 30 foot pounds of torque at anytime. All of my motors I used MTC Golden studs. only. Never fired motor up until they sat for 24 hours to let the TB-1211 set up.

Retorque!! I never loosen nuts. I just hit them with the torque wrench. If they moved, they moved. If the torque wrench clicked that was good enough for me!!! I checked them after a few hours of running and that was it until the next teardown. The only motor I ever had any type of oil leak on was my Kz1000J model based S1. I had two base gaskets that ended up weeping after a few hours of running time. And that was with O.E.M. base gaskets the ones you had to almost chisel off to remove them!!!!!!

That early model valve cover gasket can be used a few times before having to replace it. I always put them on dry too. The cam plugs just a thin coat of silicone on the bottom of each cam plug. I always put my cam plugs in backwards with that lip on the inside of head. That way gives you a bit more protection of them working their way out of place.

TB-1211 applied to center o-ring before assembly.


O.E.M. Kawasaki cam plugs installed backwards.

More solid advise and good stuff. Also, I would never loosen my nuts prior to retorquing . That could lead to a weeping scenario that no nuts, or head, should be subject to

Thanks for the suggestions everyone. I find it fascinating as to how many different approaches there are to install Kawasaki 900/1000 cc head gaskets. Many different methods to try and get to the same result being no leaks. Clearly there is no one "right" way to do this. The fan base also seems split of the use of a one piece or two piece gasket which surprises me in a way. In the past I have used Copper Coat on most of the head gaskets I have installed, but I am not so sure on this one. It would seem to me the best cure would be for a head gasket company to make a one piece gasket for this engine with an embedded cam chain tunnel o-ring. Decisions, decisions.....

Rick H.

I wouldn't use copper coat on a new gasket. They have sealant built in. I only used it on old gaskets I had to reuse. I've also used silver spray paint on them which was common back in the day. I did that when I put in viton valve guide seals in 14 and reused the one piece Z1 gasket I had on it. In 13 When I put it together after sitting 15 years I bought a complete aftermarket gasket kit. It came with the large O ring that failed the first year. It had a split in it and I'm sure a OEM O ring would have been better but in this case being the valve guide seals were leaking letting hot exhaust gasses into the head I doubt it would have last. In the past the OEM O ring would last 2-3 years. I even reused the O ring in the 80's after slathering it with copper silicon when I installed the almost new Z2 valves I took out of a junk head I had on hand. Being out here in the "Boonies" and with little money I had and still have to be creative. I am a firm believer in the one piece head gasket system. I'm using a Z1 head gasket I bought years ago i had hanging in the shed. This time around It will be all new with the KZ1000 head I'm restoring. The head I have on it now is worn out with a hairline crack in one seat, sloppy guides, had to "tip" the exhaust valves and the lifter bores may be worn out as well. Larry suggested he could replace the seat but when I asked him how much it would cost I got no answer so I decided a different head was the answer. Hopefully this time around it will last and I can RIDE THE PISS OUT OF IT for a few years. That is unless I get a 1105 kit then I'll start all over again.
Steve

I really am impressed by your enthusiasm Steve! Here I am trying to avoid doing more work than necessary and you just seem to dive right in and go for it. I have been resisting taking the cylinder block off my bike so as not to upset the base gasket and worry about re-installing the pistons, but maybe I should follow your lead and jump in the pool. I am relatively sure based on measurements that the cylinders are within spec and felt it was pointless to replace the piston rings, but I may have to rethink that approach. My thought was to just put the head back on and see how it runs, but I may alter that idea. Thanks...

Rick H.

DO NOT put any sealant on the new COMETIC graphite head gasket except where stated in my previous post.
That IS the right way to do it.
If using new MLS then the same goes for that also as it has sealant already on the surface.
Spray on sealants such as Loctite 3020 should only be used on copper gaskets and plain rubber, paper, cork and metal gaskets.
Re-using old gaskets with different methods of attempting to obtain a seal is down to the individual owner.

Copy what you said Zed1015. What do you mean by "MLS"? So the ENTIRE o-ring grove should be filled with the sealant correct? Including the passage ways to the cam chain tunnel?

Rick H.

Rick H. wrote:
Copy what you said Zed1015. What do you mean by "MLS"?

(M)ulti (L)ayer (S)teel head gasket like Dr. Gamma´s pic shown.