Valve cover gasket mating surfaces

serfrock wrote: Dr. G: Awesome - any idea what grit your honing stone is? I realize that you bought it some time ago, so no worries if not! Otherwise, anything in particular to look for when selecting an appropriate honing stone?

Its super fine. Guessing I would say 400 or 600 grit. I use it just for gasket surfaces.

I think I got it at a hardware store next to the hunting knives or the Snappy Tom man.

I use a Xacto number 1 handle with number 11 blades to scrape valve cover gaskets.

Instead of buying all the fancy gasket remover, just go buy some paint stripper, its the same stuff!!!

Just make sure its got methylene chloride in it. Just DO NOT get it on any painted surface!!!

I hope our worthless government hasn't ban that too!!!

650ed wrote: Remember - when you install the new gasket do not use sealer. Just put it on dry and you won't have that problem in the future. Ed

I did put it on dry, except over the cam end plugs and just past their ends a touch. Just like where I could see sealant had been before on my cover. You can also see the sealant in the service manual pics on the valve adjusting section.

Didn't seal up for me except where the sealant is. It actually looks like its wicking thru the gasket and not going under or above it. Can't be sure however, but it is an aftermarket gasket. It took about 3-4 times to get the torque on the bolts to stay put, after riding the bolts would be loose again as the new gasket was squishing.

I am considering putting the original gasket back on and seeing it if leaks. The only place it leaked before was around the cam end plugs, now that's the only pace it does not leak. Go figure. :S

Interesting; I wonder if the aftermarket gasket material is at fault? My KZ650 manual does not call for sealant and the bike didn't have sealant on it from the factory (I bought the bike new). I use Kawasaki gaskets and put them on dry and have never had any leakage. The other nice thing about dry is that you can use a gasket many times without damaging it if you're careful removing the cover. I've wrecked a gasket once or twice over the years through carelessness - ooops.

Here's my view on using sealant; others may disagree. If the idea of putting sealant on a gasket is to prevent a leak, please consider the following. Let's say you have two metal surfaces, i.e. a cylinder head and a valve cover, and there's a gasket that goes between the two. The purpose of the gasket is to prevent oil from leaking between the two metal components. So let's say you put the gasket in there dry (no sealant at all) and bolt the cover to the head squeezing the gasket between the two. Now consider if you could see that cover/gasket/head joint from inside the engine. You would see metal (the head), the inner edge of the gasket, and metal (the valve cover). Now you splash plenty of oil inside that area so the joint is soaked in it. Now looking from inside the engine you see oily metal (head), the oily inner edge of the gasket, and oily metal (the valve cover). If the oil is going to seep between the metal and the gasket will the oil care if it seeps between the head and the gasket or the valve cover and the gasket? No; if it is going to leak it can leak on the head side OR the valve cover side of the gasket. So, IF the only way to prevent a leak was to put sealant on the gasket you would need to put it on both sides. Fortunately, the dry gasket will not leak on either side, so no sealant is needed. This assumes no one has gouged the metal mating surfaces when trying to remove a gasket that some previous owner has glued on because they didn't know sealant was not needed. In that case sealant may be needed but only on the gouged area.
This brings up another point; in the Kawasaki service manual there are a FEW areas where sealant is called for. The best example I can give is a spot on the KZ650 clutch cover gasket. The manual calls for about 1 inch of sealant on a spot on the engine side of the clutch cover gasket where the gasket covers a joint between the lower and upper engine castings. This is required because mating surface has a seam at this engine casing joint which the gasket alone may not seal. This may not be obvious to someone doing this job the first time. Ed

I have a feeling its the aftermarket gasket causing the leaking. I cannot know for sure if the gasket I took off was the original....but....its a different material than the aftermarket one and it came off clean with only sealant on the ends over the cam end plugs. The 1977 KZ1000 manual calls for sealant on the cam end plugs. It says....

Replace the cylinder head rubber plugs with new ones, applying a liquid gasket to both ends of each rubber plugs before installation.

Kinda vague, I guess they mean the upper corners of the plugs. I did that and ran a tiny bead across the top of them and past them just a touch. I did that based on the pics on pg. 15 in the valve clearance section. There are two photos (B10, B11) that clearly show old sealant across the top of the cam end plugs.

Mine looked JUST like the photo when I took my valve cover off. Hard to believe the cover had never been off but maybe it hadn't? Or is was only done by a dealer who knew what they were doing. The old sealant was a crusty brown stuff that flaked right off the head very easily. I can take a photo of the valve cover gasket I removed, I believe it still has sealant on it in those locations too. I want to try to reuse that gasket since the aftermarket one on there now is leaking. If the the old sealant comes off easily it should be ok to use.

I know the 650 cam end plugs are a very different design with a pin thru them right? I've heard talk of the 1000 plugs coming out, something I don't think is possible with the 650. Maybe that sealant is as much for holding the plugs in place as anything else.

Wasn't the 650 designed after lessons learned from the 900/1000?

Yes; the KZ650 plugs are held in place by cam cover screws running through them; they can't pop out. It's not a bad idea to put some sealant on the semi-circle part of the plug where it mates with the cylinder head, but I've never used any sealant that would come in contact with the cam cover gasket and have had no leaks. Ed

serfrock wrote: Thanks, Ed! I actually have some of the Permatex stuff, but found it to be of little use. I may have been too sparing with it for fear of it getting into the engine. Is there any risk there?

And thank you, baldy. Emery cloth sounds like it would be good, but is there any risk of the grit getting inside and damaging the engine?

Maybe I'm being paranoid -- just trying to be a more careful mechanic than my bike's previous owner!

Go buy can of 3M Brake Cleaner and put a little on a shop towel...it will take the residue right off. I buy it by the case and we use it all the time.