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1983 R80 G/S Cylinder Gasket?

armartel

New member
I'm replacing the gaskets on the cylinders and the push rod seals, etc. I ordered all the parts and noticed in my Clymers' manual that there a gasket at the connection point of the engine block and the cylinder head in the manual (in addition to the rubber gasket)? I don't, however, see it on the Fiche.

Picture attached and the paper gasket I’m looking for should fit between the cylinder head and the engine block. Anyone know if this is a mistake in Clymers or if Fiche just doesn't show it? P.png
 
No paper gasket, just the large cylinder o-ring and the two cylinder stud o-rings. Many of Clymer’s pictures are not year or model specific. Your bike is only 8.2 compression ratio, too, so no need for cylinder spacer plates and such. You WILL want to have a very thin coat of sealant, like Permatex gray, on the cylinder-to-block mating surface—don’t let it get into the area of the cylinder stud o-rings.

Best,
DG
 
First, I wouldn't trust Clymers in this instance. As for the fiche, that's closer to reality. Any paper or metal gaskets were done away with probably by the /6 series. I know metal gaskets were used on the /2 and early /5 bikes. The R60/5/6/7 bikes have a separate metal gasket that can be used as a compression reducer. But for '83, I suspect it's only the large o-ring...plus a judicious layer of sealant like Permatex Ultra Grey, Hylomar, DreiBond, YamaBond, etc.
 
Some of the older air heads had a base gasket. Yours doesn't. You have a large "O" ring around the base of the cylinder and two smaller ones that go on the two top studs, at the base of the cylinder. Use grey Permatex to seal the base of the cylinder as you install it. Also when replacing the pushrod seals, put a little grey Permatex on the outer surface of the seal where it goes into the engine block. Good luck with your project.
 
What you see in the Microfiche is correct. If you need part numbers or an up to date fiche, Max BMW website has one you can look up parts on. They also have the parts in stock. St.
 
Some of the older air heads had a base gasket. Yours doesn't. You have a large "O" ring around the base of the cylinder and two smaller ones that go on the two top studs, at the base of the cylinder. Use grey Permatex to seal the base of the cylinder as you install it. Also when replacing the pushrod seals, put a little grey Permatex on the outer surface of the seal where it goes into the engine block. Good luck with your project.

This is all good except that you never put Permatex, Silicone or any sealant on the push tube rubbers. They need to move a bit as things expand and contract. When installing them I use Red Rubber Grease on them to help them slide into place and conform more easily to the space they sit in. It also preserves rubber and keeps it supple. Oak recommends a bit of engine oil for this but since oil is a petroleum product that breaks down rubber slowly I respectfully disagree with Oak on that one.

I've done three bikes this year this way and none of them leak from the push tube seals. Never used any sealant on them and never will.
 
This is all good except that you never put Permatex, Silicone or any sealant on the push tube rubbers. They need to move a bit as things expand and contract. When installing them I use Red Rubber Grease on them to help them slide into place and conform more easily to the space they sit in. It also preserves rubber and keeps it supple. Oak recommends a bit of engine oil for this but since oil is a petroleum product that breaks down rubber slowly I respectfully disagree with Oak on that one.

I've done three bikes this year this way and none of them leak from the push tube seals. Never used any sealant on them and never will.

This is a dynamic connection. Parts move. These seals need to not stick on the tubes. If they stick as the engine cylinders expand the seals lose compression against the block and leak. As stated, sealant is a no-no.
 
My bike has an 81 g/s motor, I just had the cylinders off two days ago, it has o-rings, no gasket.
I didn't put any sealant on anything so I guess I'll see what happens, it'll only cost me some o-rings and snap rings if it starts leaking.
It's my understanding that some type of cylinder base gasket could be used to lower compression but that's only needed in areas with low quality fuel.
 
My bike has an 81 g/s motor, I just had the cylinders off two days ago, it has o-rings, no gasket.
I didn't put any sealant on anything so I guess I'll see what happens, it'll only cost me some o-rings and snap rings if it starts leaking.
It's my understanding that some type of cylinder base gasket could be used to lower compression but that's only needed in areas with low quality fuel.

Is there a question in here somewhere??? :scratch

Friedle
 
My bike has an 81 g/s motor, I just had the cylinders off two days ago, it has o-rings, no gasket.
I didn't put any sealant on anything so I guess I'll see what happens, it'll only cost me some o-rings and snap rings if it starts leaking.
It's my understanding that some type of cylinder base gasket could be used to lower compression but that's only needed in areas with low quality fuel.

Well I've got the same motor, so it seemed helpful to share what was in there.
In about a week I'll have enough hours on it to report if sealant seems necessary, I'm betting on not since there wasn't any when I took it apart.
Too late for questions as I've already reassembled it!
 
Bone dry for 300 miles so far on mine, I think I read that Hylomar could be used on the pushrod seals but the o-rings should just be oiled during installation.
I didn't have any Hylomar, I did put some dielectric silicone grease on the seals, the o-rings just got a bit of oil.
I figured it's best to use nothing and just attempt to assemble it as originally installed, maybe I'd use something if I were working on someone else's bike to give it some extra certainty.
 
Bone dry for 300 miles so far on mine, I think I read that Hylomar could be used on the pushrod seals but the o-rings should just be oiled during installation.
I didn't have any Hylomar, I did put some dielectric silicone grease on the seals, the o-rings just got a bit of oil.
I figured it's best to use nothing and just attempt to assemble it as originally installed, maybe I'd use something if I were working on someone else's bike to give it some extra certainty.

Any attempt to use sealant on push rod tube seals is doomed to almost immediate failure. The seals must expand and contract as the engine heats and the cylinders elongate. The primary cause of leakage here is the seals sticking on the tubes. Oil inside the seal against the tube is necessary.
 
I believe the preferred sealant for the cylinder o-ring is Hylomar.

According to Oak's Top End Manual there is no sealant used on any of the three o-rings. He recommends oiling the large sealing o-rings with some oil just before you install them so they swell after installation. Same for the smaller o-rings.

He does recommend Hylomar for the base to cylinder sealing interface which is metal to metal. I used Permatex Ultra Gray in the last 3 top end jobs I have done in the past year and none of them are leaking. It seems to be ideal for this application and allows a bit more set up time which can be helpful.
 
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