cam chain cavity seal

[petejw]

Hey all,

Ive just picked up a supposely complete gasket set non genuin,
reading the clymers it states after putting the head gasket on the motor, a cam chain cavity seal is suppose to go on next,
when i pulled my head off, there was no cavity seal, and no cavity seal came with the kit.
my question is, is my model bike suppose to have this??
1981 RH.

also are the carb holders suppose to have gaskets between them and the motor, again no gaskets were supplied for this.

thanx in advance

pete

[DiverRay]

Pete;
You must have an old book. Yamaha quit using this seal, and if you try to put one in, you will probaly crack the head. I'm not sure about the seals for the carbs.
Ray

[TopCatGr58]

Hey Pete,

Yamaha used the cavity seals in the early years, but dropped them later, so, no, your 81 doesn't have nor need one.

The carb holders are supposed to have rubber OVER the metal parts where they mate up to the head. Has been suggested by Yamaha Mech, and others to use YAMABOND sealer, and or even a gasket, but sealer just on the intakes would be enough. I used permatex #2 sealant on my old intakes, after removing the dried, crumbling rubber from the mating surface! Has been recommended NOT to use RTV due to silicone and gasoline doesn't mix well!

Of course, I'm not an ACTUAL Mechanic as has been revealed in John's recent MECHANIC's POLL!
T.C.

[prometheus578]

Probably??

Yamaha quit using this seal, and if you try to put one in, you will probaly crack the head

Probably? Make that definately! Right in front... above the cam chain tensioner. JBWeld and silicone will hold it back on for a few years, but then she'll start to leak.
The above statement in no way means that I was stupid enough to do this. I just happened to umm... err... read about it somewhere.

[petejw]

Thanx again 4 the replys,
I didnt think that there was anything that was suppose
to go there, just wanted to b sure.
Ive cut my own gaskets 4 the carbies as there was
very little rubber left.

peter