head assembly...rocker stud oring/rubber gasket needed?

[surfbug1]

the rocker stud, I heard it takes and oring.....

but in the haynes manual it shows a rubber gasket like what is on the oil coller....

why is this gasket/oring needed?

which one is it?


thanks

al

surfbug

[CHAZAVW]

the rocker stud, I heard it takes and oring.....

but in the haynes manual it shows a rubber gasket like what is on the oil coller....

why is this gasket/oring needed?

which one is it?


thanks

al

surfbug

on the rocker.... there is a black o-ring.....

on the oil cooler adapter there is red or green oil seal.....

[turboblue]

If your rocker stud holes are a through hole, then yes you need them. Black O-rings about an 1/8" cross section, 1/2" or so on the OD. On some cylinder heads, these tapped holes are a blind hole. No O-ring necessary.

[Glenn]

All the gasket kits i've bought come with the o-rings.

[Marc]

Early (40HP-style) heads used a wedding-band-looking seal, late heads used either a thin O-ring or no seal. It's pretty obvious what's needed by looking at the depth of the recess around the stud; the no-seal type have a small chamfer but it isn't big enough for the O-ring to sit in.

[surfbug1]

I will use the black orings that came with the kit.

they are as described by

"""Black O-rings about an 1/8" cross section, 1/2" or so on the OD."""

What actually do these o-rings do, and why are they required?


they look like they are just for vibration control.........of the rocker arm assembly.....right?


al

surfbug

[turboblue]

I explained the reason for them in an earlier post. If you have through holes for your rocker stand studs, you need to use them. If you have blind holes you don't. I'm talking about where the actual rocker stand stud screws into the head. It either pokes out the back or it doesn't.
The o-ring keeps oil from wicking past the threads and causing a leak.

[Xoloski]

Do you have an actual size of the O-rings?
I know you said .125 cross section x .500 OD but have you actually measured the O-ring?
Also, I would think the O-ring would be metric, not SAE.

Not trying to pick a knit, but I don't want to buy a whole gasket set, just the O-rings and the nearest parts store where I will be going in Alaska is a considerable distance.

[Xoloski]

The actual size of this o-ring is 2.5mm cross section diameter x 13mm OD.
The SAE approximation above was very close.