Valve cover seal - Use RTV or not?

[FJmonkey]

I cleaned the valve cover and found that the last mechanic that checked/adjusted my valves used a silicone or RTV sealant (clear) to seal the top portion of the rubber gasket to the cover. Is this normal, advised, or a bad idea? I cleaned it all off since pieces were coming off and I could not keep them out of the valves otherwise. I am just not sure if I should reseal it with High Temp RTV when reinstalling. The seal was replaced about 2 or 3 adjustments ago and still looks and feels like new. My first impression is this seal is not intended to be used with additional sealant, unless leaks require it when a new seal cannot be obtained.

By the way, anyone have a 275 shim they can swap? TRoy has the other shims I need and is sending them along to me. I just need one more to complete the job and ride again.

Randy, whats your price on shims?

[Ratchet_72]

You might wanna check the rubber grommets that seal the valve cover bolts to the cover before you button everything back together.  You can use rtv on most motors so what's the harm with the fj? Just don't go crazy with the stuff. Do not over-tighten the cover bolts. Things break and it won't help the seal anyway.

[rktmanfj]

+1 on the cover bolt grommets, and do not overtighten the screws.

I don't think that any kind of sealer is needed for the cover gasket, but it's tough to get it to stay in place while putting the cover on, so I used just enough Yamabond in the groove at intervals, to hold it in.

Randy T
Indy

[FJmonkey]

Thank you both for the input. I will use just a dab to keep the seal stuck to the cover and make sure it fully cures, clamped to a flat surface to assure it mates properly to the heads before assembly. The bolt grommet seals were changed at the same time and they looked clean (not leaking) when I removed them. I think I have a good seal as is. I will verify proper torque on the bolts to prevent cracking the covers. Thanks again, I love the support from the group. 

[ddlewis]

Definitely be careful tightening those valve cover bolts.  they are shouldered and the shoulder will meet up with the top of the cam journal and will twist right off unbelievably easy.   DAMHIK!

[FJmonkey]

DDLewis, are you speaking from experience?.....Sounds like it. Thank you for the advice. I have busted many things in my wrenching and would gladly spare others from my grief. A heart felt thanks.

[RichBaker]

It is not a good idea to use RTV on any engine.... it can get into the oil galleries when the pieces start coming off and clog things up and cause all kinds of grief. Just not a good idea and it really isn't needed in this application, anyways.... the cam cover gasket has no need for RTV. I've never used it on my FJ and she doesn't miss it....

[threejagsteve]

I'd agree that RTV is probably not a good idea as a general rule (unless an emergency dictates otherwise) but I've used a thin film of Permatex Form-a-Gasket # 2 (different composition, but a similar result) for years to hold gaskets in place while assembling and never had a problem I could blame on it. But do note the key words: "thin film".

Cheers,
threejagsteve
(my "other" hobby is '60s Jaguars )

[FJmonkey]

Thanks again to all the advice. I did use the RTV but not enough to squish out the sides ( a very small bead in the groove). It is simply holding the gasket in place. With no RTV sticking out, there should be no issues with pieces coming off and fouling the oil ports. I will let you know during my next valve check how it held up.