With a thick layer of RTV, you can split the seal with added pressure
because that stuff has little tolerance for cru****ng - it splits and
crumbles. I find that a thin coat over cork will take the re-torque (as
long as it's not ridiculous) as the RTV is more of a gap filler/adhesive
than an actual gasket and the combo acts more like plain cork than RTV. I
use the film-over-cork as much for the release properties on removal as
for
the seal properties. That immediate second (and even third) torque round
you use is a key part of getting an even seat - even the metal covers have
a lot of warp over that long span.
Mike Romain wrote:
> I don't understand why folks would go and break the seal the RTV made by
> 're-torquing' the bolts after it has set.
>
> When the oil hits the gasket after the RTV has set, it expands the cork.
> This has the effect of 're-torquing' the bolts.
>
> On plain cork gaskets, a re-torque can be needed sometimes, but if you
> have to do this on a RTV seal, the seal has failed and you are trying to
> do a compression seal.
>
> Now I 'do' do a second torque pattern tighten after the first one
> because the center spiral set usually loosens when the ends get torqued.
> This is immediately though.
>
> Mike
>
> RoyJ wrote:
>> What Mike says but I do them without the cork.
>>
>> I'll add a couple of reminders. When Mike says clean, that means REALLY
>> clean. The RTV is not compatible with any sort of grease film. I clean
>> my valve covers in a 5 gallon bucket full of extremely hot water and
>> laundry soap. Top of the engine needs to be scraped, wiped with
solvent,
>> then hit with brake cleaner, wipe with paper towel. If the paper has
any
>> discoloration, clean it some more.
>>
>> Apply Permatex Black with or without the gasket (your choice), set the
>> cover on immediately. Open time on the Permatex Black is only about 5
>> minutes so you need to move briskly. Tighten the bolts down snug enough
>> to make sure all the RTV is contacting the opposite surface. Let it
cure
>> for 24 hours, spray it with water if you want to push it a bit. Torque
>> to spec after the 24 hours is up.
>>
>> Greg wrote:
>>> So after an hour on google, what is everyones recomendation on doing
>>> the valve cover gasket on a CJ7 258 engine, cork, rubber? RTV or not?
>>> Torque specs?
>>> Installed a rebuilt engine 2 years ago, new gasket leaked a small
>>> amount from start, so seeing that engine is sitting in new frame with
>>> no body around it, nows the time for a replace. So if anyone has any
>>> opinion or knows the torque spec I would appreciate it, aluminum cover
>>> by the way.
>>>
--
Will Honea
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