Re: Intake Gasket Failure Question

In article <bXW3e.892058$8l.44957@[EMAIL PROTECTED]
>, 
violet_lightening_modified@[EMAIL PROTECTED]
 says...
> nospam.clare.nce@[EMAIL PROTECTED]
 wrote:
> 
> > How can you blame it on the technicians or poor preparation on a
> > factory new engine? It is GM's fault - pure and simple. A design that
> > uses low clamping loads combined with gasket materials that cannot
> > seal under low clamp load conditions is poor design, no ifs, ands, or
> > buts about it.
> 
> I was talking about the RTV section of the gasket.  Eventually
> they all do leak, but I and other techs that I know that take the
> time to use RTV properly don't see the intake gasket back leaking
> from the RTV very often.  But the one's that dont take care, usually
> are re-doing them.
> 
> The entire engine design is suspect....but you are right, bean counters
> will do us in.
> 
> Ian 

After cleaning the surfaces real good I use McKanica red High Temp RTV 
around the corners of the intake as well as round the coolant passages 
on the gasket. With some thread locker and that McKanica RTV there are 
no repeat leaks. Great stuff!

In article <blX3e.403$l13.202@[EMAIL PROTECTED]
>, pnsman64@[EMAIL PROTECTED]
 says...
> I am a member of this club, 98 Lumina 3.1 once when it was under
warranty 
> and now again at almost 80k!  I plan on replacing the coolant fluid with
the 
> good old fa****on Prestone green antifreeze.  Does anyone think all this 
> trouble may be from the new dex coolant or just crappy design?

In my experiance Dexcool is still far better if the leaks are repaired 
correctly. When I remove plastic gaskets that have been running 
conventional green coolant I find most of the plastic material is 
missing and whats left of the gasket is very brittle. I also find a lot 
of pock marks in the aluminum which will never re-seal without good RTV. 
However the rubber beads built into those gaskets are usually swelled up 
which is the "only" advantage the silicon based coolants give you. 
(until they blow out from lack of plastic material)

Dexcool contains a plasticizer which softens up the plastic gaskets ever 
so slightly. For the 60deg motors this is a huge problem considering 
they dont have a very good clamping load on the gaskets and the gaskets 
are taller and thinner around the passages. For the 3800's lower intake 
gaskets this isnt much of an issue.