Is there a hi-temp expanding foam on the market?
Fred Mann
I have a small hole in the exhaust manifold right where it attaches to the
engine -- actually a small piece of the gasket is missing. There's a little
space in there that would seem ideally suited to accept a dollop of foam.
The foaming insulation at the hardware store can only deal with temps below
200 degrees. Is there anything out there with a higher temp rating?
(JB Weld works okay, but doesn't seem to last)
Thanks!!!!
Fred
Brent P
Anything but replacing the gasket will be short-term.
dave AKA vwdoc1
"Brent P" <tetraethylle...@yahoo.com> wrote in message
news:RdOdndNqR6DKK77V...@comcast.com...
cuh...@webtv.net
cuhulin
N8N
wrote:
What Brent said. If the manifold is warped it should be surfaced, or
if you're chea^H^H^H^Hfrugal I have heard of people using fine solid
copper wire to "o-ring" the gaskets.
nate
Scott Dorsey
>I have a small hole in the exhaust manifold right where it attaches to the
>engine -- actually a small piece of the gasket is missing. There's a little
>space in there that would seem ideally suited to accept a dollop of foam.
>The foaming insulation at the hardware store can only deal with temps below
>200 degrees. Is there anything out there with a higher temp rating?
No. A foam would not work well over a wide temperature range, because the
gas inside the bubbles would expand and contract a lot.
You might consider red RTV, but really the solution is to replace the gasket
and do it right.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Fred Mann
undertaking to do it right. Not worth it to me.
I may try the red RTV though. Thanks!
Scott Dorsey
If it's severely rusted, any filler you put on is going to adhere only
to the rust, not to the metal underneath. And the rust is not a solid
substrate and will not hold it on very well.
That is part of why the JB Weld is not working.
N8N
Start soaking the hardware with penetrating oil now (NOT WD-40) and
invest in a MAPP torch (or oxyacetylene, if you think you might be
doing this a lot.) also some 6 point sockets and bolt-outs if you
don't have them.
Is the manifold held on by studs or bolts? If studs, run a die down
the threads before you try to remove the nuts. Use the die
"backwards" so it cleans the threads right down to the nuts. If the
mfgr. of your vehicle was throughtful, they used copper or brass nuts
which will burn right off with a hot enough torch without damaging the
studs.
nate
Kevin
@bignews3.bellsouth.net:
> Unfortunately, everything is so rusted that it would be a massive
> undertaking to do it right. Not worth it to me.
> I may try the red RTV though. Thanks!
>
>
the only way anything will hold is to get it into the crack. JB weld
will be your best bet, if you can get a vaccume in the exaust using a
vacume cleaner or better a vaccume pump and pull the stuff into the
crack using the internal vaccume. anything else is a waste of time.
(other than the correct fix of course.) KB
--
THUNDERSNAKE #9
Protect your rights or "Lose" them
The 2nd Admendment guarantees the others
jim
Furnace cement ought to work. Get it from a place that sells wood stoves. Follow
the instructions for filling cracks. Give it a full day to dry. You have to make
sure you get all the moisture out before you get the temp above boiling or it
will crack.
-jim.
----== Posted via Pronews.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.pronews.com The #1 Newsgroup Service in the World! >100,000 Newsgroups
---= - Total Privacy via Encryption =---
none2u
"jim" <".sjedgingN0sp"@m...@mwt.net> wrote in message
news:1210378750_1932@isp.n...
>
>
> Fred Mann wrote:
>>
>> Unfortunately, everything is so rusted that it would be a massive
>> undertaking to do it right. Not worth it to me.
>> I may try the red RTV though. Thanks!
>
>
> Furnace cement ought to work. Get it from a place that sells wood stoves.
> Follow
> the instructions for filling cracks. Give it a full day to dry. You have
> to make
> sure you get all the moisture out before you get the temp above boiling or
> it
> will crack.
>
> -jim.
>
>
>the heat. He has to live with it or replace the gasket or manifold.If its
>warped too much.
Nate Nagel
I just noticed that this was posted to the VW group - what kind of car
are we talking about here? This might be the excuse you need to swap to
a dual outlet manifold/downpipe combo if it's an A1 :)
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
jim
none2u wrote:
>
> "jim" <".sjedgingN0sp"@m...@mwt.net> wrote in message
> news:1210378750_1932@isp.n...
> >
> >
> > Fred Mann wrote:
> >>
> >> Unfortunately, everything is so rusted that it would be a massive
> >> undertaking to do it right. Not worth it to me.
> >> I may try the red RTV though. Thanks!
> >
> >
> > Furnace cement ought to work. Get it from a place that sells wood stoves.
> > Follow
> > the instructions for filling cracks. Give it a full day to dry. You have
> > to make
> > sure you get all the moisture out before you get the temp above boiling or
> > it
> > will crack.
> >
> > -jim.
> >
>It wont work either. Been there done that. It wont take the gas pressure or
>the heat.
Yes I hesitated to offer the advice because it probably won't work if not
done correctly. Furnace cement will definitely take the heat - a lot more
heat than a car exhaust usually gets. And it expands at the same rate as
iron so heat and expansion aren't a problem even if you get the exhaust
cherry red.
It won't work on tin exhaust parts that flex but for filling a crack
where it is rigid and there is no flex it shouldn't be a problem. Of
course there is a bit of skill to applying it correctly so that it adheres
and locks itself in. It won't work on furnaces and stoves either when not
applied correctly.
-jim
>He has to live with it or replace the gasket or manifold.If its
>>warped too much.
Fred Mann
"jim" <"sjedgingN0sp"@m...@mwt.net> wrote in message
news:1210461952_1998@isp.n...
I think I'll try this next ... if there is a "next" . I JB welded it a few
days ago ... maybe it will hold more than a few months. I don't drive that
much.
And by the way, the car is a 1983 VW Rabbit GTI. And the rust problem is
limited to the nuts and bolts - the manifold seems to be fine. The nuts are
starting to look like something off of an excavated sea wreck. I don't think
I have the tools or patience to do it right.
Thanks again for all of the help!!!
dave AKA vwdoc1
Sears sells some "rounded-nut" sockets that should work for you.
If you remove the intake manifold, that should give you more room to do it
above the engine. ;-)
Some shops can do this for you and they won't charge that much.
I personally like the studs replaced if they are too horrible. And install
new brass self-locking nuts. <g>
JMHO
--
later,
dave
(One out of many daves)
"Fred Mann" <fa...@bellsouth.net> wrote in message
news:v3QVj.1917$Kk3...@bignews9.bellsouth.net...
bl...@blah.com
JBWeld will not handle the heat. Period. They explicitly say on the package
not for exhausts and that its only good to 500 degrees, and honestly, I
don't even believe that. The exhaust there is probably closer to 1000
degrees. There is a product called "Hi-Temp Lab-Metal" (www.alvinproducts.com)
which is supposed to be good to 1000 degrees. Honestly, even that may
not be enough. As with anything, it is strongly recommended the surface
is clean, dry, oil-free, and sanded so it is rough to promote adhesion.
They also claim you need to slowly heat it to 425F and then keep it there
in order to reach the claimed 1000 degrees. I think you might stand a
chance of doing that with a heat gun. I think using the engine to do
it would be unwise.
(Disclaimer: I am in no way associated with Alvin Products or any distributor
of it. I have never seen, much less used one of their products in person.
In short, I'm not endorsing its use, only pointing out its existence)
Lost In Space/Woodchuck
much faster...
"Fred Mann" <fa...@bellsouth.net> wrote in message
news:v3QVj.1917$Kk3...@bignews9.bellsouth.net...
>
Brent P
> JBWeld will not handle the heat. Period. They explicitly say on the package
> not for exhausts and that its only good to 500 degrees, and honestly, I
> don't even believe that. The exhaust there is probably closer to 1000
> degrees. There is a product called "Hi-Temp Lab-Metal" (www.alvinproducts.com)
> which is supposed to be good to 1000 degrees. Honestly, even that may
> not be enough.
The red high-temp RTV works on exhaust manifolds. It survives the heat.
However any exhaust gasket repair like that it won't stay put for too
long.