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View Full Version : JB Weld + Exhaust manifold=??



albersj51
08-27-2010, 06:21 PM
When I was working on my timing after the Pertronix install (Thanks Jac04) I noticed the distinctive sound of an exhaust leak. Get a moment to look back there and see a nice crack in the #4 exhaust pipe. What is the consensus on using JB Weld on this? I REALLY dont want to go through the manifold removal process (Ive heard the stories of broken studs!). I'd like to use JB Weld on it and leave it for a little while. Is this advisable or no? Thanks!

J

jac04
08-27-2010, 06:32 PM
JB Weld + Exhaust Manifold = Big stinky mess and the same exact leaky crack you had to begin with.

JB Weld is only good to something like 600 F (IIRC). Exhaust gas temperatures are more than double that. It just won't work. You can try some of the exhaust system repair kits out there, but I don't believe that any will hold up long term. Contact Bill at TNTLR and see if he still has any Genuine exhaust manifold left. That's where I got mine.

Get some PB Blaster (the real stuff) and soak all the hardware multiple times before trying to remove any of it. It will help a lot. Also buy new exhaust studs.

gudjeon
08-27-2010, 06:42 PM
I have brazed up cast iron manifolds before with a good success rate. If you take it to an old experience welder, they should know how to do it (do they even teach that anymore?) Preheat in an oven and braze liberally and let cool down again in same oven. Peining the weld lightly can help with internal stress relief. Cast can be arc welded, but I would advise against it as it is thin in that spot. Reassemble very carefully and evenly so as not to tweak it again for later.:thumb-up:

albersj51
08-27-2010, 06:52 PM
Thanks guys! I guess I will be going through yet another "right of passage" and getting a new manifold.

Gudjeon - Being a cheap, er "frugal" person, I like your idea. However, if I have to go down this road I dont want to go again, so I'll probably just pick up a new one. I see our hosts have one for $129...ugh!

Jim-ME
08-27-2010, 08:07 PM
Try Overland Engineering. Matt may have a good used manifold.
Jim