TheSamba.com :: View topic

Sat Oct 31, 2020 10:30 am

Discovered this yesterday on the 3/4 side :evil:

I wonder if a competent old school muffler shop can weld this :-k

Sat Oct 31, 2020 10:42 am

That pipe looks seriously eroded. That crack is where the pipe looks paper thin or rusted out entirely. Likely most of the pipe is similarly thin and trying to even clean the metal enough to get a good weld would cause more holes. It might be possible to do a temporary weld on it but IMO that pipe is at the end of its useful service life. If I'm not mistaken that pipe is not connected to the heads and so it could be removed without the risk of snapping studs and needing to replace heads.

Sat Oct 31, 2020 11:13 am

Heh - that's a candidate for an epoxy fix. You'll be amazed how long it will last. What vehicle is that on?

Sat Oct 31, 2020 11:21 am

Thanks guys. I was thinking the same as both of you. Going on a road trip next week. Looking for a bandaid for the trip. I’ll do a proper replacement this Winter.

I have a lot of old school muffler shops around me

Sat Oct 31, 2020 11:27 am

Was my crack not a candidate for an epoxy fix because it was too close to the block?

Sat Oct 31, 2020 12:44 pm

i've successfully used the "2000 Degree" iron fortified cement in a little screw top vial on thick castings but anything i've tried on the Vanagon header pipes never bonds well. there is such a large thermal expansion coupled with a quite smooth surface that it all seems to flake off. there's quite a bit of flex in the exhaust system too which further stresses a hard compound.

it's a hard location environmentally... the header is red hot just inches beyond where it bolts to the head but the head flange is relatively cool. LOTS of differential expansion.

Sat Oct 31, 2020 12:52 pm

"Looking for a bandaid for the trip."

No doubt the metal is thin around that crack but could that crack be brazed?

But....

Cleaning that area to shiny metal might be tough and only serve to expose pin holes or worse.

Brazing a patch over it would bump the cost up I"m sure.

Neil.

Sat Oct 31, 2020 1:23 pm

Dan, gotcha. Makes sense.

Sun Nov 01, 2020 5:57 am

djkeev wrote: Case in point, the last time I tried I could not locally purchase plastigauge. A staple product in engine rebuilding.
I've been hitting the FLAPSes for various things during Dodge engine work and some places no longer sell valve lapping compound but one place had it and that's all I needed.