Pre 74' Heat Exchanger fix??

[911 tweaks]

Does any one have a solution on how to replace the rusted away sheet metal on oe heat exchangers??
Any one making repo sheet metal to have welded on??
Thanks!
Bob

[Bill Verburg]

Before pursuing this any further it would be a good idea to be completely certain that the inner(pipe) sections are solid. The oem exhausts are designed to have the outer tin go first as a safty measure to prevent CO in the heated cockpit air.

[ratpiper71T]

If anyone's done this a write up with pics would be much appreciated. I'm planning to start a resto on my 71T in a few months after I finish remodeling my home. I was thinking about doing this to save the grand or so for SSI's. It appears that pelican sells what look like the inner pipes to replace.
This is my plan so far, not sure if this is going to work.
Either I'm going to have the HE's blasted or have them boiled out by a radiator shop or machine shop-to remove oil, carbon, rust etc., then somehow grind off the welds to the sheet metal and peel open the cover and replace the inner pipes, treat with POR -I think they have a coating that can withstand exhaust temps- then weld back up the sheet metal. If the sheet metal is porferated in some areas, well maybe I can source some good pieces from some junk HE's or more likley just template the broken areas with poster board then cut out a piece of sheet metal and bend it to form with some body hammers, then weld into place. Hopefully I can restore the muffler with similar methods if it's not already dust by the time I begin. Perfection on the welds probably doesn't matter that much- I'll probably use a flat grey exhaust paint on the hes and the mufller.
of course this is just my plan so far, never done this before.