903 heat exchanger”radiator” fitting for cap damaged.

[cruisintoo]

It is cut all most completely off at the surface of the steel tank. Recommendations range from epoxy,
silver solder or brazing. Everyone wants tank removed. Fifty year old bolt removals seems like a
nightmare of problems.
I’m thinking of connecting the fitting to the plate off the boat and then connecting it to the tank by drill and tap. The tank seems
Thoughts?

[SKYCHENEY]

I would remove the tank and take it to a radiator shop for repair.

[Bob Bradley]

Soak the bolts with Aerokroil for a couple of days. They'll free up. Just one more benefit to DD engines. The oil leaks prevent stuff from rusting up.

[whoover]

Take it off and the rad shop will braze a new one on and use a new 5lb cap. I did both of mine as they were almost rotted off. It's not a had job and the bolts will come out OK. It's a good time to have the shop clean the tube bundle too. It's heavy so have help and be careful with the bundle. They are rare and replacements if you find one is about 15k. I good seal shop can get you all the new quad rings you will need to put it back together.

Walt Hoover

[rwaldrop13]

Soak the bolts with Aerokroil for a couple of days. They'll free up. Just one more benefit to DD engines. The oil leaks prevent stuff from rusting up.

Hear hear! I had a can on Pau Hana and while my bolts were only 34 years old, I'd bet I had just as many challenges removing them. This was a game changer in loosening old bolts but even more important it soaked thru painted bolt heads and even freed up the cap on the heat exchanger for my generator. I counted rings, there were 6 layers of paint on that cap/heat exchanger.

https://www.amazon.com/sspa/click?ie...WxfdGhlbWF0aWM

[sgharford]

I have Cummins 903's and had the same problem you do. There was a guy - Dave Butler, in San Diego, CA who was a go to guy for 903's. His phone number was six one nine two two three eight eight two four. He sold just the part of the heat exchange that the cap screws onto. You can cut out the old section and jb-weld the new piece in. This is what he recommended and this was what I did about 15 years ago, and still going strong.