My 1986 560sl has had a minor coolant leak at the neck of the reservoir that I have tried to repair a couple of times using silicone caulk with no success. I know poster Therling had noted in an older post that he used JB Weld but I resisted because I just assumed that dark gray would look so ugly. The small loss of coolant wasn’t worth doing that but it did create a mess of white residue near it. Before I plunked down the $80 or so bucks for a new one
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I decided to give it one more try. JB Weld now has available a whole family of epoxy products (mostly clear) that I thought might be worth a go. I ended up buying this one
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One of the reasons I chose this product was that it had a tip you attach that automatically mixes the two parts -saving me the task of doing it on a scrap of cardboard and then shoving it into a syringe. One time use though.
After cleaning up all the old caulk with a razor knife I used emery and a copper scrubber to make the area as clean as possible. I then used crazy glue in the thin gap between plastic and brass and let that set up.
The epoxy was very manageable to apply with the long pointy tip adaptor although I wish it had just a tad more viscosity because until it set up it did run a bit. But being practically invisible has its merits.
A side note: in the process of cleaning up the jar I did fish out a small piece of brass that appears to be part of the flange on the inside of the sleeve but running my finger along the inside I couldn’t find where it came from. That obviously is the cause -maybe some was too enthusiastic about screwing on the cap? No way to physically repair it from the inside as some else on this site suggested a while back.
Finished product. Waited overnight for things to cure and will report if problem is solved. Don’t know if others have experienced this problem but hopefully this is an option.
![Image]()
![]()
I decided to give it one more try. JB Weld now has available a whole family of epoxy products (mostly clear) that I thought might be worth a go. I ended up buying this one
One of the reasons I chose this product was that it had a tip you attach that automatically mixes the two parts -saving me the task of doing it on a scrap of cardboard and then shoving it into a syringe. One time use though.
After cleaning up all the old caulk with a razor knife I used emery and a copper scrubber to make the area as clean as possible. I then used crazy glue in the thin gap between plastic and brass and let that set up.
The epoxy was very manageable to apply with the long pointy tip adaptor although I wish it had just a tad more viscosity because until it set up it did run a bit. But being practically invisible has its merits.
A side note: in the process of cleaning up the jar I did fish out a small piece of brass that appears to be part of the flange on the inside of the sleeve but running my finger along the inside I couldn’t find where it came from. That obviously is the cause -maybe some was too enthusiastic about screwing on the cap? No way to physically repair it from the inside as some else on this site suggested a while back.
Finished product. Waited overnight for things to cure and will report if problem is solved. Don’t know if others have experienced this problem but hopefully this is an option.
