Originally Posted by macdoe

Hello, I have tried to fix our radiator with some JB weld epoxy and it worked.....for awhile.

Last night we got home and I decide to look it over so popped the hood and had coolant sprayed all over my nice clean engine. We just did the head on it so up until last night I could have ate lunch off that motor....anyways, traced the leak easily to the top rad hose barb that I had repaired with the JB weld.

I had noticed when putting the car back together after the head work that the bung for the top rad hose was broken completely off. I thought one of the kids were in the garage and knocked it over and not said anything. I was starting to wonder where the broken piece went since I could'nt see it laying around on the floor anywhere, so I looked in the end of the top rad hose and there it was stuck in the end of the hose. I must not have noticed when dissassemby, anyways, checked out the repair options and decided since it said on the package that JB weld fixes some plastic that I would give it a try. I cleaned and prepared the surface very well and thought I did a good repair job but obviously not. It has failed.

I need this car working by tomorrow, so my question is this....I have a 1979 300D parts car with a rad and oil cooler in it. I was planning to use that rad but would have to change the oil cooler too since between the two cars is a different dimension. The 1979 model had no turbo and the 85 has a turbo. The 79 has a rad cap right on the top of the tank and the 85 has an expansion tank on the fenderwell with the rad cap on it. Will I loose cooling capacity changing over to the other (older) rad without the expansion tank? I also noticed that the 85 does not have the little metal tube that goes from the front of the cylinder head to the water pump, but the 79 does have this. Would I have to swap that little tube over to the 85 when changing the rad? I assume this little tube is for some sort of pressure bleed off. Why does the 85 not have this tube? does the expansion tank design eliminate the need for the small tube?

Is there another product out there someone has used that will fix this broken rad. I saw some plastic fuel tank repair stuff but it was triple the price of the jb weld. I am guessing that J.B weld is not compatible with coolant and it has worn away my repair.