'95 CHEV G20 4.3 SMALL CRACK AT THE TOP OF THE PLASTIC RADIATOR HOUSING- HARDLY LEAKS WHILE RUNNING(RUNS A LITTLE HOT)- HOWEVER WHEN ENGINE IS SHUT DOWN INTERNAL PRESSURE FORCES LOTS OF FLUID OUT. GM USED TO MAKE AN EPOXY PATCH KIT THAT IS NO LONGER AVAILABLE-I USED LOKTITE 2 PART EPOPXY- IT LASTED 2 WEEKS (800 MILES) BEFORE IT BEGAN TO GUSH OUT AGAIN. ANY IDEAS BESIDE REPLACING RADIATOR. THANKS FOR YOUR TIME.
Quit wasting your time patching it. It needs to be replaced.
You risk major engine damage if you continue to relie on a patch job.
Those radiators that have plastic parts usually CAN’T be fixed. They MUST be replaced.
Run the truck by a radiator shop. Get their advice on patching; installing a new plastic tank; and replacing the radiator. They will have the most practical experience and have the advantage of seeing the crack.
Forget patching it. Easiest is to replace the radiator. If you go to a good radiator supply shop, you can buy just the plastic tank. I did it once and it worked ok but very stricky to bend the tangs and get it to seal properly. Also if there is one crack, there are more on the way especially if you pressurize the tank again.