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Fix a plastic radiator?

While putting the transmission back into my friends cougar, we somehow managed to crack the top of the plastic tank of the radiator… right where the alignment tab slide up into the support.



it’s less than an inch long. My question is, can it be fixed or does he need a new one?



Would some sort of plastic epoxy hold?



It’s a brand new radiator and I REALLY don’t want to have to put a new one back in it.

to clarify my original post, the crack in the top of the plastic tank is right beside the alignment post/ tab and is less than an inch long.

Well for GM there is a hot melt platic kit available but it is only for repairing the core and not the tank. You might try something like JB Weld if you vee the area out but success would be doubtful. The plastic tank however can be replaced but you have to be very careful opening up the tabs and closing them in an alternate sequence or they will break or the gasket will leak. I’ve done it once before with success but the radiator needs to come out to get good access. Back then the tank cost about $35 if I remember right. Really though radiators are so cheap now . . .

It’s not worth a leak later either. I don’t believe there is a fix for that without removing the tank and getting it sealed from the inside. Once you get the tank off, it isn’t easy to put it back on without a leak.

If your labor doesn’t count, try a sealant and just hope it holds.

Thanks for the info. Guess the best option is to just tell him to buy a new one and replace it, If I ever get done fixing the damned transmission.

I really hate ford products…really really really hate them.

I would at least TRY to repair it…Drill a series of 1/8" holes along the crack, starting just outside the crack then right in the crack. With a Dremel Tool, grind out a little material along the crack to rough up the surface. Use slow-cure J-B Weld. The holes should anchor the repair and make it permanent…Clean the area with acetone or MEK before you apply the epoxy…

It may be better to weld it. Call around for someone with a plastic welder. They should have plastic welding rods which are of the same plastic as the tank.

Two part plastic epoxy works well also. I have a 96’ Cherokee that I did a roadside repair on and it’s still holding 6 years later.