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Several years ago I replaced the radiator on my '82 with an aluminum one. Later (still a while ago) I tried to remove the radiator cap and could not get it off. Basically I was lazy and removed a radiator hose to fill the system enough to use the overflow tank. Today I decided to try again to remove the radiator cap and can't get it off. It will move a little but for some reason I can't get enough leverage to push it in and twist at the same time. Probably because I have gotten to weak over the years (old age). Does anybody have any advice or tips or know of a new tool that can be used to get it off? I'm afraid if I try a pipe wrench on it I'll damage the radiator and be in a world of trouble. Thanks!
-Chris
Make sure it is cold, and you relieve the pressure first.
Your scenario is exactly why I use Stant caps with the manual pressure relief valve. The last time I removed a stock cap, I had to use channel-lock pliers. But that did work. Push with one hand, lefty loosey with the other.
The old radiator caps can get stuck sometimes. Try and gently tap on the cap will you are turning it. My old radiator cap was always a pain to remove, so I bought an OEM replacement and it seemed to be easier to remove.
Sometimes a radiator cap set of pliers, such as this one, can give you better leverage in removing the cap. Downward pressure while turning can be excessive at times. Make sure that the overflow hose or clamp is not interfering with your downward push of the radiator cap.
This is a radiator cap set of pliers from JB Tools. E-bay shows quite a few. Also, Snap-on Tools sold these at one time.
Last edited by Dave's82C3CE; Apr 29, 2026 at 02:17 AM.
I've tried to remove the one on my 80 that I recently picked up. having the same issue it will only turn so far can't seem to get a good hold of it with the fan shroud and things close to it. I might try the plyer's pictured above.
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I had a cap that I had use a channel lock pliers to remove. Once off I cleaned it and the radiator neck and put a small amount of lube on it. I then could remove it without the pliers.
Sometimes a radiator cap set of pliers, such as this one, can give you better leverage in removing the cap. Downward pressure while turning can be excessive at times. Make sure that the overflow hose or clamp is not interfering with your downward push of the radiator cap.
This is a radiator cap set of pliers from JB Tools. E-bay shows quite a few. Also, Snap-on Tools sold these at one time.
I ordered one off of Amazon. thing worked like a champ.
They make sticky rubber jar grippers for glass bottles with sheet metal lids that will work for this. Kitchen supplies. I have used them and they work for a few years until they loose their stickyness. Push down and turn.
Radiator Cap Removal
