Radiator Cap Stuck on

[dreinert]

Seems obvious, I know.

Last week, I noticed the coolant in my reservoir was a bit low so I added some to the reservoir. I saw that some people have had problems with their radiator caps leaking so today I went to replace the steel cap on the end of the radiator and I was able to get it to twist 90deg but can't pull it up and off.

I then went for a drive and tried again when the engine was warm, not hot, and it still won't come off.

Any thoughts or things to suggest to try? I don't want to use extreme force with risk of cracking the plastic radiator neck.

I can certainly just take it to the dealer but it seems so basic...

Thanks,

Dallas
2019 Ram - 5.7Hemi w/Etorque

 

[Big White RAM]

I would try pushing down on the cap with your hand while turning. As I remember, most caps have a detent or tang to prevent them from popping off if someone were to open it up when the coolant was hot.

 

[stevj]

I would try pushing down on the cap with your hand while turning. As I remember, most caps have a detent or tang to prevent them from popping off if someone were to open it up when the coolant was hot.

True. Radiator caps have a safety feature that prevents the cap accidentally removing itself, and also to allow someone to loosen the cap and keep the hot coolant under control while spewing out when overheated.
As said, twist the cap countercloskwise until it stops, then push straight down to clear the safety catch and continue twisting. You should then be able to lift it out of its socket.

Steve