Stuck radiator cap?..i hate to waste a topic...but need help

[alvald83]

For some reason my radiator cap ('83) is stuck and i cant get it off. I got as far as turning the cap to line up the notches, then taking a screw driver to pry it up. Still cant get it to budge. Strange, it'll rotate freely but wont come off. I just hate break something and complicate the problem. Any ideas?

[Yammer Dan]

Should be able to see if the tabs are lining up. If they are I would try to pry a little if you have a cap to replace old one with.

[MiCarl]

If you've got the thing in the remove spot there may be some negative pressure in the system (although there shouldn't be). You could try pulling a hose loose (not the overflow though).

[dingy]

If the cap is not turning, the radiator grille has a tab on it that will interfere with cap twisting fully.

Lossen the screws holding grille to clear it.

No question is a waste, it cheers us up when we think we are being useful.

Gary

[Marcarl]

It may be stuck due to being in place for too long. Try a little heat around the neck of the rad,, better maybe a heat gun, rather than a torch.

[Pegasus1300]

I'm pretty sure you have to loosen the screws on the grill and move it around to get the cap off.I can't remember for sure but it seems to me there is a tab or something that holds it on.

[Flyinfool]

Are you sure you turned it far enough. You have to turn it till it stops and then push down on it and turn it a little more before the remove notches line up.

 

If it is the rubber seal that has gotten stuck you can loosen the cap and start the bike and just let it idle till it gets up to temp, the pressure should pop it loose. BUT BE VERY CAREFUL TO HAVE A RAG SECURED OVER IT AND STAY AWAY FROM THAT SIDE OF THE BIKE IN CASE IT LETS GO SUDDENLY WITH BOILING HOT ANTIFREEZE GOING EVERYWHERE. Have a hose ready to clean things up after just in case.

[SaltyDog]

On my 1983 Standard, I had the same issue with removing the radiator cap. When I looked underneath the cap at the tabs on the cap and the radiator neck, I saw that the plastic radiator grill also had a tab sticking up and preventing complete rotation.

 

I removed the grill and cut off the offending tab (not noticeable from above) and the cap rotated correctly allowing the cap to be removed easily. I work on my bikes on a bike lift so getting a good view of the interferring tab was pretty easy.

 

So you can loosen up the grill on the right side or take it off and inspect for interference, either will get you there. By taking the grill off you can cut the tab off and prevent future trouble.