The radiator cap?
Thread Starter
Burning Brakes
Joined: Nov 2005
Posts: 1,211
Likes: 2
From: Dumas Arkansas
The radiator cap?
I have one more question this early Christmas morning and I can't keep from thinking about my Corvette. I'd much rather work on the car or just go riding than go thru all these holiday meals. 
But I can not get the radiator cap off. I've tried to push down then turn it ccw but it wouldn't budge. That's the only thing that I haven't been able to check on was the radiator. Is there anything I can do maybe spray wd 40 to loosing it up? O'h it's a 92.
But I can not get the radiator cap off. I've tried to push down then turn it ccw but it wouldn't budge. That's the only thing that I haven't been able to check on was the radiator. Is there anything I can do maybe spray wd 40 to loosing it up? O'h it's a 92.
Racer
Joined: Dec 2004
Posts: 427
Likes: 0
From: Albuquerque New Mexico
Mine was a real PIA the first time I tried to get it off. If you look at the cap you can see your objective (the offset grooves and teeth that you must clear with pressure on the cap). Final solution? Support under the reservoir and a crapload of pressure on top to get the seal to squish down. I'm not sure how WD-40 would even help you. I wouldn't do it, I don't think WD-40 mixes well with coolant 
Instructor
Joined: Jun 2002
Posts: 201
Likes: 0
From: Fairmont WV
This tells me it has maybe been on for along time.
I would put a hot wet washcloth around it, let it go to warm. Put a channel lock wrench on it, push down and try a CCW turn.
I figure the rubber seal is holding you back.
I would put a hot wet washcloth around it, let it go to warm. Put a channel lock wrench on it, push down and try a CCW turn.
I figure the rubber seal is holding you back.
Melting Slicks
Joined: Jun 2002
Posts: 2,705
Likes: 30
From: Chesapeake Beach Maryland
2015 C5 of Year Finalist
I had the same problem, coupled with a bad cap seal that was creating a major pressure leak in the system and subsequent boiling sounds through the overflow tank. Anyway, as "drochau" has indicate, I supported the bottom of the tank really good with one hand while depressing the cap with a significant amount of pressure, while trying to rotate the cap off. It took several tries, and the worry of breaking the tank, but the cap finally came free. I replaced the cap with a new one and have had no gurgling sounds or overheating problems. I don't think a little WD40 on the outside of the cap will hurt. It will hopefully absorb into the old, dead seal and help loosen the cap. It doesn't take too much WD40 to do the job.
Good Luck
Good Luck
Thread Starter
Burning Brakes
Joined: Nov 2005
Posts: 1,211
Likes: 2
From: Dumas Arkansas
Thanks that did the trick. The warm rag with pressure on bottom of tank and pressed really hard and finally poped loose. Added some premix coolant fluid and ready to go. I think I may need a new cap. It was still hard to take off a second time.
