Radiator Cap question
Melting Slicks
Joined: Nov 2014
Posts: 3,399
Likes: 1,339
From: Havre de Grace Maryland
Found this on the 'Net'. Not an answer from GM but some of it seems to make sense.
radiator - Why did GM change the pressure rating of their coolant tank cap for existing vehicles? - Motor Vehicle Maintenance & Repair Stack Exchange
radiator - Why did GM change the pressure rating of their coolant tank cap for existing vehicles? - Motor Vehicle Maintenance & Repair Stack Exchange
Race Director
Joined: Oct 2004
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How would the OP (or I) know which cap is 15psi, and which is 18psi? After seeing this thread, I went out to the garage and removed my cap. I can't find a part# on it anywhere, on the bottom, top, or around it. Any suggestions for us?
Melting Slicks
Joined: Nov 2014
Posts: 3,399
Likes: 1,339
From: Havre de Grace Maryland
I checked the original cap that I replaced with a 18psi and the yellow label on the top clearly indicates 15psi. Possibly yours grinder11 may have been replaced by a previous owner. The new cap is clearly marked 18psi.
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Last edited by grinder11; Aug 23, 2021 at 11:54 AM.
Race Director
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OK, went out to check cap, and there's no decal/sticker (anymore?). I ran Evans coolant at one time years ago, and it came with a sticker for the cap warning against adding any water to the coolant. I removed the sticker about 7 years ago when I went to Dex Cool. I may have pulled the original sticker off with it. If so, I didn't notice. My cap is all black, and only says "Warning, Do Not Remove Hot". That's it. I'm not having any boil over issues, or overheating issues, so I guess I'll leave it alone. Would just like to know.........
Last edited by grinder11; Aug 23, 2021 at 07:23 PM.
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I wonder what model year they went to the 18psi cap? Anyway, I think I'll take smoken1s advice, and have it tested. If I need a new one, I guess I'm a lucky guy, because I've certainly replaced more expensive parts on it!!!