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New radiator cap leaking!

Chevyguy1450

NAXJA Forum User
I just recently started having a problem on my 99 xj, with my radiator cap leaking coolant when it gets to operating temp. It doesn't overheat but that's only because I keep adding distilled water almost every day. It doesn't spray out or anything like that, just drips out quickly when it gets warm.

A little background... I just bought the jeep a few months ago and about a month ago I took the radiator cap off to check the coolant. I found out the guy I bought it from had used tap water and there was a ton of build up on the cap and the coolant was not even recognizable as coolant. I drained the radiator then refilled it with 50/50 coolant/water. I also replaced the cap.

I already replaced the new cap thinking it was the problem. I know the xj's are kinda notorious for cooling system issues. Can anyone help me out?
 
Time to pull the spark plugs and look for signs of coolant in the combustion chamber. Also, look for bubbles in the coolant while the engine is running.
 
Check the seal of the cap first. Sometimes cheap caps don't make a good seal. If it's not an OEM or Stant I would get one.
Older or pre-'90 XJ's had cooling issues. Newer XJ cooling issues are mostly due to poor maintenance. Even the 2000-2001 head issues.
 
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