Cooling system issue-99 Cherokee Laredo
First off thanks to anyone who can give me some assistance sa I don't know where to begin. So my wife is driving to work and while at a stoplight she notices warm air blowing out of the vents (cold air was turned on). When she parks the car and turns it off antifreeze gushes out on the ground. When I get there I notice that there is still some in the reserve tank and still some in the radiator. I fill it up with water and drive it home. On the way home I notice that it is actually running cool...getting maybe a quarter of the way up the temp gauge. Nowhere near 210 range. It makes it home fine and I let it idle for awhile and it eventually starts to run hot and warm air comes out of the vents...but I don't see any leaks??? Anyone ever run into this?
Old fart with a wrench
Joined: Nov 2010
Posts: 14,398
Likes: 741
From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
I would quess thermostat. Sticking closed. Try replacing it and see what happens. I've seen thermos stay open after an overheat for a long time and then snap shut and never open again! The coolant on the ground is probably what's known as "afterboil". If you've got hot spots in the engine due to air pockets, the coolant will flash to steam after it stops circulating, causing it to spue out thru the overflow tank. This is the MAIN reason NOT to open a hot radiator cap. Pressure keeps it from boiling until you release it, and then you get soaked with scalding coolant! I know a guy who wound up blinded after opening a radiator with the temp guage reading 260!!! Yup! He was drunk!
I had a similar issue, but my Resev. tank actually cracked. But occasionally would Idle high after starting up and eventually drop to normal idle. Are you suggesting its a thermostate issue? or a throttle control issue?
Old fart with a wrench
Joined: Nov 2010
Posts: 14,398
Likes: 741
From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
Check the recent posts. One guy had similiar issues and found a shattered water pump impeller. Check the pressure cap and any other cooling system parts.
It's hard to do diagnostics from afar.
It's hard to do diagnostics from afar.
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