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Cooling issue!!!

AzXj1002

NAXJA Forum User
Location
corona
I just replaced the thermostat in my 90 Cherokee with a closed system. For some reason, when I shut the vehicle off fluid starts coming out of the overfill bottle and it's acting like it's not wanting to circulate.

I need help asap, on my last 3 day permit to get this thing registered and it's day 2!!

949-547-2143 Matt
 
make sure your cap is good.
...and make sure your pressure bottle isn't cracked. Spitting up coolant and not holding pressure is a cap and/or botttle AND air in the system problem.

Bleed it just like WebDog says...but I must add...do this while adding coolant to the tank, and with the engine off and cool. Once you stop getting bubbles, put the sensor back in, being careful not to twist off. They're fragile sometimes. Don't add thread sealer or teflon tape as the sensor grounds through the block.

I'd be examining the bottle and cap and I'd bet you a beer (Sierra Nevada) that either/both might be compromised. You can buy a cheap replacement on Ebay and expect to replace it again next summer, or invest in one of those metal tanks with a "real" radiator cap. You could even get a botttle and cap from an 80's - 90's GL Volvo as those are rumored to work well (no personal experience).

Anything beyond that might also justify converting to an open system, IMHO. I've done it on both my RENIX Jeeps and it's, if nothing else, more predictable and I can troubleshoot it better. I have limited brain space.
 
Get rid of the closed system. After 2 years of fighting my wifes 89 I finally converted it to a open system. All this summer it never lost any antifreeze and runs 5-10 degrees cooler.
 
Don't know about when they started using a closed system but I know 90 is the last RENIX/closed year. There may have been some bleed over into 91 I've heard, but never saw.

Both my RENIX rigs are open system, I was tired of buying cheap Chinese knockoff bottles and caps.
 
Well now for some reason. It is cranking. Over on itis own. Anyone have an idea what. Thatis?

Did you just buy this jeep?

Sounds like a stuck starter, starter solenoid, or stuck ignition switch. Could be either one.
 
Get rid of the closed system. After 2 years of fighting my wifes 89 I finally converted it to a open system. All this summer it never lost any antifreeze and runs 5-10 degrees cooler.

I solved the Renix closed system problem 2 years ago (and posted the story in three threads, one on the bottle and cap, and two on the inline filler neck). I use a volvo cap, on the ebay Renix bottle, I added a 3/8" brass nipple to the inside of the bottom plastic nipple, and an inline filler neck with a stock radiator cap to the upper radiator hose (makes getting air out of the radiator a piece of cake). Mine runs at 200 F tops, on 105 F days in Humid Houston with the AC running on max parked on the freeway in 5 PM traffic, at only about 9 PSI!!!!! No leaks, or fluid loss in two record heat wave summers here now.

The closed system, runs at a lower pressure than the open system!!!
 
Does anyone know what years were closed systems and what years were open?

Jeep went back to the open system in 1991, but many new cars since then use the closed system. Closed systems are superior, if you have the right hardware. The current plastic bottles have two problems, the cap is junk, and the lower nipple needs a metal reinforcement like the side nipple has. And the screwy upper hose and plumbing traps the radiator about 1/2 full of air that defies purging.
 
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