I have an 00 4.0 Tj. I’ve had a problem with it losing coolant over a pretty quick time frame. I had a mechanic look over it and said everything checked out fine and we replaced the thermostat. However, nothing had changed and it continues to happen. After a good 20-30 min drive I can hear bubbling when I get out as if something is being boiled. Not sure what to do, any ideas ?
Losing Coolant
- Thread starter chasecarter
- Start date
Rooster1987
Member
Are you getting milkshake oil? Are you seeing white smoke out of your exhaust? Chances are with the 4.0 it’s a blown head gasket or exhaust manifold leak.
If you’re losing coolant you should be able to figure out where it’s going. If not, then I would start by burping the air from the system, if that didn’t work I’d replace the radiator cap, if that didn’t fix it start replacing hoses, if that didn’t stop it I’d replace the radiator.
If you’re bubbling that means you’re boiling and therefore have a depressurized system and the coolant is evaporating.
I was losing coolant as well, but I was getting the ol chocolate shake in the oil so I knew that was a blown head gasket and/or a cracked head. Yours sounds like a lesser issue, but one more frustrating to diagnose.
If you’re losing coolant you should be able to figure out where it’s going. If not, then I would start by burping the air from the system, if that didn’t work I’d replace the radiator cap, if that didn’t fix it start replacing hoses, if that didn’t stop it I’d replace the radiator.
If you’re bubbling that means you’re boiling and therefore have a depressurized system and the coolant is evaporating.
I was losing coolant as well, but I was getting the ol chocolate shake in the oil so I knew that was a blown head gasket and/or a cracked head. Yours sounds like a lesser issue, but one more frustrating to diagnose.
The 2000 and 2001 heads can crack. Take the oil cap off and look and see if the head is label tupy or not.
https://wranglertjforum.com/threads/how-to-identify-0331-or-tupy-head.8112/
https://wranglertjforum.com/threads/how-to-identify-0331-or-tupy-head.8112/
2000-01's are prone to cracked heads. My 00' XJ was mysteriously losing coolant with no leaks, no smoke or smells. The radiator always stayed full, but the overflow jug would go empty. The oil looked fine and it ran fine. Mechanic said nothing was wrong with it. It was a cracked head.