88 cherokee overheating
 

I have a 88 jeep cherokee that overheats.
What happens is that the temp gauge climbs way up and then when I shut the motor off, the water in the motor boils into the plastic resevoir tank which then all boils out of the tank. The electric fan on the rad never comes on while the engine is overheating.
I replaced the rad, thermostat and removed the water pump but the pump looks good. It shows no sign of wear and all the fins spin.
Anyone know what might be wrong? It seems to me that the water in the rad is cold while the water in the motor overheats.
Can it be the water pump even though it looks good?

Re: 88 cherokee overheating
 

sounds like restriced flow or air trapt in the system. possible you left the spring out of the lower rad hose? remember there is a lot of places for air to be trapt in the cylinder head

Re: 88 cherokee overheating
 

I'm having the same problem with my 89 jeep cherokee... I didn't notice the electric fan coming on either when it got hot (start of red line) after about 30 minutes and a little bit of reving to check oil and look for white spots to see if the block is cracked, the rad fluid started bubbling and was practically pouring out of the cap (no discoloration)... I was out today cleaning the jeep and letting it run on idle (which also seems low and inconsisitant 500-600 rpm) but that could be something simple. I'm kinda new to self-learning about vehicles too so... yeah..... what could I be looking at?

Re: 88 cherokee overheating
 

You could have air trapped in the system? Go to this website and read what they have to say about bleeding the system of the air: Jeep Cherokee Engine Cooling System - Burp Air System - Modification
(Do it when the engine is cold or you could get burned from the hot coolant)
Lets know if this fixes ur problem