Engine Overheating
 

Howdy y'all, I have a 1991 Jeep Cherokee with the 4.0L in it. I have had some overheating problems that I am trying to figure out. I started by changing the thermostat and that worked for a bit and then it stopped. So I got rid of my thermostat. Before that I had boiling in my degas bottle but no blown head gasket. My next step will be replacing the radiator. I have no leaks for coolant. It does have coolant in it as well. Would it be my radiator or would it be something else. Also when my engine starts to get hot sometimes my power steering boils. Which is very weird. What would be the cause of that as well. Thank you guys!


Also, I have the vacuum engaged 4WD system and I can only go into 4L because 4H is constantly kicked out. I bought a kit to install a lever actuated but is it hard to install into the vehicle?

Vacuum engaged 4WD? I have never heard of that in a Cherokee.

As for the overheating, you can replace pretty much the entire system for around $200. It's not a bad idea. Radiator, hoses, water pump, t-stat.

CAD
 

The vacuum operated CAD system was used in XJ’s and Comanches through 1991.

Yes, the majority of the cooling system parts can be replaced with relatively little cost. However, it would be best to use a good, strong cooling system flush to make sure the water passages in the engine block are not clogged. It would save a lot of time and money if you rule that out first before throwing parts at it.

True, but that would not prevent high or low ranges like the OP says...

That's good advice. Scale on the cooling passages will defy all attempts to cure the problem with new parts.

Just permanently lock the CAD and get rid of the vacuum system.