I just bought this jeep and it had overheating problems and was leaking from the heater control valve so i replaced it and also drained and filled the radiator, which was dirty with rust water.

After I had it all back together ... Stared up to run and now i DO NOT have hot air and the it overheats quicker than it ever did and hotter as well in the red zone.

 

Usually overheating can be attributed to a faulty radiator, water pump, t-stat, fan clutch, radiator cap, leak or a combination of any of those. Dirty/rusty coolant is what plugs the heater core and is a good indication of severe owner neglect when it comes to maintenance. Time for a little XJ TLC (tender loving care or maintenance).

 

As mentioned above, the rusty water suggests neglect. Wouldn't surprise if the rad is clogged due to nasty coolant, and even the heater control valve for that matter. However, if you did have heat at one point, I am wondering a fault water pump could cause all of these issues?

Bad Water Pump = No coolant Circulation = Overheating AS WELL AS no coolant circulating through the heater core.

Also, when you installed the new heater control valve, did you reconnect the little vacuum hose?

 

thanks man.. i m a dumbass and with the "new" heater control valve is different from stock one .. i hooked it up backward... so i flipped it around.. and what do u know.. .there is my heat...

 

Murphy's Law strikes again.

 

LOL don't worry man. We've all been there once or twice before. I went to replace my t-stat once a while back. Buttoned everything back up, and found my t-stat still sitting on the battery.

 

I did this one not to long ago. Also make sure the air is out of the system if you still overheat.