Help Please! Overheating!!

My 93 jeep Cherokee keeps over heating if I drive more than 25/30 minutes. We've cleaned out the hoses (I had used stop leak a year or so ago and apparently that was a bad idea?) my boyfriend has taken the thermostat out thinking it would prevent it but it hasn't. There is plenty of fluid, no milky oil, I don't know what the problem is. Also, my heater/air conditioner doesn't work at all so I can't you that to help out either.

Sorry to hear about your overheating condition , sometimes it's hard enough keeping a 4.0 from running too hot as it is. Want to say that no one should ever run an engine without a thermostat as al that will do is just let hot water get hotter without letting the liquid in the radiator cool while the thermostat is closed . Thank goodness your not finding damage such as oil and coolant mixing , hope that never happens to you. I would say to just run hot water through the system until its clear ( I don't like radiator flushes , hard to completely rinse them) but your radiator and heater core sound like they are clogged . Disconnect the heater hoses at the firewall and see if there is any chance of clearing out the stop leak if it did not totally congeal. Keep an eye on the firewall condensation drain ( for a/c) to see if any coolant is coming out which would mean replacement of the heater core. For that , you got to get under the dash , I prefer to just pull the dash. As for the radiator , I don't think they boil out the ones with plastic tanks on the sides , might mean replacement if can't be boiled out if that is where your leak was originally . A lot of times those plastic tanks are the cause themselves. Sorry to bear less than good news but we would rather have you get a new heater core and radiator than see you cook a good running engine. Hope this helps. Greg
P.S.- welcome to Jeepz.com and thank you for your membership . Wishing you well and that all works out well too .

Replace the radiator with a factory one. My experience most aftermarket radiators decrease the cooling ability. Cherokees cooling system seems to be very temperamental.

desertrunner said:

Replace the radiator with a factory one. My experience most aftermarket radiators decrease the cooling ability. Cherokees cooling system seems to be very temperamental.

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Op never mentioned a aftermarket radiator.

Start cheap and easy.

First fully flush your radiator, engine and heater core. I use tap water to flush it use only distiller to mix with coolant and refill. I use super flush to help. Flush until only clean water drains from the engine.

Use only recommended coolant. Do not use Dexitron.

Replace the thermo with a new 195 deg thermo. Stant makes a good thermo.

Fill and burp the system. You need to be sure all the air is out and the expansion bottle is filled to the correct level when cold.

Verify all connections are tight and do not leak.

Once complete let us know how you fair.