cherokee92

I just had the 1992 Jeep Cherokee 4.0 in the shop to replace the rear brakes and cyllinders. The tech did a check on the rad since it had been leaking since I got the Jeep three weeks ago. I have changed the thermo, all hoses, and belt. he did a pressure check on the rad and it checked good. He replaced the cap with a 13 lb one and it checked good. He removed the cap and coolant came blowing out from the air pressure check. he looked inside the opening and noticed a small bump on ridge where cap inner seal would sit. When I got home and Jeep had not overheated at all wile driving - the Jeep had blown off cap and it was laying by air box. Overflow bottle lid was off. I talked to him about water pump and he said it was good. Could it be the rad going bad? The Jeep does not overheat at all and has a new thermo and cap like I mentioned with all new hoses. When Jeep is off and pressure is up it blows coolant out top of rad. If I run to temp it has coolant come out of top of rad. I did notice a 1/16 inch gap under cap when tight on rad. Is this normal? I think this may be the prob but not sure. Is changing the rad the answer?
We did notice that the rear brakes were gone from pass side and cyllinder was bad. did talk to used car guys and they paid for brake pads. Also emrgency brake cable spring was missing too. I had the drums turned as well. Nice to have brakes working. Thanks for any help. Wife and I are going crazy with this Jeep costing green. no engine or trans leaks at all and runs great otherwise. Has 174xxx on it. Paid for. Could rad be clogged or what...?

jeepfreak82

Whether it is the radiator or not sounds like it would depend on what the neck looks like where the cap goes on... If the cap got blown off, does it look like anything has been broken on the rad where it goes on? Also, the bump that you talk of may make it so that the cap does not hold pressure like it should but also should not make the cap come off. If the jeep has not run hot, then I would say that the radiator is not clogged and the water pump is definitely working.

cherokee92

Thanks. I worked on it in the rain which helped me keep cool. I used some sand paper and a spark plug socket to sand down the bump inside of the rad opening for the lower seal on the cap. I ran it to town and back and it is not leaking. I watched the rad flow back into the overflow bottle and still no leaks. I will get a new rad and maybe water pump in the near future. thanks for the reply. I hope this keeps on working and does not leak anymore. Have spent about 1 k on it since I got it three weeks ago. Another 1k and that would be what I paid for the Jeep.