Hello I am new to the site and never posted on any site so let me know if i am doing any thing wrong.I have a 1988 4Runner 3.0 5spd 4x4 that is overheating.I used some stop leak and ever since it over heats. I have done the following,Flushed it several times and still using just water for now. I replaced the timing belt and water pump,removed the thermostat,new radiator cap,I have burped it several times.I had the radiator out and covered the bottom hole and filled with water and it seemed to drain fine.When it gets hot there is alot of pressure on the hoses.When i am filling the radiator it doesnt look like it is circulating very much. My fan is loud when i first crank it so belive its ok. It doesnt take a couple of miles to get hot either. The reason i used the stop leak is there was a small drip out of driver side head gasket.The leak has stoppped,no water in oil,no white smoke.Any help is greatly appericated and this is a great site so keep up the good work.Thanks Joey

 

Head gasket --check you oil too..

 

It sounds like the problem is with your head gasket. So you tried to fix it with stop leak. Which worked. But caused many more problems for you. That stop leak stuff is known for killing engines and cooling systems. It builds up in all sorts of places that you don't want it. I've seen threads in here where its built up around coolant ports in the block and restricted flow so much the only way to fix it was the take the whole engine apart and have the block cleaned. The guy ended up buying a crate engine instead. So much for a cheap, easy fix eh?

Since your head gasket was leaking before, we know that its bad. NOw the other issue lies in where the restriction is and if it can be fixed.

 

Thanks for your responces.I have never used stop leak before now and i never will again. I wish there was a better way of telling that it was the HG. It didnt run hot before just a small drip ever now and then.As I stated before no water in oil or oil in water no smoke etc.

 

The point is you've probably ruined both your radiator & heater core.

You're looking at a new radiator at minimum.

 

Thanks again for the help. I pulled the Radiator again and took it to a radiator shop to have it checked and cleaned. He said it was really stopped up good and was extra heavy so i will find out tomorrow if it fixes my problem.

 

Well I had the radiator cleaned out turn out that only 7 of the 36 lines were open. I put the radiator back in and its not running hot now. Iam having a problem now with it idling high about 1200 rpms. I checked for loose hoses but found nothing. Anyone got any suggestions?

 

Have you tried adjusting the idle after warmup?