I just picked up a cheep 86 4runner. He said it was pushing coolant out of the overflow tank. I got it home filled the rad up with water started it with the radiator cap off and watched it. After about 3 mins the water started to rise and then flow out of the radiator neck. The temp was still not reading the water was cold. I put the radiator cap back on and took it down the block and back got the temp up some. Turned the engine off. I felt the top of the radiator it was still cold. So I loosened the rad cap and it had a lot of pressure under it when the water came spraying out, but the water was cold?? After it sprayed out for a bit the water started to get warm but it wasnt even that warm. Anybody have any awnsers for me. I bought it thinking I would be putting a head gasket on but now am thinking it might be something else.

Thanks a lot, Brant

 

sounds like a blockage of some sort, try runnin water through the block and pull the hoses to see if if they are clean. that would be my first check is the simple things. hoses, and thermostat.

 

Thermostat has just been changed as well as the rad cap. The previose owner said he had put some rad stop leak in it so maybe thats the blockage.

also the engine will get hot if its running and not moving. but if driving it will cool back down.

 

Sounds like the water is boiling in the block and forcing the water out. Thermosat, water pump, or radiator. The radiator doesn't sound clogged or the water wouldn't be pushed out. When the thermostat opens the water should flow through the radiator if the water pump is good. Water will move from the block to the radiator with steam from the water boiling in the block.

 

Another thought could be an air bubble in the system. These things are tough to burp. Get the front end as high as possible, using ramps or whatever you have, so that the cap is the highest point in the cooling system. Keep adding coolant as the air burps out.

That's where I'd start, anyhow.

 

RobD is on the right track I do believe.

22Re is known for this burping issue...I believe some folks even snake some tubing in to help reach the air bubble. A shop I used would do some panic stops to force the water to travel to all reaches of the system. Running with heater full on is another method.

It also sounds from symptoms like the radiator itself is blocked -you allude to this yourself stop leak in use?-so measure how much is going in after a full drain.

it's newbie tech so as politely as possible I am suggesting a search of "burp" and you might find a wealth of info. Even google search may lead you to other ideas. Page backwards in the 1st gen Runner or even 2nd gen section and you may run across it that way also

 

I am leaning towards either towards a blocked radiator these are getting older.

Also the possibility of a air bubble is also pretty good . What I do to all my 22rec engines is put a tee in the heater hose making it the highest point in the system to bleed the air out.

Why was the stop leak put in where you told??

Good luck

 

IMO, its the head gasket. I was having the almost exact symptoms. I kept doubting it until I started it one day and it started billowing white smoke. Changed the head gasket for about $160. Has been perfect for nearly 3000 miles. I used OEM parts.