1991 4 cylinder overheating probelm

My daughter's 1991 is overheating. She lives about 3 hours from me. They took to a shop who said the head gasket was blown. So I towed it here and took it apart. I found no issue with the head gasket. Put it back together and it runs great (amazing....) but still overheats. It seems to push collant up and out of the coolant tank as it gets warm. I am thinking there is blockage somewhere. I flushed the radiator and the trans cooler. For the life of me I cannot figure out how to get at the thermo housing to pull and replace that. It is right up next to and underneath a motor mount. I did another test. When I run the heater I get no heat....

I am thinking avout trying to by pass the heater and see what happens but before I do that I thought I'd see if any of you guys have any ideas.

Thanks in advance.

Addtionally, I've checked the operation of the fan. While it does not come on by its self when the engine gets hot, when I jumped it and ran the engine it still overheated. So collant must not be flowing through the radiator... So it must be the thermostat, right? Anyone know any tricks for getting at the housing?

They can be particularly difficult to get all the air out of sometimes. It may now be air locked & overheating. Try pulling the upper hose and directly filling the engine through there. The thermostat housing in the lower hose flange is held on with two 10mm headed bolts. If you have power steering the pump should be removed.

They can be particularly difficult to get all the air out of sometimes. It may now be air locked & overheating. Try pulling the upper hose and directly filling the engine through there. The thermostat housing in the lower hose flange is held on with two 10mm headed bolts. If you have power steering the pump should be removed.

I'll give that a try. It does not look like removing the power steering pump is all that easy....

One question; if the heater core is blocked, would that prevent water from flowing to the radiator? It does not look that way to me as look at how those hoses are routed. The heater hose comes out of the end of the head and the hot water return to the radiator comes out of the middle.


Thanks

No, the water will circulate w/o the heater core. The P/S pump has one bolt on the frontside & two bolts on the backside, one is well hidden above the aluminum bracket. Once you figure out this it's not that difficult to drop down enough to get to the thermostat housing.

Dickboren, I'd leave the heater alone. Yes, go after the thermostat, it has to OPEN to get heat. Spend the $20 for the fan switch and get RID of that jumper! ....Y'doin'great!

I am going to try filling the engine from the upper radiator hose first... Its been raining so I've not wanted to go out there and mess around.

You'll be filling both sides of the thermostat. I predict a 'BURP-BACK'!..GOOD LUCK Though!

Well, that did not work. I guess I have to buckle down and replace the thermostat.

So I would like to file my application to the idiots club. Changed the thermostat, no difference. Suddenly I got the idea to inspect the coolant recovery tank cap. Found a failed o-ring. Replaced the cap and all is well.......

Now on to non-op power windows, door locks, and sunroof.

DB

Y'gettin'heat??

Y'gettin'heat??

I have not tested that. Btw, thanks for your help.

No, the water will circulate w/o the heater core. The P/S pump has one bolt on the frontside & two bolts on the backside, one is well hidden above the aluminum bracket. Once you figure out this it's not that difficult to drop down enough to get to the thermostat housing.


I just wanted to say thanks for your help. The information you provided helped me a great deal. Thanks again. DB