Overheating!!! 1991

[euro trash max]

1991 With 118k miles.

Looked around on this tech section and it looks like this is a pretty common problem with the 80's. It hasn't been too bad a problem for the most part. I've had a few times where it got high on the Temp gage, then when I got home I added some coolant or water to top off the radiator. I don't think it's leaking into the engine. There's no white smoke or milky oil. I replaced the plastic radiator with a fully metal one a while back(Re-Used the old cap). Still have not replaced the Thermostat or fan clutch yet. The last maintenance I had to do was the Alternator 2 weeks ago.

This morning it got really hot really fast. Usually it will cool off somewhat, but it threw the check engine light and was not backing down. My morning commute is only about 7 miles and it got that hot that quick. Outside temp was in the 80's I think. By the time I got there it was spewing steam out the overflow tube pretty bad.

I should be able to test the fan clutch, but I guess the Thermostat is a dive right in project. Will probably replace that one either way.

Any other suggestions other than the basics for now??

Also, side note, what's the PHH everyone is talking about??

 

[motorsargeT]

You have a 3f-e so no phh. the thermostat is a good idea to replace but i doubt it's your problem. If you have to keep adding coolant i would bet you have a leak somewhere. These can be difficult to find sometimes as there are a lot of small hoses throughout the truck for the heaters, oil cooler, bypass, etc. Try pressure testing the cooling system hot and cold and I'll bet you find a leak.

 

[80jay]

Hey euro ive been dealing with the overheating issue also, Ive replaced,rad,clutchfan,thermo,hoses, and radcap after all that the other day i was sitting at a light and the temp started to raise i also had the ac on, Im to the point were i will have to add a e-fan to the radiator and see what happens,

do you know if your leaking fluid or you just happened to notice the radiator was low. Replace the thermostat go from there.

 

[-Spike-]

Do the thermostat and cap, along with any old hoses you might have. Inspect the radiator, and check the fan. If your commute is relatively low-speed stop-and-go, pay close attention to the fan.

-Spike

 

[fernandol]

The leaks from hoses that connect to the oil cooler can be really hard to see, if the leak is small the coolant tends to evaporate before you can take a look, there is one hose that is behind or to the side (can't remember well, I have a 1fz now) of the water pump that is very hard to see and reach and can cause some headache.
I would try to take a really good look at all the hoses when the truck is really hot or, to be on the save side, pressurize the system with the engine cold and see if you find any small leaks.

 

[alkaline747trio]

Get under your truck and look for milky white stains on any hoses or hardlines, if you find any, trace those as far up/forward as you can and that is the area where your leak will be. I had one that I couldnt find for the life of me, but was under the truck for something else and saw the coolant residue, my leak was the hose that goes down on the drivers side of the waterpump under the engine to the oil cooler, 8" section of hose that looks to be a pain to get to.

 

[euro trash max]

thanks for all the tips...

Checked it out last night when I got off work. Radiator was really low. Added almost 3 gallons of antifreeze and water. Temp gage is at it's normal point now. Still need to do the investigation to see where the coolant is going????

Thanks again for the suggestions.

 

[GXO]

If you are missing 3 gallons you are SPEWING from somewhere and need to find that leak before you run it too much more. You will do damage to the all powerful 3FE if you keep that up.

The fan, thermo, etc is actually easy on that rig. I did it all in an afternoon.

over what period of time did you lose that much fluid? If short, you should stop driving and figure this out. If it isn't coming out the hoses, etc it is going somewhere...how does your cold startup exhaust smell? sweet?

 

[euro trash max]

DanKunz

No indications of any spewing coolant from anywhere. Possibly leaking into the engine and burning through the system. Never any sweet smells at startup. Usually takes a few months to drop down. I think I lost an extra gallon in steam yesterday.

Definite changes....
1. New radiator cap. looks ok, but the rubber is pretty rigid and dried out.
2. New thermostat.

Going to do a pressure test and see if it is leaking visibly somewhere.

 

[alkaline747trio]

Pressure test for sure, then have someone start the truck while you stand near the exhaust, sniff (not too close) for a sweet coolant smell, if you think you smelled coolant, you probably did, and time for a headgasket.