overheating and no heat

[sniper7369]

Hey all, I have a 1990 Bronco, 302 EFI, A/C, 4X4. The truck is overheating and blowing coolant out of the overflow tank and blowing ice cold air out of the heater. If I top off the coolant I'll get heat until I park it and then the coolant boils over out of the over flow tank. I have replaced the thermostat and checked that it is installed the right way. The upper radiator hose gets hot and is pressurized (feels firm). Lower radiator hose is just barely warm.

There is no coolant leaking anywhere, the fan clutch appears to be operating properly.

Before this happened I would occasionally hear a loud chirping or screeching sound coming from under the hood, but it would stop after the engine started to warm up. Now it's not making those noises. I'm thinking it's probably the water pump, but I'm not sure.

ANY ideas would be appreciated before I start throwing parts at it. :blink:

 

[Seabronc]

It sounds like the water pump, but you could also have a clogged radiator. With the lower hose not getting hot, and based on the noise, (which could have been a pulley, idler, water pump, etc.) I'd sure have the water pump on the high end of my suspect list. It is impossible to tell for sure from here. What is your weather like? You say it doesn't over heat while driving?

>-

 

[sniper7369]

It does overheat while driving, pretty badly in fact. /emoticons/[email protected] 2x" width="20" height="20" /> Even while it is over heating though it's blowing ice cold air out of the heater. It's been right around 0 to -7 here the last few days. I did check the coolant with a tester and it's good to -40. When I get home from work (about a five mile trip) it's over heating, the over flow tank is full and the is coolant over flowing out of the tank. The upper hose is hot and firm, lower hose is warm.

 

[Miss Kitten]

my bet would be water pump as well too

i had an issue with my truck a couple years back and it overheated in -20 weather. it turned out to be something as simple as the gasket around the water pump not being on right

have you checked to see if there's any coolant leaking out of the pump or surrounding area?

 

[sniper7369]

I did check for leaks every where. I poked around under the hood with a Surefire flashlight for almost an hour, nothing. I don't know whats worse, the over heating or not having heat when it's below zero. )

 

[Seabronc]

If the coolant is full, you should get heat from the heater by the time the temperature gauge shows on the low end and before the T-stat opens. The heater circulation is done through the bypass hose on the front of the water pump if the pump is working.

Hope you have some place that you can get it out of the cold to work on it. Of course this crap never happens when it is convenient.

Good luck,

>-

 

[sniper7369]

Nope, no heat at all when the temp gauge is rising. At least I can get the front end of the Bronc' in the garage so I don't have to lay in the snow. /emoticons/[email protected] 2x" width="20" height="20" /> I hate it when stuff breaks during the winter. :angry:

 

[92bronco_in_progress]

most definatly the water pump, im about 95% sure on that one

 

[sumcirene]

well on my 88 302 EFI my heat problem was the heater core, the samething was happing to me except the overheating at first. after i changed my heater core my water pump went out(looking at the weep hole that is) changed out the pump and was good for a few days then i saw my ***** up....a little much on the bolts and pinched my gasket on the side. so had to redo the pump. good to go after that!

 

[Johnny Reb]

well on my 88 302 EFI my heat problem was the heater core, the samething was happing to me except the overheating at first. after i changed my heater core my water pump went out(looking at the weep hole that is) changed out the pump and was good for a few days then i saw my ***** up....a little much on the bolts and pinched my gasket on the side. so had to redo the pump. good to go after that!

when it warms up-----fell BOTH -water hoses and Both radiator hose--if the water hoses and radiators hoses are about the same tempereture-its surceilaiteing. If one radistor hose is hot and the other is cold---your radiator is stopped up. When it is COLD----look down into the radiator and see if your anti-freeze is clean or dirty.#2check the water pump. After you start it up let it run for a little while and shut it off. Get out and check for leaks coming out the bottom of the water pump. If you see antifreeze--the pump is bad. Also,get hold of the fan and see if you can wiggle it. If it wiggles--the pump is bad.

#3--pull the oil dip stick out and look for anti-freeze-if you see any-you may have a bad head gasket or cracked cylinder. If you see no anti-freeze--you should be ok--even though you put in a new thermosta--------you can still get bad ones.---------- You may need to check it again.----Good luck

 

[Dave429]

when it warms up-----fell BOTH -water hoses and Both radiator hose--if the water hoses and radiators hoses are about the same tempereture-its surceilaiteing. If one radistor hose is hot and the other is cold---your radiator is stopped up. When it is COLD----look down into the radiator and see if your anti-freeze is clean or dirty.#2check the water pump. After you start it up let it run for a little while and shut it off. Get out and check for leaks coming out the bottom of the water pump. If you see antifreeze--the pump is bad. Also,get hold of the fan and see if you can wiggle it. If it wiggles--the pump is bad.#3--pull the oil dip stick out and look for anti-freeze-if you see any-you may have a bad head gasket or cracked cylinder. If you see no anti-freeze--you should be ok--even though you put in a new thermosta--------you can still get bad ones.---------- You may need to check it again.----Good luck

There is one more possible peoblem, when you said you replaced the thermostat, did you do that because of this over heating problem, or did the overheating happen after you installed the thermostat, If it happened after you installed thermo. than you may have an air lock, easiest way to solve this is to turn your heater on to the max temp. with the heater blower motor on too, now you can do this next part one of two ways, Take the radiator cap off and start the engine and let it run untill it's good and warmed up and you know the thermostat is open (carefully look inside the radiator to confirn that coolant is circulating) and have water or coolent ready, if it is an airlock your rad. may bubble over a bit but if or when it does, keep the coolent level up,, and keep carefully checking that coolent is still circulating when it stops bubbleing over, coolent stops going down and your sure that engine is still at operating temp. then you should be done, the other way is pretty much the same but you would put the radiator cap on half way or to the first click (it's pretty much locked on but not sealed, this lets pressure escape) if this is not the issue then you may have a bad water pump or your coolling system must be clogged somewhere, try havving your radiator boiled-out or>>> rodded-out, this is when a radiator shop takes your radiator apart and shoves a rod through the cooling tubes, another way is to try a good radiator and engine block cleaner that will break the rust and corrosion loose from inside your block, radiator and heater core, but if you coolent isn't circulating than it may not work, the "air-lock" and "radiator and block cleaner" are what I'd try first then have radiator boiled or rodded out then water pump.

Hope this was helpfull, if not then you at least had something to raed for a few minutes.... /emoticons/[email protected] 2x" width="20" height="20" />