92 Caprice Classic V8 5.7L Overheating

[noskiveez]

A little background. Last summer the car would randomly overheat and we would switch the heater on and the temp needle would nose dive into normal range in 30 seconds. It made me think that maybe it wasn't really overheating.

This summer its started again. It gets almost into the red within minutes of driving it. There have been times where I turned and the needle went from almost the red zone to the normal range. Making me think its not overheating, but that nagging feeling tells me I need to know for sure.

The car will overheat within a few minutes. There were no visible leaks. I replaced upper and lower radiator hoses and refilled lost fluids. Driving it the first time, the upper radiator hose popped off and overheated. I initially thought it was the clamp being faulty ao I bought a new clamp. Installed new clamp. Same thing. Same hose popped off again. Put it back on and its leaking fluid around the hose some how.

I know the lower hose has a coil in it to prevent collapse, should the upper too (haven't seen it collapse)? Why might it be leaking around the hose?

Next is the thermostat. That will be repaced this weekend. I'm pretty confident that it isn't the engine block cracked or a bad head gasket.

How should I remedy this hose issue and what course of action should I go for next? Water pump?

[silicon212]

Thermostat.

[noskiveez]

Thermostat changed. Overheated Again. Popped hood and got a hot coolant shower. Water Pump bearings where it conects to the fan went bad. (Also the cause of the intermittent squeel) Caused water to run from bearings down the water pump to hose. wasn't a leaking hose afterall. New Water Pump on. Finish it up in the morning. This has been a long long day. No doubt, the thermostat change was just a perk for the car.

[silicon212]

That would do it too. I've also had that happen, but for some reason I was just not thinking about it.

[noskiveez]

I guess I really didn't think it could be the pump. It did this last year and we tore all thru it trying to figure itout. Unless it was functioning intermittently otherwise its been bad for atleast a year. Thankfully with as much money as we have put into coolant and distilled water over the last two weeks, the cost of the part didn't kill me and I found one local so I didn't have to wait for it. Bonus of living in a small town is you can call the parts store 5 minutes til close and say 'I'm on my way' and they will wait for you.

[j cAT]

Originally Posted by noskiveez

I guess I really didn't think it could be the pump. It did this last year and we tore all thru it trying to figure itout. Unless it was functioning intermittently otherwise its been bad for atleast a year. Thankfully with as much money as we have put into coolant and distilled water over the last two weeks, the cost of the part didn't kill me and I found one local so I didn't have to wait for it. Bonus of living in a small town is you can call the parts store 5 minutes til close and say 'I'm on my way' and they will wait for you.

because of the temps where you live , the engine coolant system must be under pressure. this prevents the boiling of the coolant. with any leaks the low/no pressure condition will cause the coolant liquid to boil and the water pump can not pump air bubbles. this causes rapid temp rise.

make sure there are no leaks. replace any soft hoses/bulging hoses. replace the pressure cap to the proper pressure I believe its 15 PSI on this model.

check that the radiator coils are clean.

at first reading your post I also though you had a sticking thermostat. when it pops open it can create a pressure pulse to blow off the upper radiator/goose neck mounted hose.

[silicon212]

How is your fuel economy? Does your car lose power at higher speeds? Ever smell a lit match or rotten egg?

A plugged cat will also cause these issues.