overheating rodeo

[vihookline]

I have a '96 rodeo with 37k. Starts overheating going up hills or run at a steady 2200 rpm while in park. Changed water pump, changed radiator cap, changed thermostat, took out thermostat when a new one didn't work. Flushed engine out with hose, flushed radiator out with hose, checked clutch. Everything has failed, what's my problem.

Depressed in the Virgin Islands

[amigo-2k]

sounds like the radiator may be clogged

[95.5 Rodeo]

What the the coolant look like when you drained it? Rusty and dirty or bright green? It shouldn't be too bad with only 37K miles, but anything is possible.

When the Rodeo is warmed up to operating temperature, the top radiator hose should be fairly hot and the lower hose should be warm, not cool or cold. If the lower hose is cold, you have a bad thermostat or clogged radiator.

You can confirm if the radiator is clogged by removing the lower radiator hose. Using your garden hose, fill up the radiator with water. The water should drain out of the bottom of the radiator about as fast as you can fill it. If the water just dribbles out of the bottom of the radiator, you found your problem.

If the radiator is clogged you may be able to fix it using some cleaning solution. Otherwise, you'll need to get your wallet ready.


Good luck,
Dale

[vihookline]

Radiator has always drained very clear, even when using a heavy duty cleaner. The water has also flowed through freely through the radiator.
I hooked it up to my garden hose and was able to pump through water at about 30/psi with the same free flowing results. I have a real dilema that I just can't seem to resolve. It' depressing but please keep the sugestions coming. Thanks.

Ted

[95.5 Rodeo]

When the Rodeo is fully warmed up-

What kind of temperatures are you feeling on the upper and lower hoses? When you remove the radiator cap are you seeing any kind of flow inside? Does the coolant boil out when the cap is removed?


You said that the thermostat was replaced. Are you sure the spring is pointing toward the engine block and the jiggle valve is pointing up? If the spring is pointing in the wrong direction, it will never open up.

Is there a thermostat in place right now? I can't tell from your first post if there is or not.

How do you know it is overheating? From the gauge or is it boiling over?


Dale

[vihookline]

Just ran the car for an hour after being off for 24. Temp was in the very high range and the overflow tank was boiling. Thermostat is out now but double checked the new one when I put it in. Both hoses are hot and the water pump (new) is definitly working.

Ted

[rodeo02]

Is the clutch fan pulling LOTS of air thru the grill/radiator with the truck hot & idling? Could be a clutch fan issue. Also, try to stick with OEM thermostats. They seem to have less problems than aftermarket ones.

G/luck
Joel

[95.5 Rodeo]

You have mentioned that the engine has been allowed to run hot.

What does your engine oil look like? Any sign that water has been in it?

Have you seen any oil in the coolant or bubbles coming from the radiator while the cap is off? Do you see excessive steam coming from the tailpipe? (especially after running it for an hour like you said).

If everything in the cooling system checks out OK, you may have a more serious problem like a blown head gasket or cracked head / block from running too hot. Aluminum engine parts don't take very well to overheating.

I hope this is not the case with your Rodeo.


Dale