Mechanics

I HAVE A 89 CHEVY WITH A 5.7 350 AND IT KEEPS OVERHEATING I HAVE CHANGED THE THERMOSTAT AND THE COOLANT LEVELS ARE FINE TO NO AVAIL WHAT WOULD BE THE NEXT THING TO CHECK AND OF REPLACE?

1989 Chevrolet Silverado • 40,000 miles

The engine was changed about 3 years ago, my clutch fan still has tension but my coolant doesnt flow when the radiator cap is off it bubbles back up.
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Bughouse1220
December 3, 2011.



Fill the radiator then remove the upper hose at the radiator and do a flow test. Keep a running hose ready. Remove the cap then start it up. It will run until the thermastate opens youll see the water coming out the hose. Just refill the radiator and do it again and again. Youll see if the flow is proper.

Cadieman
Dec 3, 2011.
Radiator has good flow no issues there but still having a high temp. Changed the upper and lower hoses and that seemed to help its not over heating now but is still at a high temp. My thermostat is a 195 and the temp is stayimg steady between 230 and 240.

Tiny
Bughouse1220
Dec 4, 2011.
Does it overheat?Is the light coming on?Is the needle in the red? Possable retricted radiator. When its hot when you punch it do you hear a engine noise?If the radiator is for a 350 you should have the right tubes in the radiator. If the temp. Stays that high and its possiable the amount of rows in the radiator. The temp should run 230 or so then youll see it drop around 200 when the state reopens. Check for cold spots in the radiator. Do the flow test I said and watch the temp. Gauge. You should see the coolant flowing in the radiator. If still high your last thing replace the temp.
Sensor.

Cadieman
Dec 4, 2011.
It doesnt over heat but it gets real close almost to the red but not enough to make the light come on. I have also been lossing coolant. I think I may have a blown head gasket due to the loss of coolant and the smell of antifreeze in the exhaust. Thnaks for all you help.

Tiny
Bughouse1220
Dec 8, 2011.