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overheating..radiator hoses cold

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Old Aug 22, 2006 | 08:05 PM
  #1  
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Default overheating..radiator hoses cold

Just got done with my TT427.I have put 50 miles on the new motor. Suddenly the engine started overheating. I have noticed the upper and lower radiator hoses are cold when the temp gauge is reading 240. I am running Evans water pump and NPG coolant. I called them they told me to remove the thermostst and block the bypass which I did...still overheats. (please no comments like the coolant flows too much with the thermostat out..thanks).

I have evans pump / be cool radiator new hoses,,,seems like the pump is not pumping...I set up a tank out side the car hooked to the pump...there was flow but it seemed to be intermittent...and it didnt seem to increase with higher RPM's

Does this sound like a water pump flow issue? or something else....remember it happened with the thermostat in and out (blocked bypass). The system ran fine for 50 miles.

Fans fine.....coolant hoses cold when engine coolant temp is 240...

Please help...I am thought off obvious stuff......think I am going to have to remove pump

Tom Ulrich
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Old Aug 22, 2006 | 08:24 PM
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I would think that with everything you have tried so far, the water pump is shot and it's time for a new one.
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Old Aug 22, 2006 | 08:37 PM
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gotta be the pump, you should get a nice flow of coolant out of it, not intermittent
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Old Aug 22, 2006 | 08:42 PM
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I have seen these symptoms on several different engines of various makes and everytime it was the waterpump shaft spinning in the impeller. Unless you see water flowing well (which I do not see possible with cold hoses) replace the waterpump.
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Old Aug 22, 2006 | 10:32 PM
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Default overheating with Evans

It is difficult to fill a system with Evans coolant without bleed holes at high points in the cooling system to get all the air out. Either the system is not completely full or the impeller is loose on the shaft as someone else pointed out.

Could be the heater core had an air pocket when you filled the system.

You can check the impeller to shaft by removing the pump and pulling the cover off the back.

Steve




Originally Posted by tomulrich
Just got done with my TT427.I have put 50 miles on the new motor. Suddenly the engine started overheating. I have noticed the upper and lower radiator hoses are cold when the temp gauge is reading 240. I am running Evans water pump and NPG coolant. I called them they told me to remove the thermostst and block the bypass which I did...still overheats. (please no comments like the coolant flows too much with the thermostat out..thanks).

I have evans pump / be cool radiator new hoses,,,seems like the pump is not pumping...I set up a tank out side the car hooked to the pump...there was flow but it seemed to be intermittent...and it didnt seem to increase with higher RPM's

Does this sound like a water pump flow issue? or something else....remember it happened with the thermostat in and out (blocked bypass). The system ran fine for 50 miles.

Fans fine.....coolant hoses cold when engine coolant temp is 240...

Please help...I am thought off obvious stuff......think I am going to have to remove pump

Tom Ulrich
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Steve Demirjian
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e-mail: race-engine-development@***.net
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Old Aug 23, 2006 | 07:18 AM
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Im going with steam pockets.
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