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Please allow me to ask a few questions in order to better help resolve your concern.
Have you checked for emissions in the cooling system?
And what were the readings/results?
What are you talking about ?
I asked if you checked for emissions in the cooling system
and you said "yes"
what do you mean by emissions ?
Hydro carbons and Carbon Monoxide
I have been a mechanic for years and am now retired from the business and in my day we never checked for Hydro carbons etc.
This is a good test to check to see if the head gasket is blown
I have no way to perform this test,but there no oil in radiator or water in the oil
This is a good sign
You are looking for possible causes right?
yes,I am trying to find out why engine can set and idle for hours but as soon as you go on the road and travel up hills or under load its overheats to the point going into the Red (danger zone) Driving on interstate it run at normal temp
Good. That is exactly what I am I giving you. Some possible causes. I do hope that you appreciate my help. Now May I please give you some more possible causes?
If there are no emissions in the radiator, then the next two possible causes would be a plugged radiator and or a bad water pump causing this overheating condition
ok, I am inclined to agree with you,do you think it would help to flush the radiator even tho the coolant looks bright?
You could sure give it a try. However, my experience has been that when the radiator is plugged up, it will need to be replaced.
I have not had any luck in flushing a plugged radiator out successfully.
Does that make sense?
Does that help?
ok,when the engine is warmed up and the thermostat has opened,with radiator cap is off and I rev up engine rpms if water pump is working properly ,shouldn't water circulate to the point that it comes out of the radiator fill neck ?
To be honest, this is not a very reliable test.
Some vehicle do and some dont. It all depends on how the cooling system is designed.
ok,any suggestions on how to eliminate the water pump,I hate to replace it unless I have to because it looks like a bear to replace
You will have to remove it and then look at the impeller for damage
ok,anyway to check radiator for blockage?
I would check the temp on either side of the radiator to see if there is a major difference
ok,thanks ,If I have any further questions how may I get back to you?
YES, you may. Just one thing before you go
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