Overheating Issues

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bazookajoe
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Overheating Issues

Post by bazookajoe » July 10th, 2019, 10:10 pm

Took my A-2 for a ride tonight "about 9 mi." and noticed it was getting up to 220 degrees. The radiator has been flushed and the antifreeze was up to the proper level. When i took the cap off it didnt seem as though the water was moving. The system was pressurized when i took the cap off so i dont think its a bad cap. What do you think is the most likely culprit ,bad water pump or stuck thermostat. The belts are tight and turning the pump. I have only put 100 miles since i restored it but it is driven very infrequently.

Mark
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Re: Overheating Issues

Post by Mark » July 11th, 2019, 2:23 am

do the hoses feel hot?heater hose, radiator, coolant, check the thermostat?
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

Cobra5
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Re: Overheating Issues

Post by Cobra5 » July 11th, 2019, 9:08 am

Are you going by the reading on the temp gauge or was it noticeably overheating? Do you have a infrared thermometer? You can get it up to temp again and take a reading at the temp sensor for the gauge. It could be as simple as a faulty sensor or gauge. Did you change your thermostat as part of your cooling system flush? Did you rebuild the engine as part of your restoration? Is the water pump making any noise?

rickf
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Re: Overheating Issues

Post by rickf » July 11th, 2019, 10:08 am

Those gauges are notoriously wrong, check with an infrared gun. Due to the top baffle in the radiator it is almost impossible to see any coolant movement.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

bazookajoe
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Re: Overheating Issues

Post by bazookajoe » July 11th, 2019, 10:34 am

Yes i changed the thermostat, hoses are hot,coolant level correct level,cap holding pressure. I have heard of water pumps leaking ,I just dont see how it wouldnt pump water. I think i will change the thermostat first.Also i can tell its overheating not just inaccurate gauge. I will tell more tomorrow.

Fil Bonica
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Re: Overheating Issues

Post by Fil Bonica » July 11th, 2019, 11:02 am

Had a friends jeep with the same problem.
Come to find out it was a clogged radiator core.
The center of the core was blocked. Getting a radiator boiled out is getting to be a problem.

Fil Bonica
K1ABW

Cobra5
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Re: Overheating Issues

Post by Cobra5 » July 11th, 2019, 11:21 am

You can use an infrared thermometer to check your thermostat to see if its working. Take a reading on the block side and than the hose side. If the thermostat is closed you'll have a noticeable temp difference between the two areas. Another way to check your water pump is working properly is to get the engine up to operating temp. Use a rag or good pair of gloves because the hose will be hot and than squeeze the upper radiator hose and slowly release. As your releasing your grip you should feel water moving through the hose. This is if you know your thermostat is working properly. You can also check your radiator with an infrared thermometer to see it's plugged. There's a possibility that the radiator became partially clogged during the flushing process.

rickf
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Re: Overheating Issues

Post by rickf » July 11th, 2019, 3:32 pm

While it is running at high idle run the infrared thermometer across the radiator top to bottom and side to side and see if there are cool areas. If so they are the clogged spots.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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