M38 Overheating

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redrad
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Location: Cresson, Tx

M38 Overheating

Post by redrad »

While driving Jeep last Sunday, it overheated to the point of steam coming out of radiator cap relief. I shut it down, and after it cooled off I removed radiator cap to add coolant, looking down into the radiator I cannot see the tubes because of some sort of baffle. My problem may be a stuck closed thermostat, so i will remove and test, but also i need to flush all the crud in the cooling system. the real question is how to know when radiator is full if you cannot see top of the tubes. I will attempt to attach pic from my album.

http://willysmjeeps.com/v2/modules/gall ... .thumb.jpg

Well that did not work out very well
Johnny D
1951 M38 Ser#1723
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keats
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Post by keats »

from the manual.


Fill the cooling system with water, or antifreeze solu- tion, of sufficient strength to protect the system against the lowest anticipated temperature, to a level approxi- mately 1 inch below the bottom of the filler neck.
Gary Keating
1949 C3A, 1952 M38,
1954 M170, 1957 Cj3B
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redrad
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Post by redrad »

Thanks for the info, Gary
Johnny D
1951 M38 Ser#1723
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redrad
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Post by redrad »

Image[/img]
Johnny D
1951 M38 Ser#1723
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OKCM38CDN
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Post by OKCM38CDN »

IMO time for a good flush...
Hal, KB1ZQ
TSGT, USAF (Ret)
1952 M-38 CDN CAR 52-31313
1952 M-100 Strick #104
1951 Willys Wagon (For Sale)
1954 Willys M38A1 201001205
Tornado Alley
Del City, OK
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Mike_B
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Post by Mike_B »

If it were mine I'd pull the radiator and turn it upside down and flush it backwards with the garden hose. If you put it on top of a 5-gallon bucket you can catch the junk and see how bad it is. Don't pressurize the radiator, just let the water run free. so you don't split a seam.

You can also run water down the thermostat hole and back flush the block as well.

Mike B :)
Mike B
1953 M38A1 Brush Truck
1952 M38
1951 M100 Trailer
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redrad
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Post by redrad »

Next warm day I am pulling thermostat and flushing engine and radiator,
Thanks as always for the tips
Johnny D
1951 M38 Ser#1723
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JBJeep
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Post by JBJeep »

Lord knows, I'm no mechanic...but with every restoration I have done, cleaning/flushing/repairing or replacing the radiator is one of the first things done.
If you don't know the service history of a car and you plan on driving it, it just makes sense.
1955 M38A1 MD 82551
Former owner/restorer of 1977 CJ-5, stock with factory V-8.
Used as a daily driver for seven years.
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