Extra coolant Line

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southpw
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Extra coolant Line

Post by southpw »

So I ccan't figure out the coolant setup from the previous owner of my L -134 engine and could use some help.
I'm confused as to why there is an extra line running to passenger side of the block. I believe the proper routine for the M38 is just a hose running from thermostat housing to upper rad and water pump to lower rad (and short 90 degree bypass hose from water pump to cylinder head. Any input on the pros and cons of this current setup is appreciated.
Brad

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1952 M38 project
Brad
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4x4M38
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Post by 4x4M38 »

Wow.
southpw
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Post by southpw »

4x4M38 wrote:Wow.
well that wasn't very helpful Brian :)
I take it you have not seen this before?
1952 M38 project
Brad
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4x4M38
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Post by 4x4M38 »

Sorry.

No Sir. I had a civvy cooling line teed off where the temp gauge
goes and into the water pump. Got the tee issue resolved,
bypass fitting in the head where it belongs then twisted off the
fitting in the water pump. Finally got that resolved with the
correct bypass hose.

Have not ever seen a hard line coming off a block hose
fitting. That is a new one. I didn't even know there was
a pipe connection there.

But your assumption for the correct setup is spot on.

Take care,
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DJ
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Post by DJ »

engine heater?
51 M38 ,52 M38 ,53 Jeep PU ,62 M 37 ,68 M 715
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wesk
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Post by wesk »

That is the drain valve location. Someone used it for an engine heater hookup. The 1st series 641087 casting had the drain valve in that boss. The 2nd, 3rd & 4th series 641087 blocks had the drain valve in the next boss aft behind the dipstick tube.

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641087 Series 1

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641087 Series 2

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641087 Series 3

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641087 Series 4
]
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804380 casting
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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southpw
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Post by southpw »

Thanks Wes. So I have the earliest 641087 block I guess. Any idea how early? I have the Oval boss on the side of the block but can't get the numbers from it and also can't read the numbers on the pad above the water pump. Both show signs of stamped numbers but unable to determine the numbers. (This is a gear driven block, no chain)
thanks
Brad

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1952 M38 project
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Post by 4x4M38 »

Brad,
You have serial numbers there. Google or search recover engine
serial number for some ideas. Mine was so completely machined
I'd probably have to use magnetic particles or acid.
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wesk
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Post by wesk »

Brad,

Concentrate on the prefix area. You are looking for one of the following:

J
2J
T
U
V
MC
RMC

Do not use anymore abrasives on the serial pad. Use paint stripper or Coca Cola.

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Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
southpw
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Post by southpw »

Paint stripper it will be then. Thanks
1952 M38 project
Brad
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