M-38 Water Pump Question...

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AMP
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M-38 Water Pump Question...

Post by AMP »

Greetings all Mil Jeep bretheren, First time post'r, long time fan....I'm restoring a '51 M38. I have a question regarding the water pump. My L134 water pump was shot so I purchased a new repro pump online. When I looked down into one of the larger holes in the pump I recieved I noticed what appeared to be an excess of flashing (likely from the casting process) in the pump (the hole seemed to be too constricted to allow proper water flow). Does anyone have knowledge/diagrams of how the water flows through the pump and how the bore for each of the water pump holes should look...I'm trying too determine if I need to grind out some of the flashing or if the casting was incomplete or improperly done somehow. Thanks so much for your time!
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wilfreeman
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Post by wilfreeman »

if I recall correctly, there shouldn't be any flashing in the inlet or outlet, and no obstructions. I tried the omix ada one also and it didn't have any obstructions (which is saying alot for them). The m38a1 pump is the same, as is the l134 pump (except for the pulley). Can you post a pic?
Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog)
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AMP
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Help....

Post by AMP »

ok, I'm technologically challenged...I have a few good pics saved to my computer now, but how do I post them to this forum so that you can see them? :oops: Thanks!
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wilfreeman
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Post by wilfreeman »

wes or ryan will have to set you up a gallery - just ask wes for a pic gallery. you can email them to me and I can post them for you until then.
wilfreeman@truvista.net
Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog)
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wesk
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Post by wesk »

Actually the M38A1, M170, & M38 as delivered from Willys share an interchangeable pump and pulley.
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
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wilfreeman
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Post by wilfreeman »

The best I can do on this phone:
Image
Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog)
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wilfreeman
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Post by wilfreeman »

And the other one. I'll post pics with the computer when I get home tonight:
Image
Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog)
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tob
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bad water pumps

Post by tob »

i also bought one from kaiser willys, and sent it back the bolt holes on the pulley didn't line up and weren't tapped straight bought a good on from midwest military.
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wilfreeman
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Post by wilfreeman »

That it's an omix ada pump, right? It is probably just a rough casting, if I am looking at the same part you are talking about (the neck of the inlet/outlet?). or are you talking about the jagged piece below the neck? I have been trying to remember what mine looked like.
Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog)
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AMP
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Post by AMP »

Yep, it's the area inside the water pump "inlet" hole that I'm referring to (pictures taken from two angles as you look down into the inlet)...I know there should be the cylindrical obstruction of the mounting bolt housing in the middle, but the rough material on either side of it doesn't seem like it should be there (there is a small irregular shaped black hole visible on the one side, it seems to me this should be much larger at least on the one side if not both of them?). I'm wondering if I should bother trying to grind the excess metal out with a drill bit or just send it back and go with another company...hence my original question as to how the water is supposed to flow through the thing...any and all advice is appreciated! Many thanks to Matt and other's who've responded so far!
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wilfreeman
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Post by wilfreeman »

I hate to say it, but I don't have a spare pump sitting around to compare. And I can't remember to save my life. Maybe somebody else can tell you. Sorry
Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog)
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wesk
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Post by wesk »

Water is sucked into the pump from the lower hose and discharged into the opening in the block.

Here are 4 of my US built pumps:
Image
Image
Image
Image
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
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AMP
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Post by AMP »

Perfect! Those pics tell me exactly what I needed to know! I thought that was how it should look...your pics confirmed it! Many thanks Wes!
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