rectangular washers for fuel pump mounting bolts
- keats
- Jeep Enthusiast

- Posts: 342
- Joined: Wed Apr 13, 2005 6:00 pm
- Location: Middletown Ct
rectangular washers for fuel pump mounting bolts
A friend of mine working on his M38 threw me this question.
What is the purpose of the two rectangular washers that are used on the fuel pump mounting?
I did not remember any "rectangular washers" when doing my M38 so I looked further.
No mention of them in the maintenance manuals for removing and replacing the pump. No pictures anywhere. I have included links to both the M38 and the M38A1 Ord 9 manuals that list the washers, and a picture of them.
http://willysmjeeps.com/v2/modules/gall ... .sized.png
http://willysmjeeps.com/v2/modules/gall ... .sized.png
http://willysmjeeps.com/v2/modules/gall ... l_pump.jpg
What is the purpose of the two rectangular washers that are used on the fuel pump mounting?
I did not remember any "rectangular washers" when doing my M38 so I looked further.
No mention of them in the maintenance manuals for removing and replacing the pump. No pictures anywhere. I have included links to both the M38 and the M38A1 Ord 9 manuals that list the washers, and a picture of them.
http://willysmjeeps.com/v2/modules/gall ... .sized.png
http://willysmjeeps.com/v2/modules/gall ... .sized.png
http://willysmjeeps.com/v2/modules/gall ... l_pump.jpg
Gary Keating
1949 C3A, 1952 M38,
1954 M170, 1957 Cj3B
1949 C3A, 1952 M38,
1954 M170, 1957 Cj3B
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RonD2
- Jeep Legend

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- Joined: Wed Oct 01, 2014 6:00 pm
- Location: South Carolina, Dorchester County
Ok, after circling the trap watching for a reply, I can't resist. What a great obscure pointed question! Learning every day. I mounted my pump awhile back and mine are missing (need to study that manual better and take NOTHING for granted). I'm just a rookie spit-balling here. It seems to me that
(1) they protect the flange on the aluminum pump body from getting chewed up by steel lock washers?
(2) they allow the lock washers do the job because their square shape won't spin against the shape of the pump body?
(3) they spread the load of the bolts better through the pump flange and body?
(4) they prevent the bolts from penetrating into the block too far?
(5) all of the above?
(6) none of the above?
Looking to learn, and looking for 2 each 805842 washers. It looks like NOS may be available, but shouldn't be too hard to fabricate a pair if not. The only dim missing from the manual was the thickness.
Also discovered there's one more on the oil pump that I can't say for sure is there.
(1) they protect the flange on the aluminum pump body from getting chewed up by steel lock washers?
(2) they allow the lock washers do the job because their square shape won't spin against the shape of the pump body?
(3) they spread the load of the bolts better through the pump flange and body?
(4) they prevent the bolts from penetrating into the block too far?
(5) all of the above?
(6) none of the above?
Looking to learn, and looking for 2 each 805842 washers. It looks like NOS may be available, but shouldn't be too hard to fabricate a pair if not. The only dim missing from the manual was the thickness.
Also discovered there's one more on the oil pump that I can't say for sure is there.
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
- wesk
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Thickness is in the ord 9. Problem is the dimensions given are very odd for a rectangular washer:
0.406 diameter
0.660 ID
0.940 OD
0.0598 Thick
0.406 diameter
0.660 ID
0.940 OD
0.0598 Thick
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
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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RonD2
- Jeep Legend

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- Joined: Wed Oct 01, 2014 6:00 pm
- Location: South Carolina, Dorchester County
Thanks Wes. Lucky for me that Peter DeBella has them NOS just ordered. Saved me from fabricating some which can get ugly......measure it with a micrometer, mark it with a crayon, cut it with an ax....... 
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
-
RonD2
- Jeep Legend

- Posts: 2071
- Joined: Wed Oct 01, 2014 6:00 pm
- Location: South Carolina, Dorchester County
I received the NOS washers in NOS packaging. Unless I'm missing something <huge>, turn it and flip it any way you want, the bolt won't go in the hole:
[/img]
Oh well, chalk it up to another $15 down the drain...
[/img]Oh well, chalk it up to another $15 down the drain...
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
- wesk
- Site Administrator

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- Location: Wisconsin
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You learned another lesson as well.
During my 22 years in the military, when supply would ship us new stuff that wouldn't fit we were not allowed to throw it away. Instead we delivered it to the DRMO and it was then sold to public as surplus stock but seldom carried any warning markings for non-conformance.
During my 22 years in the military, when supply would ship us new stuff that wouldn't fit we were not allowed to throw it away. Instead we delivered it to the DRMO and it was then sold to public as surplus stock but seldom carried any warning markings for non-conformance.
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
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
- 4x4M38
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RonD2
- Jeep Legend

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- Joined: Wed Oct 01, 2014 6:00 pm
- Location: South Carolina, Dorchester County
Hi Wes, yes, well learned that in 25 years of doing electronics maintenance in the USMC........and this time I promise not to sell them to the next guy!
I might trim one a bit to see the fit....
I haven't checked this special washer on the oil pump yet.......more to follow.
I might trim one a bit to see the fit....
I haven't checked this special washer on the oil pump yet.......more to follow.
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
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skyjeep50
- Jeep Enthusiast

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RonD2
- Jeep Legend

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- Joined: Wed Oct 01, 2014 6:00 pm
- Location: South Carolina, Dorchester County
No problem expending a little effort. More curiosity wondering if that's what a mechanic 60 years ago had to do with a new part out of the package or whether it's like Wes said --- they were scrapped and the TM was never updated to reflect it? Searched photos and can't see if an original unmolested M38 had them installed......
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51
“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari
- 4x4M38
- Jeep Legend

- Posts: 3487
- Joined: Thu May 29, 2014 6:00 pm
- Location: Texas Hill Country
- dpcd67
- Active Member

- Posts: 187
- Joined: Thu Nov 24, 2016 6:00 pm
- Location: Iowa
What really should have happened is that the user would file a QDR (Quality Deficiency Report) back to the inventory control point, now TACOM, or DLA. They will inspect all remaining stock to see if they conform to the drawing. If not, then the entire lot is either returned to the vendor, or if too late, or the drawing is wrong, then they will be disposed via DRMO. Which is why, as indicated, never assume anything currently on the market as NOS, was compliant in the first place. I worked in TACOM for many years and this was fairly common for a number of reasons.
Assuming the square washer is correct which I have no idea. My M38 had no square washers under the long headed bolts which means nothing after all these years.
Assuming the square washer is correct which I have no idea. My M38 had no square washers under the long headed bolts which means nothing after all these years.