Speedo Cable Question

1950 - 1952, M38, questions, discussions, regarding anything related to the M38.
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dpcd67
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Speedo Cable Question

Post by dpcd67 » Sun Jun 17, 2018 6:46 am

Will the speedometer core cable from an MB fit an M38 housing and work? I have a perfect waterproof cable housing but the inner cable is broken. Or one from a Cj?
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Re: Speedo Cable Question

Post by Joe Gopan » Sun Jun 17, 2018 8:11 am

No, two very different cables and casings, plus the type of drive ends of MB do not match M-Series. M-38 and M-38A1' share Cables and casings, but there is an early and late and they are of different length.
And for those who know zip about Jeep Speedometer Cables, the drive end is called a "blade"type, MB, CJ, etc., is "square" type and there are different thickness ends on square types.
AC used to make up Cable kits including correct blade drive and included a crimping tool. They, the kits, were discontinued in early 60's
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Re: Speedo Cable Question

Post by artificer » Sun Jun 17, 2018 9:07 am

This question is definitely not rocket science or requires specific Jeep knowledge to address.

Go to your local instrument repairer/supplier. They will make either an inner or outer or both, cable to suit your vehicle application.
The correct ends will be on your new speedo cable to suit both the drive & head ends, if the repairer knows exactly what you are after.
That correct information being transferred is your department.

Only after an inner?
Ensure the outer you plan to use has the correct fitments for both the transmission & speedo head & is not too short or too long.
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Re: Speedo Cable Question

Post by Radtech » Sun Jun 17, 2018 10:06 am

What is the length of your casings as I have a couple good cores.There were two different lengths of speedo cables on the M38 .Years ago you could have one made but not any more.Back 40 years ago you could go to an auto parts store and have one made.

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Re: Speedo Cable Question

Post by dpcd67 » Sun Jun 17, 2018 10:32 am

Yes, I remember the square end ones as I have had them made for other vehicles. but from what is said below, the 38 having a wing end makes it impossible for the local shop to make. They are out of business anyway. The square end was in it but the other end is not.
My housing is 60 inches long and came on the jeep.
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Re: Speedo Cable Question

Post by Radtech » Sun Jun 17, 2018 2:26 pm

There were only 2 speedometer cables used on the M38.54.5" and 56.75" the cores I have are for the early 54.5" cables.

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Re: Speedo Cable Question

Post by Joe Gopan » Sun Jun 17, 2018 2:52 pm

And one of those cable assy's was shared with the G-744 Tachometer.
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Re: Speedo Cable Question

Post by Radtech » Sun Jun 17, 2018 3:19 pm

The G744 tach cable is 63" long while the M38's were 54 and 56.

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Re: Speedo Cable Question

Post by dpcd67 » Sun Jun 17, 2018 3:28 pm

My housing is 59 inches measured along the outside of the curve and is a big rubber covered one. So, I have the wrong one looks like. Probably should just buy a whole new one then.
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Re: Speedo Cable Question

Post by Joe Gopan » Sun Jun 17, 2018 4:04 pm

I went and dug out my Ord 9's and Factory Parts Manuals for the M-38, M-38A1, and ORD 9 SNL G-744 (5 Ton 6X6).
The Part numbers for the cable Assys are below.
M-38:
ORD G-740 7527480---Willys 801093---EARLY
ORD G-744 7389881---Willys 805129...LATE (Longer)

M-38A1:

ORD G-744 7389881---Willys 805129 This is the later and slightly longer cable. It is actually a G-744 5 Ton Gas Tachometer Cable Assy and is shared with the M-38 and the M-38A1.
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Re: Speedo Cable Question

Post by Ken Perkins » Sun Jun 17, 2018 6:02 pm

bought a new one from Mullins a couple months ago...no more problems.
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Re: Speedo Cable Question

Post by dpcd67 » Sun Jun 17, 2018 7:22 pm

All the ones I found say they are 60 inches long. Above, it was stated that the long ones are 56.
Which is correct? My housing, which came off this M38, is 59 inches long. Probably 60 as I had to measure it around the bend as it would not lay straight.
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Re: Speedo Cable Question

Post by Joe Gopan » Mon Jun 18, 2018 3:14 am

The Casings outlast the Cable Cores, NOS Cores that match are hard to come by and there is no way to really tell if the Casing is damaged internally.. Try giving your MV parts Dealer the ORD Part Number or Willys Part Number. Some are advertising replacement complete cable assys at reasonable prices.
I have extra near new housings that were removed from M-38 Jeeps that had seized speedometers, I saved them for no good reason as as there was an ample supply of NOS Assemblys over the years. Also have some loose NOS cores that are wrong lengths.
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