Speedometer's Fixed! How'd that happen?!

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jbjeeps
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Speedometer's Fixed! How'd that happen?!

Post by jbjeeps »

The speedo in the A1 started to act up yesterday: jumpy needle, inaccurate speed readings, failed to return to zero when I stopped.

So, I did a search on this forum, read about speedo heads, cables and drive gears, took out my Ord 9 and looked at the parts. Then started to take things apart. Unhooked the cable from the back of the speedo and spun the speedo, it worked smoothly, no grinding, returned to zero. So, I disconnected the other end of the cable from the transfer case. It spun smoothly, no catches or kinks. At that point I figured it must be the drive gear in the t/c. So I went on line and found the part I'd need, but before I ordered it I decided to put everything back together and check it one more time.

I took it for a drive and the speedo worked! Accurate speed readings, no jumpy needle, returns to zero whenever I stop.

So, what happened here? Maybe the cable was bound up, maybe it wasn't fully seated in the head or the drive gear, or . . .?

Whatever it was, I hope it stays this way.
1953 M38A1 (His)
1963 CJ5 w/Tuxedo Park Mk III (Hers)

See you at the Old Jeep Rendezvous in Ashton, Idaho 9:00 am - Noon on the first Saturday after July 4th. All pre-1970 Jeep vehicles, military or civilian, stock or modified welcome.
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wesk
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Post by wesk »

The most dreaded maintenance log entry on military vehicles and aircraft is: Could not duplicate malfunction!
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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AeroE
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Post by AeroE »

I had the same basic thing happen. Probably there was some debris or stiff grease on the cable and just removing and spinning cleared it. I used dry graphite lube on the cable & no problems since.

Although that doesn't explain the not-return-to-zero issue.
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wesk
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Post by wesk »

Not returning to zero is usually a needle movement sticking which may have been the issue all along and spinning the indicator drive rapidly could have knocked small dirt or debris out of the movement's way.
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
jbjeeps
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Post by jbjeeps »

Good comments guys, thanks. Just returned from a 50 mile trip on forest roads. Speedo still working.
1953 M38A1 (His)
1963 CJ5 w/Tuxedo Park Mk III (Hers)

See you at the Old Jeep Rendezvous in Ashton, Idaho 9:00 am - Noon on the first Saturday after July 4th. All pre-1970 Jeep vehicles, military or civilian, stock or modified welcome.
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