Speedometer drive gear 5704838

This is the place to get help with technical matters concerning your M151 jeep

Moderators: rickf, Mr. Recovery, raymond, moose53

Speedometer drive gear 5704838

Sponsor

Sponsor
 

Speedometer drive gear 5704838

Postby Krempely » October 21st, 2018, 6:01 pm

The speedometer in this 1964 M151 has never worked. I assumed it was a faulty cable; tip appeared broken off. I recently installed a new cable. I manually turned the cable and the speedometer reacted as expected. I then installed a new cable into the drive gear on the transmission and took it for a test drive. There was no indication on the speedometer. I removed the cable and it was not damaged. I removed the speedometer drive gear from the transmission and this is what I found. The drive gear appeared to have been inserted beyond the retaining seat (hole). The drive gear appears ground down and the shaft. Is it possible the gear was "dropped in" by the previous owner, or perhaps the gears fail over time; lack of gear oil?

Image

Image

Image

Image

Image
1964 M151
1943 MB
1952 M135
1984 M1009
Krempely
Private
Private
 
1 year of membership
 
Posts: 4
Joined: August 24th, 2017, 4:32 am

Re: Speedometer drive gear 5704838

Postby rickf » October 21st, 2018, 6:47 pm

You can see that the wear pattern was made by the side of the gear forward of the speedo shaft. The really big question is how in the world did the shaft get over there?! It had to be out of the bottom bushing to do so and the wear appears to be roughly even top to bottom from the pictures. Not like it was cocked in there. Unless that gear housing is worn very, very badly I just can't picture that. UNLESS, the gear moved back! I will have to look that up and see what gear it is and what is holding it. I will get back to you.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone
rickf
General
General
 
10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership
 
Posts: 15379
Joined: November 26th, 2007, 12:28 pm
Location: Pemberton, NJ.

Re: Speedometer drive gear 5704838

Postby Fil Bonica » October 21st, 2018, 8:59 pm

Had a similar failure some time ago.
The cause was a loose bolt holding the transmission brake wheel.
The looseness cause the gear trainnto open up and destroy the speedo gear.
Replaced the brake wheel bolt and speedo gears.
All things are well to this day.

Fil Bonica
K1ABW
Fil Bonica
Brigadier General
Brigadier General
 
10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership
 
Posts: 2457
Joined: December 9th, 2007, 9:49 am
Location: Falmouth, MA

Re: Speedometer drive gear 5704838

Postby rickf » October 22nd, 2018, 9:16 am

Looking at the -34 I would have to agree with Fil, I see no retainer on that rear rear set so if the parking brake drum comes loose there appears to be nothing to hold those gears from moving back.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone
rickf
General
General
 
10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership
 
Posts: 15379
Joined: November 26th, 2007, 12:28 pm
Location: Pemberton, NJ.

Re: Speedometer drive gear 5704838

Postby m3a1 » October 22nd, 2018, 9:29 am

I believe there's also a rather large thrust washer behind that retaining bolt. If I am correct and if somebody forgot to put it back in....well....
m3a1
Colonel
Colonel
 
4 years of membership4 years of membership4 years of membership4 years of membership
 
Posts: 1430
Joined: August 7th, 2014, 5:36 pm

Re: Speedometer drive gear 5704838

Postby Fil Bonica » October 22nd, 2018, 11:08 am

Dont recall the entire reassembly after five years but the fix was good.
Still have the damaged shaft in the basement and it looks like what we see here.


Fil Bonica
K1ABW
Fil Bonica
Brigadier General
Brigadier General
 
10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership10 years of membership
 
Posts: 2457
Joined: December 9th, 2007, 9:49 am
Location: Falmouth, MA

Re: Speedometer drive gear 5704838

Postby Krempely » October 25th, 2018, 9:10 pm

Replaced the drive gear and made sure everything was put back together properly. The gear oil was in great shape for its age and wear. No sign of water contamination. Took a test drive and it functioned flawlessly; no needle bounce on the speedometer.

Next project is determining if my temp gauge or temp sending unit is out.

Thanks for all the advice and tech info.

Krempely
1964 M151
1943 MB
1952 M135
1984 M1009
Krempely
Private
Private
 
1 year of membership
 
Posts: 4
Joined: August 24th, 2017, 4:32 am


Return to Technical Discussion

Who is online

Users browsing this forum: No registered users and 4 guests

Customization by G838.org