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Re: Speedometer - progress

To: Dean <dht3000@adelphia.net>
Subject: Re: Speedometer - progress
From: Dave & Marlene <rusd@velocitus.net>
Date: Sun, 01 Aug 2004 18:35:36 -0600
Dean,

Good for you, persistance pays off. The theory behind your problem is 
that the odometer drive "dogs" present uneven resistance to the 
speedometers rotation. It takes more force to roll over the wheel as it 
is advancing & then the resistance suddenly drops as the wheel slips 
into place. A periodic loading & unloading of the drive cable.

During the resistance phase, the drive cable winds up slightly, one end 
slows down in relation to the other, then the dog resistance decreases & 
the cable unwinds & the end of the cable speeds up slightly. The needle 
moves accordingly.

This can be caused by a worn cable & housing allowing more than the 
usual slop for wind up, or by the drive dogs meeting with more than the 
normal resistance as they turn, or both. Cleaning & lubing the "correct 
parts" of the odometer assemblies can reduce this wheel resistance.

Since you apparently have the determination & skill to proceed, the 
following web page goes into the details, nothing to loose at this 
point. Try freeing up the odometer wheels. A little lube on the main 
bearing will help also.
http://mgaguru.com/mgtech/dash/st101.htm

What ever you do, if you save the parts, a good shop such as;
Margaret Lucas
Mo Ma Manufacturing - instrument repair
13211 Second Street. NW
Albuquerque, NM 87102
Ph (505) 766-6661 - Fax (505) 766-5419
momanm@aol.com

can put things back in working order.
Good luck,

Dave Russell
BN2

Dean wrote:
> Ok I found my problem by process of elimination. I took the whole cable out
> with the sheath. Hooked it up to a drill and it ran smooth. I then hooked it
> up to the speedometer which I also took out and had it on my bench. It did
> the same thing. So I proceded to take the speedometer apart and watch it as
> I ran the drill . I could see it hesitating. I then tried lube  but that
> didnt help. I noticed that when it changed the digits for the mileage was
> when it hesitated. So I took off the dogs that drive the digiatal numbers
> and walla. Its smooths as a babys butt. I don't know if I can fix that part
> of it  though. But I definitaly  located the area of my problem.
> 
> Dean





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