[TR] Eratic Speedometer

[Allen Hess]

The cable spins a magnetic bar which spins a shallow metal cup (no  
physical connection) to which the needle is attached. I discovered  
that the magnet touched the edge of the cup at one point and that  
caused the needle to jump. Also noted that the bearing point of the  
cup and needle axle was worn which didn't help. The cup is light  
weight metal and can be bent enough to eliminate the contact.

Allen
On Mar 16, 2012, at 12:24 PM, triumphs-request at autox.team.net wrote:

> Subject: [TR] Erratic Speedometer
>
> My TR3 speedometer  whips at low speed, steadies out mid range and  
> then
> becomes erratic around 60 mph. I replaced the cable, routed it  
> exactly same
> way as the original , but the problem remained. I suspect it is  
> still a
> cable problem.
> I read somewhere that lubricating with oil or other liquid is bad as  
> the
> factory carbon lubricant may migrate with it upwards into the  
> speedometer
> bearings which is harmful in the long run.
> Is the speedometer the more likely culprit? Has anyone serviced one?
> Could lack of damping with age be a problem?
>
> Hans, 61TR3A