Speedometer gears, replacement.

[william curry]

My speedometer gave out.

My mechanic told me that there were 2 parts that were worn out.

One of them is about 3" long with a small plastic gear at one end. I will call this the pencil gear.

The other part is a drive gear that fits in the front axle "pumpkin" housing.

The pencil gear meshes with the drive gear, and the pencil gear connects with the speedometer cable.

I bought a new pencil gear, and a new drive gear. One part from one Pinz dealer, and the other part from a different dealer.

Both parts were new. Pinzgauer boxed and wrapped.

My mechanic put the new parts back together, and test drove it. After a few hundred yards the speedometer failed.

My mechanic reports that after inspection the gears barely engage, and that my new pencil gear is ruined.

What is my problem?

Is there some adjustment that can be made so as to change the depth of gear engagement?

My mechanic says no adjustment possible.

Defective parts from Pinz? I doubt it.

Help!

[ExpeditionImports]

Did your mechanic verify that the cable had no restrictions/and or the 90 degree speedo drive/and or the speedo itself? If something on the upstream side of the "pencil gear" is bad, it is quite common for it to destroy the pencil gear.

Cheers,

Scott

[william curry]

Dear Scott;

You have asked a very good question.

I bought a replacement MPH speedometer ( macho yellow faced ) from Cold War.

My mechanic put the new one in, and it quit working after 100 miles.

I just ignored the problem, and untill now have been happy to drive at zero MPH, and get zero MPG.

My mechanic said the gears were bad.

I will check with him, but from what I remember, he said that the cable to the speedometer and everything else was working without any binding in the system.

I will check with him to make "double sure" that the upstream isn't causing the gears to "jump".

I appreciate your suggestion.

I can use all the help I can get.

Thanks again.

[lindenengineering]

William
Just a couple of comments to add to Scot's input.

If the drive gear 'walks' off the diff input shaft it will sheer the teeth. The gear must be flush with the end of the shaft and retained by
Loctite.

If the holder of the pencil gear as (you call it) isn't pushed all the way down into the end case and the CORRECT groove utilized for the retaining pin, the excess end float induced will also cause tooth distress and eventual sheer.

I have seen both of these problems as well as excessive play in the diff input shaft causing the shaft to do the samba and break the teeth.
Food for thought!
Dennis