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Speedometer Pinion

jhorton3

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I got to the bottom of the speedometer problem. The issue was with the nylon gear on the speedometer pinion inside the transmission. If you haven't taken one of these off with the gearbox in the car you might want to drain the gearbox first. Otherwise most of the oil comes out the hole the nylon housing leaves behind. To take the housing off I had to use a 1 1/8" socket. There's some casting bit on the transmission that prevented me from using an open end box wrench or crescent. Too lazy to get the dremel tool out and grind it off.

Once the housing is off the pinion can be pulled out. It's nothing more than a steel shaft with a hole in one end for the speedometer cable square, and a nylon gear about 85% up the shaft. All but two teeth of mine had 4 distinct groves ground into them. Two teeth were broken clean off. Buying replacements are not cheap. So far $64 is about the cheapest I've found. Compared to a speeding ticket though, I guess it's not a bad deal.

With all the gearbox oil out I finally got the chance to put another type in there. I used Castrol HD 40 in it with a little bit of Lucas Oil Additive. I took it on a 15 mile with the new oil. The box is still noisy but shifting is much smoother. I didn't have one problem going from 2nd to 3rd as I normally do.
 
When I was going though my boxes of tranny parts for Jack I came across a couple of those. If you haven't ordered it yet let me know and I'll check the condition.
 
I haven't sent the order in, so yes if you have one in good condition I'd be interested.
 
Another alternative is a digital speedo using a Sigma Cyclometer. I adapted one for Bugsy, and now that I've got all the bugs worked out is fabulous.
 
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