MTFCA Forum

Unlike the NASH transmission mounted speedometer drive sold for Model T's, which used more than two gears, did the Patterson drive use only two gears, one on the transmission output shaft and one on the end of the cable which was secured to the transmission inspection cover?

The Patterson drive used a two piece bronze spiral gear fitted next to the clutch throwout. The two halves of the gear were held together by a couple of split [cotter] pins! This could be fitted as an aftermarket item, unlike the Nash drive which involved much more work to install.

If anyone has a spare tapered fibre gear that goes on the Patterson drive pickup in the transmission cover, i have a friend who needs one.

Allan from down under.

I bought a complete Patterson set up. I bid on an original installation booklet for a Patterson set up. The EBAY auction for the booklet ended last night. Unfortunately, I wasn't high bidder, so if the winner of the auction is a Forum reader, please get in touch with me. If you'd copy the booklet for me, I'll make it worth your time and effort.

Terry, this post may have what you need:

[https://www.mtfca.com/discus/messages/5 ... 1431056113]

I also have a Patterson drive setup but the pinion gear is pretty worn. Could you post pictures of your gear with some measurements?

The drive I have has a four start spiral gear and a 10 tooth fibre pinion gear which is well worn. The top right hole in the cover is round as usual. All the others are slotted. I presume this is to allow some sort of mesh adjustment between the spiral gear and the pinion.

Allan from down under.