mopowers
Well-Known Member
Just wanted to post this as an FYI for folks. I learned this from a local speedometer shop owner. He was one of those old guys who have been in the business forever. He even gave me an extra shaft to play with. I was having trouble finding a reasonably priced 37 tooth long shaft gear and he didn't have any in stock. But he did have a 37 tooth short shaft gear and explained how easy it is to swap shafts. Here's how I did it:
Short shaft 37 tooth gear. $15 from speedometer guy
I set it up in a bench vise with a 3/8 deep socket to support the gear and a 16 penny sinker to push the shaft out. After I set it up I warmed the plastic up gently with a heat gun then proceeded to press the shaft out. Just make sure the plastic gear is supported close to the shaft or it'll deform or break the bottom of the gear.
Here's the gear with short shaft that was pressed out and the tools used.
Gear with the long shaft to be pressed on:
Pressed the long shaft in it's place. The guy at the speedometer shop said he has done this for a long time and has never seen the gear slip because of the knurl on the shaft, so no epoxy is necessary. I suppose you could use some sort of adhesive if you want to. Warming the gear gently with a heat gun doesn't hurt either.
All the parts and pieces used as well as a stock 35 tooth gear for reference.
Hopefully this helps folks having trouble finding the speedometer gear they need for a decent price. Screw spending $80 on a hard to find speedometer gear.
Short shaft 37 tooth gear. $15 from speedometer guy
I set it up in a bench vise with a 3/8 deep socket to support the gear and a 16 penny sinker to push the shaft out. After I set it up I warmed the plastic up gently with a heat gun then proceeded to press the shaft out. Just make sure the plastic gear is supported close to the shaft or it'll deform or break the bottom of the gear.
Here's the gear with short shaft that was pressed out and the tools used.
Gear with the long shaft to be pressed on:
Pressed the long shaft in it's place. The guy at the speedometer shop said he has done this for a long time and has never seen the gear slip because of the knurl on the shaft, so no epoxy is necessary. I suppose you could use some sort of adhesive if you want to. Warming the gear gently with a heat gun doesn't hurt either.
All the parts and pieces used as well as a stock 35 tooth gear for reference.
Hopefully this helps folks having trouble finding the speedometer gear they need for a decent price. Screw spending $80 on a hard to find speedometer gear.
