Removing the tracks and attaching transaxles to the tracks

Now that I had some of the major pieces, I needed to see how they were going to fit together. First steps was to tear into the snowmobiles, and get the track units out. Since the motors were junk, and partially disassembled, they actually came out super easy, in fact, they weren’t even bolted in, so I lifted them out and away. Next I lifted up the rear ends, and pulled out the hardware that holds the track and suspensions into the tunnel.  Once that was loose, I needed to remove the driveshaft assembly at the front. This was the most difficult, but after a short time, that was out too. Then I was able to slide the track and suspension assembly out. Because the suspension has a shock and spring in it, it needs to have the spacing between the supports maintained, so I took two 2×4’s, drilled some holes and bolted them on. This would allow me to take some measurements and start the mockup.

Suspension Mock-up

Next I needed to join the splined end of the track driveshaft to the shaft end of the transaxle. The transaxle was setup with a 4-bolt hub, which I didn’t need, so I measured and cut off the shaft. A bit of measurement with the calipers, and lo and behold, the shaft on the transaxle and the driveshaft on the tracks were both 1” diameter!!! Some searching on the internet, and I found a place that had some large shaft couplers that needed a ¼” keyway. I ordered up 2 of those items, and a few days later, I was ready to attempt making the connection.

I clamped each driveshaft from the tracks into the vices on my vertical mill, put in a ¼” endmill, and put in a nice long keyway on each shaft. That was fairly easy, and my confidence was high! Next I carefully clamped the transaxles into the vice, and prepared to cut that keyway, and promptly burned up the endmill trying!!!! Turns out that the shaft on the transaxles were case hardened, and regular HSS endmills were not going to be up to the task! After consulting with a friend at work who’s done a lot of machining on hardened steel, he recommended a cobalt endmill. I hopped onto Enco’s website, and ordered up some cobalt endmills and some other miscellaneous items that I “needed”! Once that order arrived, I was able to try this again! What a difference a better endmill makes, in a short time, I had both keyways complete on the transaxle shafts. Next I assembled the transaxle, shaft coupler and track driveshaft together.

Suspension Mock-up

 Next >> Part 4: Start of the Frame