Your making good progress!

Back in the 80's when a Deere was my main sled, I used marine grease that you would use on boat trailer bearings. Now I just use the Ski Doo waterproof suspension grease because that is what is in my snowmobile grease gun. You can still use the boat grease. You should be able to find it at Wal Mart ...

Welcome! I always just pulled them every year, clean off the old grease, and coat them with fresh waterproof grease. Then put them back in. Good thing you are doing this. They are a real pain to get out if they were not greased every year! If not done, then the suspension arm pivots on the bolt that...

Glad you got it figured out!

That does not look right. It should be closer to what the bottom shaft/gear looks like. That is just not enough shaft in the gear. When I had to replace my jackshaft many years ago, I had to add more shims behind the gear. The new shaft was a little longer than the factory one. The big thing is that...

+2 on what Nick said.

Thanks, I did not know that. I just looked at the parts book and see that the part numbers are different between the 80 and 81 serial numbers for the sportfire. I will have to go out and measure the extra tracks that I have. I have both an 80 and 82 cleated track to see how much difference there is.

The 81-84 Trailfires used the same track as the 1980. The 81 Sportfire did also. The Sportfire switched over to the Liquifire suspension and track in 82. This will help with your search a little.

Welcome! Yea, the start of that vin does not sound right. The 78 should have more colorful decals on the hood. The pre 78's used silver decals. I think the 78 340 also had the bigger air inlet in the hood like the 440 did. The pre 78's did not have the bigger air inlet. Here is the info on your Liqu...

The locking collar goes over the flange on the bearing. You turn the collar until it locks on the flange. Then turn the set screw in the collar in until it is tight. The collar is off set a little. This is what locks the bearing to the driveshaft. Someone could have changed out the drive shaft beari...

The bearing on the speedometer side has the flange pointed inward like the second picture. There should be a locking collar on this one also. They originally did not have one on the 79-81 sleds. After a bunch of miles, the drive shaft was worn because the bearing was not tight on the shaft. Deere ad...

Looks Great!!

First off Welcome! With a sled this old, I would replace the crank seals first off. These engines are well known to need them. I had to replace the ones on my 1980 after 10 years of use. The hard starting is a good sign of this. Did you replace the carb jets for the elevation you are riding in? Othe...

You will want to remove the fan pully off the flywheel and also the shroud that had the fan in it.

I still see them every now and then on E Bay. Some dealers had them back in the day. But that one looks like an reproduction E Bay one.