08-14-2026, 09:34 PM
i too have seen this on machines when taking them apart for various reasons. another place is the lower fan drive shaft pulley, sometimes on upper pulley as well. people always want to try and get better belt alignment on the lower belt, and move that pulley.
Another issue with the tail rotor pulley is some will have trouble getting the pulley where they want it on the shaft. So they file, grind, do something to the pulley to get it on there. They do such a poor job of this that the pulley then wobbles on the shaft under load.
for years this pulley came from the factory with a real good fit to the shaft, but it required a small amount of heat and a little oil to get it on there . If you did that it was a perfect fit. Same was true with the lower pulley on the secondary that drives the tailrotor. These came with the pulley already on the shaft from the factory and needed to be removed during the build. Always a good ideas to use a little antiseize on these aluminum pulleys.
Another issue with the tail rotor pulley is some will have trouble getting the pulley where they want it on the shaft. So they file, grind, do something to the pulley to get it on there. They do such a poor job of this that the pulley then wobbles on the shaft under load.
for years this pulley came from the factory with a real good fit to the shaft, but it required a small amount of heat and a little oil to get it on there . If you did that it was a perfect fit. Same was true with the lower pulley on the secondary that drives the tailrotor. These came with the pulley already on the shaft from the factory and needed to be removed during the build. Always a good ideas to use a little antiseize on these aluminum pulleys.