Combines Maintaining rotor speed

Often the rotor belt tension adjustment (threaded rod) needs to be drawn up a bit. The tighter this adjustment, the less the variable speed sheave needs to travel to stop belt slippage. Even though your belt may not be slipping under load, it is the travel that changes r.p.m. The ratio is changing between the driven and driving sheaves as the load increases. It is likely the ratio change that is giving you the excessive drop in rotor speed. I set mine so there is less than 80 r.p.m. drop under load. For additional tips on the combine, click on the TIPS button to the left and fill out the form and I'll mail it to you.

Our 2188 had to have the torque sensing spring replaced last season due to loss of compression, we installed what they called a 500 lb spring out of a 2388. Hope this helps.

We replaced the whole torque sensor assembly on our 1680 with the unit for a 2388. It works great. I can't remember exactly how many RPM's we loose now, but it is much less than we used to loose. The PN is B92768A.