Do you have a Standard of HI Capacity reverser.
Do this if you use that head.
IMPORTANT: After greasing, cycle the variable from low to high speed a few times to distribute the grease inside the gearcase.
Note: Run the feederhouse variable to high speed, (sheaves apart). In this position the cam cavity will be the smallest, Caution: Greasing with sheaves together (low speed-larger cam cavity) could cause the seal to be blown out. With sheave turned so zerks are in the 12 o'clock and 2 o'clock positions see 5877.jpg, the zerk at 12 o'clock provides grease to the cam cavity, and the zerk at 2 o'clock provides grease to the inner cam surface and grease seal. The zerk at 12 o'clock can take additional grease (5-8 pumps every ten hours). Grease will purge out under the tension spring. Use TY6341 or TY25744 Greases Only. Other types of grease will dry out and become hard making them ineffective. Grease at least once a day (more if yield is above 200 bu/ac) with TY6341 or TY25744. Cycle the variable each time after greasing.
TY6341 and TY25744 greases are the only approved greases for the variable drive system. If any other type of grease (other than TY6341 and TY25744) have been used: Disassemble the cams, clean out all evidence of whatever type of grease that is currently there and start over using TY6341 or TY25744. Inspect the cams for rust, burrs and for galling. This is usually caused by the lack of lubrication. Replace as required.
Check to ensure that the backshaft speed range is 520 to 780 rpm with no load at high idle. If there is more than a 20-rpm difference in either the high or low speed, readjustment is required. Run the variable to slow speed 520 rpm, stop the machine and measure the sheave gap. It MUST be 1/8" (3mm). If the gap is more than 1/16" off, readjustment is required. Sheave gap must be maintained at 1/8" ± 1/16” (3mm).
IMPORTANT: Move the upper variable to the rear as much as possible to obtain the sheave gap. This method will allow the idler pulley to be as low as possible thereby providing maximum belt wrap while still maintaining the 3MM sheave gap. See OM for the details.
Sheave Gap Adjustment
1.) Move the idler (A) down to the bottom of the slot. DO NOT stand on belt then push idler up to set gap.
2.) Next move the upper variable to the rear as much as possible using adjusting bolt (B) to obtain the 3 mm (1/8”) sheave gap. This method will allow the idler pulley to be as low as possible thereby providing maximum belt wrap.
3.) Check upper drive sheave, it must run parallel with side sheets of the feederhouse. Look at upper, outer sheave for burnt or black marks. This is a sign of the sheave running crooked.
4.) Adjust idler to remove slack from belt.
5.) Run the variable through its speed range at high engine idle, from low to high and make sure the backshaft speed is 520 to 780. If there is more than ± 20 rpm difference in either high or low speed, readjustment is necessary.
At this time also inspect the idler bracket for bending and or cracking. A new, stronger idler bracket is available. Replace with AH205618.
During harvest, run the backshaft at a faster speed. Running faster backshaft speed reduces the torque loads, which results in lower heat levels, which can cause less belt slippage. This also increases the torque sensing efficiency for the belt drive resulting in less belt slippage and more heat transfer. This may require slowing the corn head down to under drive or the 1:1 drive ratio in order to maintain desired ground speed.
Check the movement of the cams in the reverser. Run the variable drive to the high end (780 rpm) and let it run there for 10 to 15 seconds. Stop the combine and make two timing marks exactly across form one another on the reverser sheaves. Now run the variable again and lower the speed all the way to the slow speed (520 rpm) and let it run at this speed for a few seconds. stop the combine and check the position of the timing marks. They should have moved approximately 3/8" (9mm) or more apart, depending on the type of drive. if they did, the cams are working properly. If they did not move apart, the cams are likely locked up. Check cam-mating angles for burrs, nicks or something that is preventing them from moving. Refer to Technical Manual (Diagnostics and Test) to make sure there is proper oil flow from pump to cooler and back to the pump. This should be at least 1.7 gpm at 640 rpm backshaft speed.