Re: Has anyone here ran a 9670sts with a 612c chop
Yes it can work. Hope you have the High Torque Variable Speed Feederhouse Drive.
High horsepower requirements, high yielding crop, chopping cornheads, tough green corn stalks along with improper sheave gap adjustments and improper maintenance can lead to both of the complaints above.
Guide For Improving Feeder House Variable Drive Performance
There are three basic types of Feederhouse Variable Drives still in production today: the Standard Variable drive, the Heavy Duty Variable drive and the High Torque Variable drive.
Standard Variable
The Standard Variable has no oil cooler, a single belt at the electric clutch, and the back of the feeder house belt is smooth, and it is mostly on smaller and older combines. This was the only drive on 10 Series and earlier.
Heavy Duty Variable
The Heavy Duty Variable has an oil cooler, a double belt at the electric clutch, and the back of the feederhouse belt has small cogs. This drive started production with 50 Series. The return oil hose is the indication of the High Capacity Drive. see graphic
High Torque Variable
The High Torque Variable drive also has an oil cooler, a double belt at the electric clutch, but the top of the variable drive belt has large cogs like on the bottom. The gearbox is much larger, and the sheave is locked on with a large nut. This drive started production during 60 Series in 2006. (715100 - ).
Proper lubrication of the cams is one of the most important things you can do to ensure the feederhouse drive is working properly. The Operator's Manual recommendation is: When operating in severe conditions or high yielding corn, grease each fitting 3 - 5 pumps every 10 hours.
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.
Note: Discourage from using less expensive or other types of grease. 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.
Inspect outer , upper variable sheave, If it is black from heat the upper sheaves must be realigned making sure they are parallel with the Feeder House side sheet.
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). see graphic
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.
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.
Oil: Testing has shown that there is some benefit from using synthetic oil. These oils will run a few degrees cooler, but the difference is insignificant. The major advantage is that they will not break down as fast as conventional oil in heavy load conditions. Synthetic oil will run longer and hotter without turning black from oxidation. A second major benefit of using synthetic oil is it will have less change in viscosity in cold weather, enabling the oil cooler pump to circulate oil more efficiently. If you choose to install synthetic oil in the feederhouse reverser, John Deere currently offers synthetic oil, TY26408. Starting with 70 Series combines, all feederhouse reverser gearboxes are factory filled with synthetic gear oil in place of 80W90. This oil can be used in reverser gearboxes on 60 Series and prior models.
The reverser gearcase oil capacity is: listed in the Operator’s Manual. Because of heat generated from the variable sheaves, the amount of airflow over the cooler, ambient temperature, various sizes of headers and crop conditions, the effectiveness of the cooler can vary greatly.
Note: In some cases the addition of a second cooler has resulted in satisfactory operation.
Note: Mixing of greater then one cup of synthetic oil, TY26408, and 80W90 is not recommended. If the 80W90 oil has been drained for service, you can refill with TY26408 without having to flush the gearcase. Also make sure to drain the cooler and lines before refilling with synthetic.
Grease: John Deere offers TY25744 John Deere Extreme Duty Synthetic Grease.
This grease is Non-toxic, food grade, and biodegradable. It is translucent white in color. It has an operating temperature range of -45 deg. F to +450 deg. F. The grease thickener is fumed silica which is a synthetic thickener. The lubricating media of the grease is a combination of synthetic oil and PTFE (Teflon) particles held in suspension. The Extreme Pressure test performance of TY25744 is 80% of that for TY6341, however the load wear index (which defines the overall EP performance) for TY25744 is 180% that of TY6341. Our conclusion from this is that the EP performance of TY25744 is as good as or better than that for TY6341.
Compatibility testing has shown that TY25744 can be used as relube for a unit already filled with TY6341 without concern of any serious consequences.
Based on the above information our conclusion is that for this application TY25744 is as good as or better than TY6341 in the torque sensing feeder house drive application. We would recommend it to customers running with high feeder house drive load levels as providing a potential improvement in performance of the variable belt drive. We recommend following the 10hr lube interval with 2 to 3 pumps for each zerk on the torque sensing unit.