Usage:
227 Loggers ( 10X ) Equipped With Felling And Bunching Attachments
If a feller buncher attachment from a source other than Caterpillar is installed on a 227 Logger, an 8J9974 Check Valve Group must be installed. The illustration shows locations of the 3G5838 Bank Valve Group, the 8J9974 Check Valve group and tilt cylinder in the hydraulic schematic.
The 3G5838 Bank Valve Group used in the 227 Logger controls the hydraulic oil flow to the tip and tilt cylinders. Because the tilt valve is an open-center valve, hydraulic oil can flow from the tilt cylinder in the shear head, back through the valve and into the hydraulic tank. For this reason, an 8J9974 Check Valve Group is needed between the bank valve and the tilt cylinder to prevent this return flow. If the check valve is not used, the tilt cylinder will not be able to hold its position with a load in the shear head.
If the standard feller buncher arrangement is bought with the 227 Logger, the feller lines group which is part of the arrangement has the 8J9974 Check Valve Group.
Locations of the bank valve group, the check valve group and the tilt cylinder in the hydraulic schematic for a 227 Logger.