COMBINER & RELIEF VALVE GP 8J8921 - Caterpillar

Manual Adjustment of Bulldozer Blade Pitch
Illustration 1 g03798292
Illustration 2 g02660157
Angle of cutting edge is an approximate number
(A) Nominal position - 58 degree cutting edge in the middle position.
(B) Retracted position - 56 degree cutting edge
(C) Extended position - 62 degree cutting edgeThe bulldozer blade can be placed in several pitch positions such as the following pitches: the middle position (A), the retracted position (B) and the extended position (C).
Lower the bulldozer blade to the ground. Place the control for the lift cylinder in the FLOAT position.
Actuate the tilt cylinder to remove all force from the tilt brace. Stop the engine.
Remove lock pin (1).
Keep fingers clear. Do not place your fingers into the pin holes in the tilt brace and/or push arm bracket at any time during the adjustment procedure.
Face the left-hand end of link (3) and rotate handle (2) counter-clockwise to shorten the link. This position (B) has a less aggressive cutting angle and is better with loose materials.
Face the left-hand end of link (3) and rotate handle (2) clockwise to extend the link. This position (C) has a more aggressive cutting angle and is better with tougher materials.
Turn the handle until the desired cutting angle is set.
Install locking pin (1).Power Adjustment of Bulldozer Blade Pitch (If Equipped)
The bulldozer blade can be moved into the following pitch positions with implement control lever (5), if equipped: the extended position (E) and the retracted position (F).
Illustration 3 g06003064
Some components removed for clarity
Power pitch assembly: retainer bolt (4) shown
Illustration 4 g06003082
Press button (E) to pitch the blade forward to the extended position.
Press button (F) to pitch the blade rearward to the retracted position.Note: The functions of the Power Pitch buttons with change operation if an Automatic Blade Control System is installed and turned ON. The buttons will become increment and decrement control buttons