Usage:
Introduction
This Special Instruction provides the necessary information for the adjustment of Cab Door Latch Assemblies and Strikers. See the chart for Covered Latch Assemblies and Strikers. Also provided, are the necessary maintenance instructions for the latches.
NOTE: Both the Standard Duty and Extreme Service cab door latches and strikers are covered by these adjustment instructions.
Do not perform any procedure, outlined in this publication, or order any parts until you read and understand the information contained within.
Reference: Parts Manual
Adjustment Procedure
Standard Duty
(A) Primary position (fully latched). (B) Unlatched position. (C) Lubricate with a dry type lubricant.
Extreme Service
(A) Primary position (fully latched). (B) Unlatched position. (C) Lubricate with a dry type lubricant.
1. Close the door and locate striker (1) in latch assembly (2) so it is centered vertically in the latch pawls, engages the pawls smoothly, and does not guide the door upward or downward.
2. Check for interference between striker head and pawls or latch case. Adjust striker, if required, by adding or removing 8T0318 Striker Shims.
3. Check latch pawls to confirm they are in the primary latch position. When in primary position (A), the door is fully closed and latched. In the secondary latched position, the door is latched but the pawls are not in the primary latch position.
4. If primary position (A) is not achieved due to high seal pressure or striker position, loosen striker on door post and adjust striker until primary latch position is achieved. Tighten striker (1) to a torque of 45 ± 7 N·m (33 ± 5 lb ft).
- * Hinge adjustment may also be required to achieve primary position or correct door seal pressure.
- * Excessive seal pressure results in high handle opening torque loads.
NOTE: It is possible to adjust the door so that it is fully closed against the seal with the latch in the secondary position.
NOTE: On Some D9N, D10N, and D11N Tractor cabs, additional striker adjustment may be necessary to allow the door to be correctly adjusted. To provide additional striker adjustment, the mounting hole for the striker may be slotted toward the centerline of the cab. The maximum dimension allowed is 40.3 mm (1.59 in). See Illustration 2.
Illustration 2. (D) Std. - 35.3 mm (1.39 in). (E) Max. - 40.3 mm (1.59 in). (F) 20.5 mm (.81 in) diameter. (G) Cab post. (H) Centerline of cab.
Maintenance
Use an air dry type lubricant that is spray applied for maintenance in latch component areas (C). This maintains smooth operation of the linkage. (Dry lubricant reference: PERMA-SILK® or MOLYKOTE 321®).
- * The use of a wet type lubricant is not recommended due to the grit build-up it causes.