PDF Instructions for replacing the 41872R.S Chain/Belt Adjustment screw
41872R.S Chain/Belt Adjustment Screw Replacement:
This repair will require removal of the unit from it’s mounting hardware and repair made on a bench or floor. Refer to the Owners Manual or Installation Poster for proper assembly and carefully read and understand all warnings and cautions pertaining to this unit.
BE SURE ELECTRICAL POWER HAS BEEN DISCONNECTED FROM THE OPENER PRIOR TO REMOVING THE MOTOR COVER. !
ANY AND ALL REPAIRS MADE TO THIS UNIT MUST BE PERFORMED WITH THE DOOR DISCONNECTED FROM THE OPENER AND IN THE CLOSED POSITION.
Follow these steps for replacement.
1. Unplug opener power cord from power receptacle or turn off breaker.
2. Close Door. (If unable to lower door using opener, use extreme caution manually closing door. Before pulling emergency release cord, make certain people and objects are clear of door opening.) Pull emergency release cord down until it latches to close door manually.
3. Unplug Battery Backup (BBU) (if equipped) from top of powerhead. FIG. 1.
4. Remove clevis pin attaching the door arms to carriage. FIG. 2.
5. Remove opener from mounting hardware. Refer to owners manual or installation poster.
6. Remove rail assembly from powerhead. FIG. 3.
7. Remove damaged adjustment screws from belt/chain assembly with master links. FIG. 4
8. Install GOLD colored adjustment screw assembly onto door side of belt/chain with master link. FIG. 4/5.
9. Install SILVER colored adjustment screw assembly onto opener side of belt/chain with master link. FIG. 4/6.
10. . Install turnbuckle onto GOLD colored side. Rotate 1 full turn. FIG. 5.
11. Feed turnbuckle through carriage assembly. FIG. 6.
12. Install SILVER colored adjustment screw assembly into turnbuckle. Rotate 1 full turn. FIG. 7.
13. Pull belt/chain and carriage assembly to middle of rail assembly. FIG. 7.
14. Tighten belt/chain as shown in FIG. 8 & 9.
- Hold chain/belt and rotate turnbuckle with thumbs counter-clockwise until chain/belt is tensioned properly. Measure chain/belt tension on opposite side of rail until 1/4” from bottom of rail.
15. Once belt/chain is properly adjusted, tighten lock nuts to turnbuckle. FIG. 10.
16. Install rail assembly onto powerhead. Reverse STEP 6.
17. Install opener assembly to garage as removed in STEP. 5.
18. Attach door arms to carriage assembly. Reverse STEP 4.
19. Manually open door until carriage assembly locks into turnbuckle.
20. Plug BBU into harness at top of opener (if applicable). Reverse STEP 3.
21. Apply power to opener.
22. Reset limits per owners manual.
23. . Perform safety check to ensure door will reverse off of a 2x4 layed flat in middle of door. Refer to owners manual.