440 Tripper Arm Gear Repeatedly Breaking After Replacement.
Last Updated: 10/23/2013
Why Does Tripper Arm Gear Keep Breaking
Repeated failure of the Tripper Arm Gear ( and /or the # 7 gear that drives it ), is caused by the timer assembly "binding" internally.
The gears get "sloppy" over time, and the # 8 drive gear will start rubbing against the Output Gear center hub.
This added pressure makes the already difficulty job of the Tripper Arm Gear impossible.
It's pushing the Skipper Wheel, which in turn is pushing on the "tab" of the Output Gear, and the Camshaft must also be turned a little, before the Output Gear "catches" the Drive Gear # 8, and the motor turns moving everything.
It's very common problem as the 440 timer "ages", and best solved by complete replacement of the Timer Assembly with the newer 460TC ( the current replacement for all 440 series timers ).
Common Gears that fail
Also the "Out Put Connector" # 21E ( 1031496 ) which which attaches to and drives the Cam Shaft can crack or break. On rare occasions the Camshaft # 21F-3 ( 1031950 ) will break at one end. Also, rare is a cracked Skipper Wheel # 14F-6 ( 1031740 ). Close examination of both sides of the Skipper Wheel is required to detect this failure. And last, but not least, you can have a gear post break in the housing body it's self. But only the back plates for the 440i version is available and not the "box" used with the older 440 version. It is simpler and prudent to replace the Complete Timer Assembly ( with the new 440iHV ) at this point.
The newest replacement timer is the 460TC ( runs on 12 volts ),
And now available for Models 255,263 and 268 is the Logix 740 upgrade timer kit ( does NOT work with the older 155, 163, or 168 valves... sorry ).