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440 Tripper Arm Gear Repeatedly Breaking After Replacement.
Last Updated: 05/12/2016

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 a 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

  1. Tripper Arm Wheel # 99F ( 1031756 ) *Most COmmon Gear to break at the 2-3am Position
  2. # 7 Black Gear # 420A43 ( 1031554 ) *Gear that drives teh Tripper Arm Gear and oten strips out at the same time as the Tripper Arm Gear Breaks
  3. Red Knob Gear # 106H ( 1001582 ) * now "Black" closely examine the "over hang" teeth of the OUT PUT GEAR as they sometimes snap off
  4. # 8 Black Gear # 420A44 ( 1030844 ) * Drives the Out Put Gear and if Stripped you can easily see this

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.

A complete replacement is also prudent if the unit is over 20 years old. See: 440 Replacement Timer Assembly 440iHV w/Cord

The newest replacement timer is the 460TC ( runs on 12 volts ),
see:The 460TC replaces all previous 440 Timer Assemblies.

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 ).

See for 255 valves: Upgrade Kit 255/740 Logix Electronic Replacing 440 Series Timer Upgrade Kit 255/740 Logix Electronic Replacing 440 Series Timer

and for Performa 263 or 268: Upgrade Kit Perfoma 740 Logix Electronic Replacing 440i Series Timer Upgrade Kit Perfoma 740 Logix Electronic Replacing 440i Series Timer

A complete replacement is also prudent if the unit is over 20 years old.

you might want to look at the Newest Option
Which replace the 440iHV .... is the -

Complete 460TC ( timer clock ... NOT metered ) with 12 volt transformer

for use with 120 volt 60 hz installations
Uses Electronic 7 Day programmed timer ( will regenerate on the DAYS you SET )
The 460TC replaces all previous 440 Timer Asjavascript:void(0);semblies.

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