Author Topic: Reverse problem-AGAIN  (Read 458 times)

Offline Fred Mc

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Reverse problem-AGAIN
« on: September 25, 2017, 05:44:37 PM »
I couple of weeks ago I had a problem engaging reverse in my GMPD4106. So I took it apart, cleaned it and adjusted the linkage. It worked fine. Or so I thought.
What happens is it works fine when the engine is cold(i.e. in the yard or leaving the campsite) but when the engine is at operating temps it won't engage. This past week I had to disconnect the linkage for the solenoid and have my wife push in the lever  while I shifted into reverse(I'll make her into a mechanic yet LOL)

Oddly enough in the wiring diagram in the manual  it shows the reverse relay with a connection to #3 circuit breaker and a notation that says "hot bus"Any connection  or is that just an electrical term.

Offline chessie4905

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Re: Reverse problem-AGAIN
« Reply #1 on: September 25, 2017, 07:14:42 PM »
Hot electrical bus connection even with key off. Bus is also an electrical term. Make sure you are getting full voltage to solenoid and points open as I described several posts ago.. Could be a bad solenoid btw. Mine acted the same way till I properly adjusted the play in the linkage, even with a new solenoid. Apparently the solenoid needs that free play to start moving to pull lever. The momentum assists it to do its job.
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Online bevans6

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Re: Reverse problem-AGAIN
« Reply #2 on: September 25, 2017, 07:36:43 PM »
I also had a problem with reverse when I adjusted the slack out of the mechanical levers.
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia