Flap motor intermittent failure - grounding?

[dsmithlib]

I have an RV7 with 170hrs. On two or three occasions, I have reached for the flaps and get nothing. I have never been stuck with flaps down needing to lift off so I am grateful for that.

On the first failure read everything and dug in an disassembled the motor, cleaned the grease, and removed an in-line molex disconnect. It worked Months later - the second time I started taking the covers off, rattled the motor lightly by hand, tested again and flaps worked - so I closed up with a declared success.

More moths later - I encountered problem again and embarked on the third attempt to fix this. Once I removed the cover and rattled the motor by hand, it came to life. This leads me to believe that I have a ground problem at the motor.

My wiring consists of hot and ground through the B&C toggle switch. I believe the switch effectively flip flops the wires to result in up or down operation of the motor. Most importantly, I believe that all required grounding is coming through these wires AND NO LOCAL GROUND AT THE MOTOR IS REQUIRED.

Is this correct? or is a local ground to the case on the flap motor required? Because this motor comes to life each time I rattle it, I am thinking that a local ground must be required.

I cannot find anything that specifies that the motor should be grounded locally. However, my diagnostics have led me to believe that each time I put slight pressure on the case, it seems to reestablish its ground.

I am planning to attach a local ground to the motor case. However, I thought I should check in with others to see if I embarking on some voodoo solution.
Thanks,
Dave Smith

[Walt]

A "local" ground is not required and will not help. The motor windings are isolated from the case, power and ground are supplied through the switch. Chances are jiggling the motor is causing the brushes to make contact with the armature.

[Bob Martin]

When mine went bad some years ago, I replaced it and have not had a problem since....knock wood.

[Tim 8-A]

Check the brushes, I had a crack in one of my brushes and the motor would intermittently quit working.

[868RM]

Dave, I had to clean the brushes & armature twice in first 20 hours. They would get enough grease on them to loose contact. Have not had any problems in 100 hours since. Ron