RV-6 Flap Actuator

[rvsxer]

I have 1400 hours on my 1999 vintage flap actuator and somehow missed out on the problems others have had. Now, when I lower the flaps past about 1/3 at approach speed they slow and make a groaning sound, like the motor is laboring a little. They still extend all the way (at least for now). Has anyone rebuilt one of these? I am planning on swapping the motor for a new updated one but do I need to worry about the overrunning clutch or the jackscrew? I have searched and found a lot about the motors but nothing about the rest.

[Bob Martin]

Check the SB on Vans site.
To comply you replace entire assembly.
Pricey but all new.
I just did it.

[az_gila]

Originally Posted by Bob Martin

Check the SB on Vans site.
To comply you replace entire assembly.
Pricey but all new.
I just did it.

The only SB that calls for replacement is this one. Easy to see if you have the cross-drilled holes or not -

http://vansaircraft.com/pdf/sb04-3-1.pdf
http://vansaircraft.com/pdf/sb96-10-3.pdf

The other SB calls for safetying the lower fitting -

http://vansaircraft.com/pdf/sb07-4-12.pdf

Did I miss any?

[JonJay]

I suspect your motor is binding as a result of the actuator not being lubricated adequately anymore. I have not needed to do this, but if you do investigate and find that they can and do need to be greased up, make sure you don't overdo it. Grease can foul the motor brushes as noted in the SB.
The other possibility is the bushings are just plain worn out. Perhaps some high time airplane owners like Rosie can chime in? Seems a bit early for these to be worn out, but if they where under greased originally, maybe.
Scott?

[Bob Martin]

Originally Posted by az_gila

The only SB that calls for replacement is this one. Easy to see if you have the cross-drilled holes or not -

http://vansaircraft.com/pdf/sb04-3-1.pdf
http://vansaircraft.com/pdf/sb96-10-3.pdf

The other SB calls for safetying the lower fitting -

http://vansaircraft.com/pdf/sb07-4-12.pdf

Did I miss any?

Gil.
those are the ones ....
the cross drilled SB actually replaces the whole assembly.
that was my point.
thanks for links.

[Pat Hatch]

Originally Posted by rvsxer

I have 1400 hours on my 1999 vintage flap actuator and somehow missed out on the problems others have had. Now, when I lower the flaps past about 1/3 at approach speed they slow and make a groaning sound, like the motor is laboring a little. They still extend all the way (at least for now). Has anyone rebuilt one of these? I am planning on swapping the motor for a new updated one but do I need to worry about the overrunning clutch or the jackscrew? I have searched and found a lot about the motors but nothing about the rest.

Mike, one other thing to check is to make sure there's no binding anywhere in the flap actuator mechanism. I disconnect the flap electrical actuator from the actuator arm and make sure you can move the flaps by hand though the entire range of motion. Also make sure your rod end has SB 7-4-12 complied with.

[az_gila]

Originally Posted by Bob Martin

Gil.
those are the ones ....
the cross drilled SB actually replaces the whole assembly.
that was my point.
thanks for links.

Yes... but my point was it has nothing to do with the motor running slow or making funny noises, like the OP states...

PS... I had a cross-drilled one and found the 2004 discount offer has run out...

[rvsxer]

Thanks for all the replies! I don't have the cross-drilled actuator. Time to open it up and see what's going on in there...

[Doug]

As other have said check for binding through the full range. I discovered an over long #8 actuator cover panel screw was contacting the mechanism. The motor had sufficient power and mechanical advantage to overcome the resistance but caused some strain on the motor and mechanism.

[Rosie]

Originally Posted by JonJay

I suspect your motor is binding as a result of the actuator not being lubricated adequately anymore. I have not needed to do this, but if you do investigate and find that they can and do need to be greased up, make sure you don't overdo it. Grease can foul the motor brushes as noted in the SB.
The other possibility is the bushings are just plain worn out. Perhaps some high time airplane owners like Rosie can chime in? Seems a bit early for these to be worn out, but if they where under greased originally, maybe.
Scott?

Thanks for the callout.... I'm 10 hours short of 4200TT on the flap motor, and I've replaced my brushes twice. I've not had ANY problems, and I spray LPS #1 on the flap rod at every annual Rosie