Loose Throttle Setting

Hi Folks,
George's 39Y has developed a new issue in that after setting the throttle at 2450 it backs off to 1800 RPM's as the throttle slides back. Is there an adjustment we can make to increase throttle lock.
Thanks
John

Take your throttle panel off and tighten the nut. There should be friction washers in there.

Thanks Alan,
Is the friction lock on both front and rear? I heard you were doing some angle of incidence readings on your SC over the weekend. We were doing the same over at Cranland to get MD her thrustline this coming week.
John

Flying Miss Daisy said:

Thanks Alan,
Is the friction lock on both front and rear? I heard you were doing some angle of incidence readings on your SC over the weekend. We were doing the same over at Cranland to get MD her thrustline this coming week.
John

Click to expand...

John-

You can just do the front one to where you like it, they are inter-connected anyway.

Tim

Shouldn't the RPM's creep up instead of down?

Lawn Dart said:

Shouldn't the RPM's creep up instead of down?

Click to expand...

Depends if you have spring on your throttle arm. Not likly though since if the actual throttle cable breaks you can always push it forward, not back. If the fitting at the end breaks...

You can buy the fiber replacement washers from Univair, however I have had great results for PA 12's throttle by taking a razor and spliting a rubber grommet in half and using it as a friction inducing part. The half of grommet fits nicely inside the concave washer retainer. A little grease and a washer and you can adjust it to be as smooth and as resistant to slip as you like. My 12 had leather washers that were well past there prime, but the fiber washers provided per the parts book worked as well. I like the rubber grommet because it gives the throttle a slightly improved feel and smoothness. The assembly uses a castlated nut for friction adjustment. I would do both the front and the rear. It will work like new.