Trim motor adjustment

[Jim]

I am doing the initial adjustment on my electric trim. I set the 7/16 inch clearance called for in the manual. I then run the unit all the way down. When I run it back up it goes past the 7/16 inch setting and hits the tube above. Do I have a bad unit or am I missing something in my adjustment procedure? Thanks for any input.

Jim
Series 5 0-200
21D MN

[Dorsal]

Jim,
I pretty sure you are missing an adjustment step, I don't have my manuals handy but if someone else does not chime in sooner I will follow up over the weekend.

[jtpitkin06]

OK... chiming in....

The adjustment is fairly simple.


Mark the slide block guide tube at 7/16 inches down from the top. This will be your upper limit of stabilator travel.


Next, measure the total jack screw travel. Apply power to the stabilator jack screw to run it full travel in both directions. It should move a total of 4-1/2 inches. If it moves more, then maybe you have too much travel. The airframe can handle about 5 inch max.



Apply power to run the jack screw to maximum length for mounting.


Mount the jack screw at the bottom.



Adjust the rod-end at the top of the jack screw to position the stab at the 7/16 mark. Tighten the lock nut.



Hold or pin the scissor links while you run the jack screw up and down under power. It should stop at your 7/16 mark on the upstroke and stop at 4-15/16 on the down stroke.


If the jack screw stops at your upper limit, attach the scissor links as directed. If not, adjust the rod end and test again.



Hope that helps.
JP

[Jim]

Thank you for the reply. My jack screw travel is 4 inches. I have the rod end screwed in as far as it will go. When I run the screw up it hits the cross tube. I disconnect the rod end and scissors link and screw the jack screw in, clockwise looking from the top, until it bottoms. The scissors tab is all the way down to the outer tube. When I run the screw up it goes the full 4 inches. Jim

[jtpitkin06]

Turning the actuator inner (black) tube in or out does the same thing as running the actuator with the motor. It simply rotates around the internal jack screw. The only adjustment in total length you have is the rod-end that screws into the very top.

Extended total length of the assembly from bolt hole in the bottom to the bolt hole in the rod end is approximately:

19-1/2 extended (with rod end fully in)
15-1/2 retracted (with rod end fully in)


The actuator moves a total of 4 inches. The stab will move about 4-1/2 when measured at the front of the slide blocks.

If the actuator’s extended dimension is greater than 20 inches it may cause the stab to strike the fuselage directly above the slide blocks.

If your actuator is greater than 20 inches, you have the wrong assembly for your aircraft.


JP