kap 150 alt hold problem

[flysamo]

m20 ovation with kap 150 auto pilot with intermitten altitude hold problem , set 9500 for example air will climb to 10000 and some times corrects, have to over ride to correct then systems works. trim control motor /clutch was just overhauled. Any ideals and repair shops in southern California that know these units, where does altitude control get signals from/ to auto pilot system

[carusoam]

Great question!

While waiting for an answer...

How many attitude servos are there... two?

• Your KAP150 holds altitude well, now that the trim servo is cleaned up.
• If there is another attitude servo... Does the other servo now need attention?

Check the BK site for the KAP guide. I think you have four servos with that...

Sounds like auto trim/alt hold may be a different function than level off at 10k’....

Sometimes the clutch slips, sometimes it doesn’t...

Might be worth a pre-emptive call to AP Central to get their opinion rolling...

PP thoughts only, not a mechanic...

Best regards,

-a-

 

[PTK]

7 hours ago, flysamo said:

m20 ovation with kap 150 auto pilot with intermitten altitude hold problem , set 9500 for example air will climb to 10000 and some times corrects, have to over ride to correct then systems works. trim control motor /clutch was just overhauled. Any ideals and repair shops in southern California that know these units, where does altitude control get signals from/ to auto pilot system

Flysamo, have you looked at the pitch servo? Alt capture and hold is primarily a pitch servo function. The pitch servo is located aft of the pitch trim servo. I'd urge you to give a call and speak with Alan or Steve at Autopilots Central. (918) 836-6418.

[Bolter]

Sometimes these systems need to be evaluated in the plane, so local (or Mooney-local) is helpful.  I have the KAP 150, and @kortopates recommended a shop in Sacramento (KSAC).  I think it was these guys:

http://www.executiveautopilots.com/

[skykrawler]

Read the pilots manual for the KAP-150.   Some testing of the servo is possible on the ground - without the engine running.  First, engage the autopilot - it should be in 'pitch mode' or vertical rate and there should be several pounds of resistance on the controls longitudinally that you can eventually override.   Use the vertical speed rocker switch and command climb - the column should move aft.  Command descent - is should move forward.   There is a torque sensor in the servo that the AP reads.  When the torque is above a threshold the AP drives the stabilizer.   While performing the above and overriding the servo with your hand the AP should drive the trim.   If this does not happen the torque sensor could have a problem.