PC not disengaging

[65C_flier]

Has anyone experienced a PC that won't disengage? My 1965 M20C has the basic wing leveler, but it has the electric solenoid (and yoke button) to disengage the PC. The wing leveler works great, but pushing the yoke button doesn't disengage. Not a major problem, but a bit annoying.

The yoke button has been checked and works perfectly. My A&P has also checked the solenoid and reported that it works (the yoke switch causes it to open/close). I'm out of ideas as to what could be causing it to stay on?

[Pictreed]

Mine acted the same way so I pulled the button out of the yoke.

[timj0rdan86]

i have a 67 F model and i am having a similar problem and was just reading in maintenance manual that you should test the Pilot Valve Operation ( cut-off valve) and replace if it is not shutting off completely. i have a suspicion this is the problem with mine, the main push/pull switch for the wing leveler does not disengage it nor does the shut off valve on the control yoke.

do you have any idea the cost of a new pilot valve or the maintenance required to replace it

[Shadrach]

Same year, same model, same problem... started trouble shooting on Monday.  My yoke switch checked out fine, so I think its the pilot valve in my case.

 

[carusoam]

Welcome aboard, Tim and MB...

Thought I was seeing the same thing in another thread.  Turns out Ross/Shadrach had posted that challenge in a thread yesterday...

See if that helps?

Best regards,

-a-

[Shadrach]

On 7/11/2018 at 6:00 PM, mbiggs said:

Has anyone experienced a PC that won't disengage? My 1965 M20C has the basic wing leveler, but it has the electric solenoid (and yoke button) to disengage the PC. The wing leveler works great, but pushing the yoke button doesn't disengage. Not a major problem, but a bit annoying.

The yoke button has been checked and works perfectly. My A&P has also checked the solenoid and reported that it works (the yoke switch causes it to open/close). I'm out of ideas as to what could be causing it to stay on?

If yours has a solenoid it differs from mine. 

[65C_flier]

Thanks carusoam and Shadrach. It sounds like the pivot / pilot valve or filters might be the culprit.

[FloridaMan]

Mine seems slow to disengage. I thought it was normal because of all the vacuum in the lines and servos. 

[takair]

Kinked disconnect button line can do the same.  Trace the line through the yoke and to the valve.

[timj0rdan86]

had my a&p check out my system the yoke button works so pilot valve is good he suggests cleaning the solenoid that should fix the problem