Fixed flap issue

[Joshua Blackh4t]

Just thought I'd share this, maybe someone will benefit from it.

My E has hydraulic flaps that have always been lazy coming up.

I have had it for 2 years and over 200 hours but no other experience with hydraulic flap mooneys so I thought it was normal.

Quite often I'd have to hold it up as hard as I could to get them to retract, seemed better on take-off than ground, but still not perfect.

It seemed to be worse in winter than summer so I thought it could be the fluid, maybe a valve not working properly, but as long as it kept doing its job it was ok.

Recently it was getting worse, very annoying and would need moving a couple of times to get them to retract.

Today they finally got too annoying, I was at the same airport where my mechanic is, so I taxiied over to him, and had a look at it with him there in case it got beyond my level.

Pulled off the inspection cover, pushed the lever to release and came up sweet as butter.

So I thought it just needed adjustment. Then I looked closer and the cable wasn't moving as far as it should so I soaked it in spray lube and...... it started working better than I have ever know them.

So now I know. If they need more than light pressure, or need holding the lever up, then lube the cable.

So simple.

No photos of the mechanism so I'll add a photo of my baby for fun. 

 

[Fly Boomer]

15 hours ago, Joshua Blackh4t said:

No photos of the mechanism so I'll add a photo of my baby for fun. 

I think these birds look kind of elegant, don't you?

[M20F-1968]

 

 

On 8/1/2023 at 3:59 AM, Joshua Blackh4t said:

Just thought I'd share this, maybe someone will benefit from it.

My E has hydraulic flaps that have always been lazy coming up.

I have had it for 2 years and over 200 hours but no other experience with hydraulic flap mooneys so I thought it was normal.

Quite often I'd have to hold it up as hard as I could to get them to retract, seemed better on take-off than ground, but still not perfect.

It seemed to be worse in winter than summer so I thought it could be the fluid, maybe a valve not working properly, but as long as it kept doing its job it was ok.

Recently it was getting worse, very annoying and would need moving a couple of times to get them to retract.

Today they finally got too annoying, I was at the same airport where my mechanic is, so I taxiied over to him, and had a look at it with him there in case it got beyond my level.

Pulled off the inspection cover, pushed the lever to release and came up sweet as butter.

So I thought it just needed adjustment. Then I looked closer and the cable wasn't moving as far as it should so I soaked it in spray lube and...... it started working better than I have ever know them.

So now I know. If they need more than light pressure, or need holding the lever up, then lube the cable.

So simple.

No photos of the mechanism so I'll add a photo of my baby for fun. 

 

There is a screw on the hydraulic flap pump which regulates the speed of the upcoming flaps.  They should come up in something like 12 seconds from full flaps to full up.  There is a specification in the maintenance manual.  The hard part is that the screw adjustment is very sensitive.  You will barely move the screw and change the speed by 2-3 seconds.  I forget which way to turn the screw to shorten or lengthen the time.  The screw to used to set the adjustment is at the end of the flap pump and has a locking nut to tighten it down.

John Breda

[N201MKTurbo]

You screw it in to go slower and out  to go faster.

[Skates97]

4 hours ago, M20F-1968 said:

 

 

There is a screw on the hydraulic flap pump which regulates the speed of the upcoming flaps.  They should come up in something like 12 seconds from full flaps to full up.  There is a specification in the maintenance manual.  The hard part is that the screw adjustment is very sensitive.  You will barely move the screw and change the speed by 2-3 seconds.  I forget which way to turn the screw to shorten or lengthen the time.  The screw to used to set the adjustment is at the end of the flap pump and has a locking nut to tighten it down.

John Breda

Very sensitive might be an understatement.  The difference between too fast and not moving at all is miniscule.

[N201MKTurbo]

17 minutes ago, Skates97 said:

Very sensitive might be an understatement.  The difference between too fast and not moving at all is miniscule.

Not one of Mooney's better designs. But it doesn't seem to change once adjusted, so it is not terrible.

[Shadrach]

Just be grateful that your mechanic is a 'first do no harm' kid of guy.  I can envision a number of scenarios where someone unfamiliar with the system might decide to be more invasive in their investigation. I have an inbox full of DMs on jobs started that were not properly finished.  

I won't name names but one owner had a mechanic clamp the cable for the up/down lever to the elevator push rod tube next to the pump.  Flaps worked fine on the ground but pitch changes would raise the flaps in the air....

[DCarlton]

7 hours ago, M20F-1968 said:

 

 

There is a screw on the hydraulic flap pump which regulates the speed of the upcoming flaps.  They should come up in something like 12 seconds from full flaps to full up.  There is a specification in the maintenance manual.  The hard part is that the screw adjustment is very sensitive.  You will barely move the screw and change the speed by 2-3 seconds.  I forget which way to turn the screw to shorten or lengthen the time.  The screw to used to set the adjustment is at the end of the flap pump and has a locking nut to tighten it down.

John Breda

12 sec!?  Mine has always been a lot quicker than that.  Based on some of the comments, I'm inclined to leave my alone though.  

[Shadrach]

28 minutes ago, DCarlton said:

12 sec!?  Mine has always been a lot quicker than that.  Based on some of the comments, I'm inclined to leave my alone though.  

That’s ground retract speed. They retract faster under aerodynamic load.

[N201MKTurbo]

I have found it works best to have someone pull up on the flaps and set them to come up in 5 seconds with someone pulling up on them. You may ask? How hard are they pulling up on them? You know, not too much, but just enough...

[Immelman]

OP is describing an issue with the retraction lever/cable..... far different from the retraction speed adjustment on the pump.

Where that cable attaches to the flap pump is not the most robust clamp. Basically #8 (+/-) philips head machine screw that clamps (pinches) the cable to a lever on the flap pump. The rigging for keeping the flaps down (or retracting them) is simply clamping the retract cable in the correct spot. I only point this out to suggest that if it gives you more trouble, to ensure that its clamped/fixed to the pump securely.

Edited August 26, 2023 by Immelman

[M20F-1968]

On 8/25/2023 at 3:07 PM, DCarlton said:

12 sec!?  Mine has always been a lot quicker than that.  Based on some of the comments, I'm inclined to leave my alone though.  

The speed is faster if you are in the air.  The manual gives the specs for testing on the ground.

John Breda