flap pump lever failure

[Comatose]

taking off this morning i noticed my flap lever was in the down position, with no restistance, and wouldnt stay up. my flaps will pump down, but then they retract after about 5 seconds. i made my flight uneventfully no flaps. i suspect that there is a leak somewhere. anybody run into this before, what was the cause and how long/much was the fix? i can live without flaps for a bit, what i am really concerned about is if i lost brakes as a result of the leak.  my home airport has no maintenance on field, wondering if i should fly direct to an msc, or if i should fly home and set up repair at my leisure. 

[Lionudakis]

It sounds like a control cable came loose or disconnected. Either behind the panel or under the belly. Sounds like the valve is not completely closed is why they are bleeding back up. The ends are a simple set screw on the control cable. Doesn't sound to bad. Since the lever sounds as if it is falling back down with next to no resistance, I'd bet its behind the panel/lever, just the resistance from the cable would hold the lever in position. The ends are a simple wire through a hole type connection, and a slotted set screw on top. 

[1964-M20E]

If I'm not mistaken the brakes come off below the flaps.   However, you say the flaps will pump down but not stay so that tells me you have plenty enough fluid and most likely do not have a leak.  Check under the plane for any sings of red hydraulic fluid.  I suspect that it is an issue with the cable that connects to the pressure release valve.  This is what allows the flaps to retract.  If it is not closed the flaps will pump down but immediacy retract.  If this is the case you could wait until you get home to get this fixed IMHO.  This will give you some practice on no flap landings.  I still do not know why Mooney changed from the mechanical linkage used on the B models.

[aminora]

We are having the same problem with our m20e. Our flaps (hydraulic) will not stay down but they will pump down then bleed back up. We hear there is an electric flap retrofit to eliminate the hydraulic flaps altogether. Anyone hear of those or done the retrofit? We would like to hear from you.

[N601RX]

The brakes come off the bottom of the tank, the flaps come off the side about an inch higher up.

[tony]

The brakes come off the bottom of the tank, the flaps come off the side about an inch higher up.

 

well then, perhaps he's just low on fluid.  Mike, if tha tis indeed the case, would he have to bleed the flaps like the brakes?

[N601RX]

well then, perhaps he's just low on fluid.  Mike, if tha tis indeed the case, would he have to bleed the flaps like the brakes?

There is a "T" fitting in the top of the flap cylinder. The rear end of the T has a cap on it. I removed the cap and pushed fluid in from there and it worked good. My flap lever has a fair amount of resistance. If it just falls down on its own I would assume the cable is broken or came loose from the back of the lever. The valve on the pump has almost no resistance.

[TTaylor]

On our C we had the same problem. My memory is it was the release valve that was bad. We replaced the valve and it worked fine. I think the new valve was the opposite of the old one. Pulled rather pushed.

[FloridaMan]

5 seconds? Mine like to hang out for around 30 seconds when on the ground. For that reason, I like to pump my take-off flaps out at run-up and then check them as I pull onto the runway to take off. When I retract them with the wing loaded in flight, they'll come right up. 

[N201MKTurbo]

There is an adjustment on the valve for how fast the flaps retract. If your flaps are coming up to slow, it can be fixed easily. If the flaps retract on their own, you can re-coin the seat where the ball bearing sits in the valve and that will stop the leak.

[carusoam]

Check how old the oil lines are, they leak after 45 years... If you have oil in the lower belly panels, you'll know why. Best regards, -a-

[N601RX]

I rehosed all my lines a few months ago. The ones behind the panel and under the belly still had the original tags from 67. They were not leaking, but were hard as a rock.

[carusoam]

Make sure air is out of the system? Clean the steal balls, change the O rings. Then readjust the valve for return rate when your done... Changing to electric sounds a lot more expensive and does the same job as the manual system... Best regards, -a-