M20J sporadic gear retraction failure

[ndirishpilot]

Hi Mooney people,

My instructor has an early 80's M20J (I think it's an '82) and is having problems with the gear failing to retract, usually when it's cold.  Yesterday we took off to put gas in it at another airport.  The gear came up just fine on the way over but wouldn't retract on the way back...we had to just fly it with the gear down.  This has happened off and on since he got the plane about two years ago.  He's had it in the shop a couple of times but they have never been able to recreate the problem...it always retracts just fine.  And he hasn't had issues with it in the summer.

 

What happens is the gear handle comes up, and it sounds like the system doesn't do anything.  I listened for the motor but couldn't hear it (not sure if I could if it was working).  No warning lights come on; the "gear down" annuciator stays lit as does the light on the floor.  Cycling the gear handle has no effect.  Some folks at AOPA suggested the rubber donuts aren't expanding in the cold and hitting the squat switch, but I feel like, if that was the case, we would get a "gear warn unsafe" light as if we were trying to retract it on the ground.

Any ideas?

[Piloto]

Check that the emergency gear lever is properly latched. This is the most comon cause. If properly latched its cable may need re-rigging (increase tension).

José

 

[rbridges]

sure beats the heck out of the opposite problem of gear not lowering.

[Hank]

I have sporadic winter problems with the gear, too. The right one will stay down about an inch [as reported by friends in other planes] when cold, but will eventually raise the rest of the way. Until the recent sighting, I thought it was just the microswitch in the belly. The motor hums, the gear move, but the gear up light won't come on, the floor indicator shows transit, and the durn squeal in the headset won't stop . . .

[MooneyMitch]

I had this issue sometime back on my F model [electric gear].   This is just a suggestion for your mechanic.  Place the aircraft on jacks and remove the belly panels close to the micro switches and gear motor.

Attempt to recreate the problem.  If it does occur, tap around on the micro switches, motor and all connections in order to get the gear to retract.  This may lead you to the answer.  As always, please let us know the outcome.

Happy Mooney flying!

 

[thinwing]

I wonder about "the squat switch"...I donot think Mooneys use one..Its an air pressure activated safety interlock.The a/c has to be moving faster than about 40mph before it allows the gear to retract...if switch is faulty or intermittent it will cause non retraction...this is true for later models...I donot know if a 80s model uses this system...if it does there should be a red bypass button next to gear switch...k

[Hank]

Quote: Mitch

I had this issue sometime back on my F model [electric gear].   This is just a suggestion for your mechanic.  Place the aircraft on jacks and remove the belly panels close to the micro switches and gear motor.

Attempt to recreate the problem.  If it does occur, tap around on the micro switches, motor and all connections in order to get the gear to retract.  This may lead you to the answer.  As always, please let us know the outcome.

Happy Mooney flying!

 

[jelswick]

Mine did the same thing ndirishpilot.  Took off for fuel, no gear retraction, cycling made no difference and landed and turned it over to the shop.  That was on my '81, so the timing of yours wearing out, if it's the same issue, might be about right.  My mechanic isolated it to the gear motor which ended up sent out to and rebuilt by Lasar.  I can't describe the exact issue that drove it, but it involved worn rods in it that they replaced.  Tail # is N1145T and I would assume Lasar could let you know more detail of what the issue turned out to be.  I was glad to just pay for the rework of the box and new parts in there knowing I should hopefully get another many years without it being an issue again.  Sorry I can't offer more technically on it, but it sounds like a very similar issue to what you encountered and depending how many of these Lasar does, I'm assuming they should be able to help with details.  My mechanic has always been very pleased working with them when the Mooney has any issues he's needed assistance with. 

[ndirishpilot]

Quote: jelswick

Mine did the same thing ndirishpilot.  Took off for fuel, no gear retraction, cycling made no difference and landed and turned it over to the shop.  That was on my '81, so the timing of yours wearing out, if it's the same issue, might be about right.  My mechanic isolated it to the gear motor which ended up sent out to and rebuilt by Lasar.  I can't describe the exact issue that drove it, but it involved worn rods in it that they replaced.  Tail # is N1145T and I would assume Lasar could let you know more detail of what the issue turned out to be.  I was glad to just pay for the rework of the box and new parts in there knowing I should hopefully get another many years without it being an issue again.  Sorry I can't offer more technically on it, but it sounds like a very similar issue to what you encountered and depending how many of these Lasar does, I'm assuming they should be able to help with details.  My mechanic has always been very pleased working with them when the Mooney has any issues he's needed assistance with.