252 Encore Cowl Flap Operation

[Encore Driver]

Is the cowl flap system on the 1997 Encore supposed to be adjustable throughout it's entire range? Mine will hold in the closed position and hold in the open position but if it is set any other place it slowly bleeds to the about half open. Every 10 minutes or so it needs reset to maintain oil temp. Is this normal for this system? If not, I'll have the motor rebuilt. It currenly has a Globe Motor 880050-505 cowl flap motor and in speaking to Globe they now have an 880050-513 motor. Are they interchangeable?

Steve

 

[Parker_Woodruff]

Yes, you should be able to keep it stationary across the entire operating range.

[David Mazer]

The 252 cowl flaps are supposed to be infinitely adjustable and it requires the motor to do all the work.  The motor itself is very small and fails frequently.  On a Rocket the motor is prone to getting oil drips which also causes it to fail.  I converted mine to a manual system after being unable to get a motor.  I can tell you the forces are significant and required a manual locking system to hold the flaps closed despite using a very heavy push rod.  My guess would be your motor is failing.

[fantom]

It is a simple, small motor. Very easy to take apart and clean up. I had to do it once in twenty years.

 

Not to start an old debate, I use my flaps on all take-offs and almost all landings.

[LANCECASPER]

Is the cowl flap system on the 1997 Encore supposed to be adjustable throughout it's entire range? Mine will hold in the closed position and hold in the open position but if it is set any other place it slowly bleeds to the about half open. Every 10 minutes or so it needs reset to maintain oil temp. Is this normal for this system? If not, I'll have the motor rebuilt. It currenly has a Globe Motor 880050-505 cowl flap motor and in speaking to Globe they now have an 880050-513 motor. Are they interchangeable?

Steve

Having gone through this earlier this year, send it in to Globe and they will rebuild it. When it comes back I think it's the updated roll pins used that make it the -513. It comes back just like new for around $400.

[David Mazer]

It is a simple, small motor. Very easy to take apart and clean up. I had to do it once in twenty years.

 

Not to start an old debate, I use my flaps on all take-offs and almost all landings.

I presume we are talking about different flaps here.  I was talking about cowl flaps.

[fantom]

I presume we are talking about different flaps here. I was talking about cowl flaps.

Me too....cowl flap motor.

[PeytonM]

I had the exact same issue with my 89 J. Before you send it for repair, take a look at the plastic tie wrap(s) around the motor. Although the motor is attached to the airframe, there is at least one nylon tie wrap that goes around the motor. Confirm it is tight. If not, replace it. I fixed mine and that resolved the problem. Must have been the vibration.

[kortopates]

Is the cowl flap system on the 1997 Encore supposed to be adjustable throughout it's entire range? Mine will hold in the closed position and hold in the open position but if it is set any other place it slowly bleeds to the about half open. Every 10 minutes or so it needs reset to maintain oil temp. Is this normal for this system? If not, I'll have the motor rebuilt. It currenly has a Globe Motor 880050-505 cowl flap motor and in speaking to Globe they now have an 880050-513 motor. Are they interchangeable?

Steve

They are not interchangeable since the -513 has larger holes for the attaching drift pins than your older -505. That said, this is an improvement  and essentially an upgrade to the original -505 motor, yet it will require drilling out the attaching the 2 lever arm pin holes  to accommodate the larger drift pins (or roll pins) and installation of the larger pins. The exact affected part numbers are listed in my earlier post (that you commented on as well). See my earlier post and Lance's about whom to contact at Globe at http://mooneyspace.com/topic/8315-m20k-252-cowl-flap-motor/  

[kortopates]

I had the exact same issue with my 89 J. Before you send it for repair, take a look at the plastic tie wrap(s) around the motor. Although the motor is attached to the airframe, there is at least one nylon tie wrap that goes around the motor. Confirm it is tight. If not, replace it. I fixed mine and that resolved the problem. Must have been the vibration.

Your description is confusing only in that there are no ty-wraps used to secure the motor. Its secured by 4 screws & nuts to firmly attach it and tie wraps are used only to secure the wiring. Something must be amiss with your installation if a tie wrap is needed to secure the motor? I'd get it checked out by your A&P.

[PeytonM]

It's actually not securing the motor. Wiring around the motor. Sorry for the confusion.

[Encore Driver]

They are not interchangeable since the -513 has larger holes for the attaching drift pins than your older -505. That said, this is an improvement  and essentially an upgrade to the original -505 motor, yet it will require drilling out the attaching the 2 lever arm pin holes  to accommodate the larger drift pins (or roll pins) and installation of the larger pins. The exact affected part numbers are listed in my earlier post (that you commented on as well). See my earlier post and Lance's about whom to contact at Globe at http://mooneyspace.com/topic/8315-m20k-252-cowl-flap-motor/  

I followed your advice and sent the motor to Bobbie Eldridge at Globe Motors Inc. Waiting to hear what they found. The arm that was attached to the cowl flap motor evidently had roll pins that were too short and the motor shaft had spun inside the arm at some time in the past. This had been repaired with longer roll pins but it was not a tight connection. I'm not sure that larger diameter roll pins with the -513 motor will completely fix it. Seems like in your post you had priced the arm? If so was it from Mooney?

Thanks

Steve

[kortopates]

I followed your advice and sent the motor to Bobbie Eldridge at Globe Motors Inc. Waiting to hear what they found. The arm that was attached to the cowl flap motor evidently had roll pins that were too short and the motor shaft had spun inside the arm at some time in the past. This had been repaired with longer roll pins but it was not a tight connection. I'm not sure that larger diameter roll pins with the -513 motor will completely fix it. Seems like in your post you had priced the arm? If so was it from Mooney?

Thanks

Steve

Yes, the original same Lever Arm you have now is available from Mooney for the price I listed a year ago. But like you and most people in this predicament the roll pin holes had grown in size from being loose. So I ordered a new Lever Arm from Mooney before I realized my motor coming back from Globe would have bigger roll pin holes in the shaft. The larger roll pin holes was good news in that it enabled me to re-drill the my old lever arm holes to the new size and return it to "like new" condition saving the cost of the new Lever Arm. Its very unlikely that your current lever arm holes would be so enlarged that the same fix won't return your existing one to like new as well. But if I am wrong, keep in mind the new matching lever arm part is not listed in our IPC, nor had Mooney manufactured the first one as of a year ago. They just spec'd out the new motor (-513) at the time the Encore went out of production and have been using it for spares ever since so I assume the lack of demand for the new lever arm part has been pretty non-existent. So I really doubt you'll have any problem with yours either. You can get the drawing for the new spec'd lever arm from Mooney to tell you the proper size hole or just measure the new pin holes on the motor shaft when you get it back ( or I can find my copy of the drawing and email it to you). I had mine drilled by a friend in a machine shop so I wouldn't risk damage given the two holes have to be aligned up with the motor shaft, but access to a good drill press should be adequate too. 

Make sure both of the new roll pins are properly secured with safety wire to so that they never are allowed to work there way out.

Given your description, I am sure your pin shaft holes are enlarged and you will need a new shaft. So I am sure Bobby will have a new motor out to you within a week. They're great but they can't sell them outright, only overhaul them due their relationship with Mooney.