28V Cowl Flap motor problem on M20J

[Philip France 13]

Hello,

I have a problem with the electric motor on the cowl flap of the engine,

There seem to be a short circuit in the winding of the motor : the breaker is popping out when I activate the switch to open or close the flap,

I have seen on Mooney catalog part found 880050-501 or 505 ? My plane is M20J MSE of 1994 Serial 24-3290,

Can you tell me the best option repair or replace & where to go for it ?

Thanks,

Philip

[kortopates]

We've written about this many times on Mooneyspace, here is a thread that covers it and note they have a new configuration of the motor a -513. See this thread, but basically Bobbi at Globe Motors (the OEM for these) will rebuild your existing one as a FAA Repair facility but basically they'll send you a new one using the latest -513 spec which requires larger roll pins - see the thread and google "Mooneyspace.com 880050-501 Globe" for more threads on this. The same cowl flap motors is used on the modern K's too.

 

[rgpilot]

When your changing the oil filter, always cover the motor. Most failures are from oil contamination.

[Gagarin]

What is the advantage of electric cowl flaps vs manual cowl flap?

[Mooney in Oz]

2 hours ago, Gagarin said:

What is the advantage of electric cowl flaps vs manual cowl flap?

Manual: Its either closed, half open or full open.

Electric: Any position you want.

I had my manual system reengineered, which included a vernier control knob whereby I can have any position I want.

[Philip France 13]

Hello

Thanks for your help i have contacted Bobbie ELDRIGE at Globe Motor AL and got my motor repaired for much better price compared to the Monney quote 3x less cot and fantastic support. Philip

[PT20J]

On 2/2/2020 at 11:42 AM, Gagarin said:

What is the advantage of electric cowl flaps vs manual cowl flap?

Good question. Frankly, I can't see any except increased maintenance costs. My 1978 J was manual and worked fine. My 1994 is electric and it works fine, too. When I first got it, I played around with different settings, but I didn't find any utility in it. Bob Kromer has stated that they fly a bit faster when cracked open, but mine doesn't. At some point Mooney changed the left cowl flap from flat to a bulged shape similar to the exhaust pipe bulge in the right flap. I'm not sure if this coincided with adding the electric motor or not. Maybe if you have electric cowl flaps and the flat left flap cracking makes a difference.

Does anyone find the electric cowl flaps very useful and if so in what conditions and on what model?

Skip

[kortopates]

8 hours ago, PT20J said:

Good question. Frankly, I can't see any except increased maintenance costs. My 1978 J was manual and worked fine. My 1994 is electric and it works fine, too. When I first got it, I played around with different settings, but I didn't find any utility in it. Bob Kromer has stated that they fly a bit faster when cracked open, but mine doesn't. At some point Mooney changed the left cowl flap from flat to a bulged shape similar to the exhaust pipe bulge in the right flap. I'm not sure if this coincided with adding the electric motor or not. Maybe if you have electric cowl flaps and the flat left flap cracking makes a difference.

Does anyone find the electric cowl flaps very useful and if so in what conditions and on what model?

Skip

They're extremely valuable in the Turbo K , providing infinite adjustment on how much airflow without the full open penalty drag of the manual system. But they are also re-engineered the cowl flaps from a pair of oval shaped flaps to one much larger center flap which my guess is provides more cooling with smaller openings. So I wonder how much benefit you may be getting just from the newer design even though you may have little need to adjust them. Regardless though, the updated flaps provide very little speed penalty upto about the 1/3 open. But up in the flight levels conditions can need even more than that. So personally on an aircraft flown from down low to well into the flight levels they're a huge improvement over the manual system.

[PT20J]

42 minutes ago, kortopates said:

They're extremely valuable in the Turbo K , providing infinite adjustment on how much airflow without the full open penalty drag of the manual system. But they are also re-engineered the cowl flaps from a pair of oval shaped flaps to one much larger center flap which my guess is provides more cooling with smaller openings. So I wonder how much benefit you may be getting just from the newer design even though you may have little need to adjust them. Regardless though, the updated flaps provide very little speed penalty upto about the 1/3 open. But up in the flight levels conditions can need even more than that. So personally on an aircraft flown from down low to well into the flight levels they're a huge improvement over the manual system.

For a K maybe. But for a J, I think they only increase my long-term maintenance costs. . 

[kortopates]

For a K maybe. But for a J, I think they only increase my long-term maintenance costs. . 

Your comments raised my curiosity as to why. Are you able to operate with them closed on cruise with that design?
I don't doubt that may be over designed in functionality on a J, afterall the big IO-550s in the R/S don't even have cowl flaps. Just the turbos.


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[KSMooniac]

Mine stay closed in cruise on my 77 J, running LOP of course. If it is really hot, though, I'll go a little further LOP to keep CHT at 380 or below.

I would like to update to the newer flaps someday, though.

Sent from my LG-US996 using Tapatalk

[PT20J]

Both by J’s — one manual and one electric— would cruise @ 70% with the cowl flaps closed at peak EGT with hottest cylinder 380 F or less. Manual one had flat left cowl flap rigged slightly open when closed to make room for the tubes, and electric one has the bulge. 

[gsxrpilot]

Echoing what @kortopates said, the single large cowl flap on the 252's in really nice to have. Up in the flight levels without enough oxygen molecules to pull the heat off the cylinders, I can tap the button on the cowl flaps to open them to exactly what's needed for proper engine temps.

And after getting Bobbie to rebuild the cowl flap motor, it's been running beautifully ever since. I expect that's a one time event as well.

BTW... mine stay closed once in the descent and all the way to the hangar or parking. With the cowl flap open, the turn limits marks on the nose gear are obscured. So keep the cowl closed up and the turn limit marks visible. 

[kortopates]

11 hours ago, PT20J said:

Both by J’s — one manual and one electric— would cruise @ 70% with the cowl flaps closed at peak EGT with hottest cylinder 380 F or less. Manual one had flat left cowl flap rigged slightly open when closed to make room for the tubes, and electric one has the bulge. 

That makes sense then why you don't need electric cowl flaps.

23 hours ago, KSMooniac said:

Mine stay closed in cruise on my 77 J, running LOP of course. If it is really hot, though, I'll go a little further LOP to keep CHT at 380 or below.

I would like to update to the newer flaps someday, though.

Sent from my LG-US996 using Tapatalk
 

I do suspect the new design that Skip has will give you more cooling with less drag - but I have no direct data.

But the NA birds are a world apart from the turbo's when it comes to cooling requirements and thus cowl flap requirements. The NA engines are generating less power as altitude increases and therefore less heat above some point (8-12K, depending on how operated) while turbo's are generating the same power all the way up to the flight levels but with the thinning atmosphere our cooling air demands are increasing with altitude as @gsxrpilot commented above. 

[Marc Taylor]

What is the correct set up for the single flap?  My service manual only refers to the 2 flaps the earlier K's had.

Looks like I need to replace the motor and would like to have it set up correctly.

 

[carusoam]

Let’s invite Paul @kortopates back to the conversation...  (question about cowl flap motor...)

Best regards,

-a-

[Will.iam]

There are 3 marks on the electric cowl flap indicator and the POH spells out the speed penalty at each mark. I think it was 2kias loss 4 kias and 6 kias loss. It was very accurate to the value what ever they are. 

[kortopates]

On 2/8/2021 at 11:10 AM, Marc Taylor said:

What is the correct set up for the single flap?  My service manual only refers to the 2 flaps the earlier K's had.

Looks like I need to replace the motor and would like to have it set up correctly.

 

see 71-13-02 for the flap rigging and 71-13-03 upto sn 3410 or -04 for sn 3411 on for rigging the indicator 

It basically begin by adjusting them to close flush with the contour of the cowling. 

But you won't have to re-rig them if you merely remove and re-install the motor. Just remove the motor removing the roll pins on the shaft and the 4 atteching screws that mount the motor to its holding bracket. Depending on which motor you originally had, your overhauled motor coming back from Globe may have a larger diameter holes for  the roll pins and if so you'll have to drill out the attaching part to fits the larger roll pins to secure it to the shaft. (from memory) 

[MarcJohnson]

On 3/6/2020 at 6:05 AM, Philip France 13 said:

Hello

Thanks for your help i have contacted Bobbie ELDRIGE at Globe Motor AL and got my motor repaired for much better price compared to the Monney quote 3x less cot and fantastic support. Philip

Bobbie at Bobbie Eldrige (Rockstar) at Globe Motor AL and got my motor repaired.  Turned around in two weeks.  Less than a third of the cost of new from Mooney.  Mooney, please, I want you to succeed, but....  Mine is installed and out of the way in cruise.  SWEET!!!