Skymaster Forum

Skymaster Forum (http://www.337skymaster.com/messages/index.php)
-   Messages (http://www.337skymaster.com/messages/forumdisplay.php?f=1)
-   -   Rear cowl cable replacement (http://www.337skymaster.com/messages/showthread.php?t=5081)

MelsML55 11-11-21 07:40 PM

Rear cowl cable replacement
 
Anyone have experience replacing the cable for the rear cowl flap assay that runs all the way to the cowl flap controls? Mine is frozen solid.
Keith 817-991-4318

wslade2 11-12-21 12:04 AM

Do you not have electric cowl flaps? I remember reading about a mod that changes them to manually operated. I’ve not had experience with that, but flap elevator trim interconnect cable is a pretty long push pull and mine was frozen solid. Aircraft spruce sells that type cable by the foot. apparently you can soak in oil and hope to free up. But I just swapped it out with new.

https://www.aircraftspruce.com/catal...clickkey=66687

TomM 11-12-21 01:45 PM

Mel is more than likely referring to the mechanical cable that goes from the flaps back to the switch system. At least on the older ones like mine, there is a push/pull cable that goes from the flap cross arm back to the levers that control the flap position through a number of micro switches behind the flap controls. There is one on the front as well, just much shorter obviously.

I dont know if you are going to find one of those.....McFarlane will make any type of cable system you need, but it might not be FAA-PMA. You may have no other choice. Maybe this fits in the "owner fabricated" part or AC23-27 regarding part and materials substitution for vintage aircraft.........

Forgot to add that the replacement activity is actually pretty straight forward. You will need to remove the floor but the cable runs from the firewall, under the floor then up to the flap control levers. If you remove it and send to McFalane, they can easily make a new one as it has standard end fittings.

If you remove it you may also be able to work it loose by spraying penetrating oil through both ends, but not sure if you want to trust that fix. A frozen or sticky cable puts a lot more stress on that crappy little flap motor which costs a ton to replace.....

MelsML55 11-30-21 03:18 PM

With the help of Matt Elder I have a new plan to upgrade to the later model style that uses micro switches. Thank you for your input!

TomM 12-01-21 12:03 AM

Matt is a good guy. He helped me out with rebuilding my flap motor.

kbecker 12-01-21 04:09 AM

My experience with the microswitches is that they can sometimes get out of adjustment and if that happens, even slightly, the cowl flap motors will continue to run and burn out. As we all know they are expensive to replace.

My 77 337G has this set up, but I never depend on the microswitches to turn off the cowl flap motors. As soon as I get the indicator lights that the cowl flaps are open or closed, I return the selector switch to the middle (off) position. Using this method I haven't (knock on wood) had a cowl flap motor issue in 20 years.

Just my 2 cents.

Kevin

n86121 12-05-21 02:41 PM

Add a fuse to protect motors!
 
The cowl flap arrangement was poorly thought out. It exercises the wiring bundle and mechanism with each cycle.

Probably someone at Cessna said, 'We forgot the cowl flap motor, so make it fit in this rectangular foot print."

I can't recall, but I believe a 2a inline fuse could save you a lot of grief.

D


All times are GMT -4. The time now is 03:16 AM.

Powered by vBulletin® Version 3.6.9
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.