Resistor on cowl flap motor?

[cessnadriver]

Hello ALL.
I'm currently modifying my '65 C337's cowl flap selector levers to the newer model's electric switches. Here's my question. There is a resistor shown near the electric motor (in parallel) PN# Val 3-200. Does anyone know the value of this resistor? AND what it does in the circuit?
Thanks in advance.
BILLS

[edasmus]

Hi BILLS,

I do not have an answer to your question but I am going to offer a little thought here. I have occasionally thought over the years that having manually operated cowl flaps would have been my preferred choice over the electric version that I have on my 73 G model 337. I have not had much problem over the 11 years that I have owned the airplane but one of my electric motors needed to be replaced years ago and the other was disassembled and cleaned up by my IA. These motors do occasionally require service which translates to dollars. I have thought that manually operating the cowl flaps as designed in the early model SkyMasters would have been the better of the two systems from a simplicity stand point. This is simply my opinion. Think about it. Maybe others can offer some opinion here as well.

Good Luck

Ed

[hharney]

Bill
Are you going from the levers to the toggle switches on the panel? Or are you referring to the limit switches on the firewall?

[cessnadriver]

Herb.
I'm using 8 sets of micro switches instead of the two DPDT switches that are in the newer models. I mounted the micro switches to the original cowl flap levers and added three layers of plexiglass for the additional micro switches. My original question was about the resistor mounted near electric motor.But I discover, through further studies of the schematics that the resistor is only needed for cowl motors with three wires coming from it. Mine do not have the three wires.
Thanks, BILLS

[cessnadriver]

Edasmus.
My '65 C337 is the model you mentioned, BUT it's NOT manual. The cowl levers are connected to a push-pull cable AND to electric micro switches under the panel. From what I can figure, when you move the levers they charge the micro switches and the cable is the limiter??
Thanks, BILLS

[edasmus]

OK Bills....Thanks for the info and good luck with the project.

Ed

[GMPoland]

I ran into several problems with my rear cowl flap motor with this resistor being installed on the wrong wire. I have a Cessna wire diagram that shows installation if you still need info. GMPoland@graceba.net.

[cessnadriver]

GM Poland
The diagram you have, is it the diagram from the back of the Service manual? If so, I have that one.
Thanks, BILLS

[JimC]

I haven't seen a schematic, but it's possible the resistor is there to prevent the flaps from driving the motor and closing under pressure.

[GMPoland]

No. Service and parts manual were vague. I got some help from a Service Rep by the name of Bill Glen. I will post it anyway so you can check and see if it clears up questions. MIne had resitor wired incorectly resulting in motor burning out when imprperly rigged by same mechanic. Will Post tonight on work computer now.
I cant get the file to upload due to size. (1.55Mb) please e-mail me or PM on this site and I will email you the two diagrams. GMPoland

[Skymaster337B]

I just checked the resistor, with a multi-meter, on my 337B. The resistor had exactly 3 ohms. The parts manual lists it as a VAL3-200.