FX3 Interior panel removal - propeller cable failure

[Tsquared]

For those FX3 owners who have not had to remove the interior, left side panels for maintenance, I documented the the removal of my panels when I removed them to allow replacement of a failed propeller control cable (part number SP58011-007, $239 + shipping) I’ve been told a number of FX3’s have required replacement prop control cables early. Mine needed it at 413 hrs.

Removing the left side panels is pretty easy, but can be a bit frustrating. It took me a leisurely 2.5 hrs to complete. I used the CK-KM308 EX3 Finish Manual Rev B as a start point. The manual documents the process EX3 builders use to assemble the interior of the plane.

Before starting I strongly recommend getting some plastic auto trim removal tools that are no scratch. Don’t use anything metal…. Don’t ask me how I know. Also get some extra plastic rivets and either a lot of small bags or some sort of organizer so you can keep the screws and parts organized.


Before starting I pulled the ignition and starter CB’s and moved my fuel selector to off just be to on the safe side.

1 - remove the throttle and prop control knobs from both the pilot and passenger levers. Also remove the metal guides as well. Your going to need to remove the knobs first, then turn the metal guard 90 degrees to remove it.

2 - remove the plastic rivets from the forward panel.

Note the top of the panel has a cut out for some wires. You will have to work the panel around the cables to get the panel out.

3 - pull the front panel back to slide it out.

4 - The fuel selector switch needs to be taken apart before the middle panel can be removed. Having the diagram from the finish manual handy helps with the disassembly and assembly of this component. Unscrew and remove the selector switch. Note this took more effort then I expected it to. Its press fit as well as screwed in

5 - Remove the press gate. WARNING - there are springs behind each of the screws. Go slow and don’t lose these.

6 - remove the screws holding the carbon fuel select panel. Note there are small plastic washers behind each screw.

7 - remove the “washer/cover” that covers the hole the throttle lock knob stick thru. Note the cover has adhesive on it, so store it appropriately so it can be reused. I’m told that little “washer/cover” costs $40

8 - remove the pully covers attached to the floor. They are not attached to the panel, but removing them will help removing the panel.

9 - remove the hose from the heating

10 - use a car panel remover to loosen the velcro holding the middle interior panel from the exterior panel and slip the control levers outside the panel.

11 - remove the remaining plastic rivets from the middle panel.

12 - Once the panel is free, this is where the fun begins. I found it easiest to shift the panel forward to allow the rear of the panel around the rudder cables guide and doing this while lifting the middle of the panel up to move the panel around the aileron cable on the floor. work the front of the panel loose first then

13 - once clear of the rear panel, its fairly easy to pull the rear of the panel up and back (freeing the hot air Chanel from the frame under the panel) and remove the whole thing.

Reinstalling the panels is just the reverse. I was able to reuse some of the plastic rivets I originally removed, but needed a handful of new rivets.

Hope this helps. Doing it myself likely saved 5 hrs of AP labor ($500+).

 

[Neal]

Great write-up, thanks for sharing. Can you share details on the prop cable failure, symptoms, what you learned about it, anything after removing it - observations?

As this seems to be common I'm being more gently with mine. I hear it's stranded cable, can kink, etc.

 

[lrobichaux]

Great write-up, thanks for sharing. Can you share details on the prop cable failure, symptoms, what you learned about it, anything after removing it - observations?

As this seems to be common I'm being more gently with mine. I hear it's stranded cable, can kink, etc.

I've got the same question. What were the symptoms of the failure?

 

[Cubonaut875]

Awesome post and documentation. I have to take my anel off sometime as I think the check valve for my smoke system is not directly behind the firewall as it should be. I'll check the cable out at that point also.

 

[Tsquared]

Prior to an evening flight, I cycled the prop during my run up. Cycling the prop resulted in a very stiff prop lever movement accompanited by a ratchet or grinding sensation in the lever. The amount of effort/force needed to move the prop lever was considerably more than normal. I aborted the flight and went back to the hangar.

After pulling the top cowl off that weekend to inspect things I was able to capture the videos below with the noise. Turn up the volume and you will hear the noise. the new cable is silent.

 

[Cactus Charlie]

I have replaced my FX-3 prop cable twice! The first at 159 airframe hours and the second at 345 airframe hours (185 hours in service). I have 98 hours on the third one and it's ok so far.

The symptoms were increased resistance to movement, binding that felt like a broken strand of the inner catching on the outer, limited range of motion, then binding up solid for the second cable. The throttle cable which has more bends than the prop cable has shown no problems.

The cable is a Cablecraft Products part number 184VTT3-57 which decodes as follows -

 

[Neal]

Did you replace it yourself? How involved is it should someone have to do it? Any idea what's causing the failures? Is there a better alternative? @Tsquared I think you said your A&P may have a better option?

 

[Cactus Charlie]

Yes, I changed the prop cables myself.

I suspect the second cable failed because it was coiled very tightly for shipping. The third was shipped in a straight tube.

 

[Tsquared]

Did you ever look at getting one made by McFarlane? My A&P highly recommended them. I’m planning on having them make a spare for me.

 

[Cactus Charlie]

To add to Tsquared tips -

• I used a small plastic kitchen scraper to separate the velcro.
• I used cardboard strips to keep the velcro separated
• I disconnected the left rudder cable at the rudder to make it easier to get the center panel past the cable
• I used headless studs to keep the fuel valve in position while the cover panel was located. I removed one stud and replaced with final screw then removed second stud and replaced with final screw
• I closed the gap between floor pan and fuselage with towels to stop anything dropping in the gap
• I use a cardboard sheet to protect the fabric while working on the throttle/prop quadrant.

I removed the front seat for the first cable replacement but left it in place for the second one.

 

[Cactus Charlie]

Did you ever look at getting one made by McFarlane? My A&P highly recommended them. I’m planning on having them make a spare for me.

No, I had not considered that.

If you ask for a quote would you please ask about minimum quantity for discount pricing. Maybe other FX/EX owners would like to have a spare or do the initial build with a better cable.

What is their source for the raw cable components? Cablecraft parts are made in China but, if I understand correctly, the cables provided by CubCrafters are fabricated in US. Is McFarlane one of the assemblers of Cablecraft parts?