Ram Air Cable

[TWinter]

My ram air cable is frayed and needs replacing. I haven't put my A/P on it yet, but we noticed it had some fray on it near the front during the last annual a few months back. I'm having my new wig/wag LED landing light put in sometime during the next few weeks and thought I might have him tackle the ram air cable at the same time since the cowl will be pulled a part. Any suggestion on the best source for the new cable. I guess it should be noted is that my 73E has the ram air as the lever sliding up/down switch on the center console. I've seen a few push/pull cables on EBay and didn't know if they hooked up similar or were even acceptable to use.

Thanks,

-Tom   

[N201MKTurbo]

My hangar fairies once just replaced the wire on that cable. Cut the bent up end off so it will slide out easily and pull the whole thing out from the panel side. Get a new piece of piano wire from McMaster Carr. Put the old wire in a vice, tighten a crescent wrench on the wire and tap it with hammer to drive the knob shaft off of the wire. Drive a drill bit that is just larger then the wire into the crimp to open it up. Put the new wire in the shaft and re-crimp.

Don't lose the little ball.

Edited February 19, 2016 by N201MKTurbo

[Shadrach]

1 hour ago, TWinter said:

My ram air cable is frayed and needs replacing. I haven't put my A/P on it yet, but we noticed it had some fray on it near the front during the last annual a few months back. I'm having my new wig/wag LED landing light put in sometime during the next few weeks and thought I might have him tackle the ram air cable at the same time since the cowl will be pulled a part. Any suggestion on the best source for the new cable. I guess it should be noted is that my 73E has the ram air as the lever sliding up/down switch on the center console. I've seen a few push/pull cables on EBay and didn't know if they hooked up similar or were even acceptable to use.

Thanks,

-Tom   

On my 67F the Ram Air cable is solid with a coil wrap; there is no chance of it fraying.  In fact, I doubt a woven cable would be rigid enough to hold the door closed in flight.  Can you post a pic of the "fraying" cable?

[TWinter]

22 minutes ago, Shadrach said:

On my 67F the Ram Air cable is solid with a coil wrap; there is no chance of it fraying.  In fact, I doubt a woven cable would be rigid enough to hold the door closed in flight.  Can you post a pic of the "fraying" cable?

I'll try to get to the hanger this weekend and get a pic. I mentioned to my AP that the Power Boost was difficult to move. He checked it out at the last annual. He pointed to the cable and said that it was nearly worn through and not operating smoothly..Said that he could try to replace it then or we could wait until the next shop visit and go from there. While he had open I just took a quick look into the cowl area and saw the frayed area he was pointing out. Don't remember exactly what it looked like. Not knowing what the annual bill was going to be I passed on the repair then knowing I would be back after New Year for the light install. Drives me nuts knowing something is not 100%. Just thought I would try to source the cable and be ahead of the game.

I'll try and see if I can get a pic over the weekend.   

 

-Tom

[Shadrach]

26 minutes ago, TWinter said:

I'll try to get to the hanger this weekend and get a pic. I mentioned to my AP that the Power Boost was difficult to move. He checked it out at the last annual. He pointed to the cable and said that it was nearly worn through and not operating smoothly..Said that he could try to replace it then or we could wait until the next shop visit and go from there. While he had open I just took a quick look into the cowl area and saw the frayed area he was pointing out. Don't remember exactly what it looked like. Not knowing what the annual bill was going to be I passed on the repair then knowing I would be back after New Year for the light install. Drives me nuts knowing something is not 100%. Just thought I would try to source the cable and be ahead of the game.

I'll try and see if I can get a pic over the weekend.   

 

-Tom

Tom, 

If I'm honest, my Ram Air cable looks pretty lousy, but it functions beautifully.  The plastic over the coil shield has long been removed from the section that's in the engine compartment; for this reason the cable is easily lubed (though I'm not recommending removing the cover). My cable moves smooth enough for me to actuate just by reaching in when leaning against the wing. Prior to hanging my engine in 2010 it was almost a 2 handed operation. Detailing the routing and giving it a thorough lube made it feel if not look new again.

[TWinter]

1 hour ago, Shadrach said:

Tom, 

If I'm honest, my Ram Air cable looks pretty lousy, but it functions beautifully.  The plastic over the coil shield has long been removed from the section that's in the engine compartment; for this reason the cable is easily lubed (though I'm not recommending removing the cover). My cable moves smooth enough for me to actuate just by reaching in when leaning against the wing. Prior to hanging my engine in 2010 it was almost a 2 handed operation. Detailing the routing and giving it a thorough lube made it feel if not look new again.

Thanks and sounds good. I'll probably pull the cowl this weekend and really take a better look. Might just need a good "look-over". I should have checked it more carefully when he was pointing it out during annual, but they were just getting things buttoned up after annual (seems like there are always a lot of annuals lined up in the fall). I might go ahead and put the new light in this weekend. The light needs a second power run and the switch changed out to a three way. On/Off/Wig. I can handle the RR of light and get a good look while I've got it opened up and go from there.  I'll have him run the new light wiring, the log entries and sign-offs next week when I take it over. I'll get a better idea of what I have or don't have..

Thanks

 

 

-Tom

[Yetti]

I would think the "fraying" is the outer sheath coming unwound.  Should be able to wound it back up and maybe a small hose clamp over the end.   On mine the clamp on the vent housing keeps the outer sheath all wound up.

[garytex]

Mc Farland has a drawing for a replacement modified at my mechanic's request to change from a solid wire core with a bug nut to a y shaped end that attaches with a small nut and bolt to the actuating end.  This is the fix we did, and works great, and obviates the work harden/break off cycle with the solid wire core.   

[TWinter]

Found the culprit this afternoon. Looks like the fray was just the outer wire stranding that I could see prior. The center core wire had pulled loose from the lock nut/bolt that holds it in place. Awfully tight up there. A little bent, but repairable..Thanks for the info. Good functional design, but I could think of better ways it could have been done,

[Shadrach]

3 hours ago, TWinter said:

I could think of better ways it could have been done,

You can say that again!  Oddly, my 67 has a coil style cable cover, not woven like yours.

[Shadrach]

13 hours ago, garytex said:

Mc Farland has a drawing for a replacement modified at my mechanic's request to change from a solid wire core with a bug nut to a y shaped end that attaches with a small nut and bolt to the actuating end.  This is the fix we did, and works great, and obviates the work harden/break off cycle with the solid wire core.   

Could you please post a pic of the installation the next time you're in there?

[DrBill]

if you lose the ball I have more (from McMaster Carr)!!

Bill

 

[Yetti]

Looks like the cable ferrule slipped off the outer sheath.   Frayed knot.

[TWinter]

Well "Boost" is functional again. There was enough slack in the cable to be able to trim the fray back and reattach the center core to the locking bolt and re-secure the cable. Some lube while it was all opened up. Working well with full range of motion. The inside contact switch for the "Boost" light still needs some very minor adjustment, the boost lever has to be  pushed to the extreme top for the light to go off. All seems to be working as it should. Maybe I'll be able to gain that 1" of manifold pressure now.  

 

 

-Tom

[garytex]

On February 21, 2016 at 11:22 PM, Shadrach said:

Could you please post a pic of the installation the next time you're in there?

Sure, may be a while, plane down for OH and paint

[FlyingDude]

On 2/20/2016 at 11:09 AM, garytex said:

change from a solid wire core with a bug nut to a y shaped end

Could you please share it? Thank you