throttle cable length/routing/tension

[andrew phillips]

My throttle cable is the shortest length possible between the panel and the engine bracket. The route it takes does not allow for an easy spot to clamp between the panel and firewall. My panel is very rigid so I don't know if the midpoint clamping is necessary. The cable operates smoothly but I am not sure if it would be better to have a longer cable that would take on some more graceful curves. Any advice?

[Ironflight]

Hi Andrew,

Remember that the engine is going to move some.....I would be a bit nervous with anything connected to it being "in tension" - you really need a little bit of slack (graceful curves, as you say) to make sure that you aren't putting a strain on things. I had trouble opening the larger version of your picture, but going just on your words, I'd probably go for a bit longer cable.

Paul

[RV7Guy]

Fitting the cables is a little frustrating. I'd be curious as to how many cables get returned for new ones and how many times!!!! I had two exchanges. My neighbor is on three.

I agree with Paul. You need a compromise between to tight and to loose. If the linkage is tight, you are risking binding and potential chafing and breakage. Remember this is a cable inside there. To loose and the arcs will eat up the travel and you may not be able to get full throw.

I can't get the big photo to open either, but from what I can see, I'd say a couple of inches longer on the cable will give you some latitude for fastening without binding.

It goes without saying, that this is an area that needs to be as perfect as possible.

[Ken]

Small bend is good to eliminate cable tension. More bends and/or tighter radii will increase friction in cable. In a previous aircraft without a friction lock I added a bend to give me more friction.

Ken

[DarylT]

I got the big picture open and the cable looks like too straight of run. They already look strained. Remember you need to run those thru a grommet in the cover panel as well.

[Steve]

It was hard to tell from your picture, but I don't see the sub panel (with engine cables) attached to the bottom of the instrument panel. That would effectively lengthen the cables approx 2".
Vans does sell longer-than-stock cables, too.
Steve