Manual trim cable too short!!!

I have a fuel injected engine on a RV7A, so I installed the high speed fuel pump just forward of the manual trim knob.

Now I find the manual trim cable lacks about 2 to 3 inches from mating with the manual trim knob if I position it in front of the doghouse for the fuel pump. The plan (OP-21) shows making a notch in the front edge of the doghouse and running the cable in front of and over the top of the doghouse.

I tried everything I could to get some additional slack out of the cable in order for it to match up with the knob by doing it the way the plan shows.

I called Van's and they said they could order me an RV8 cable at 191" (mine is 181") along with $135.00 with no refund for the old cable because it is over several years old (still never flown). That will leave me with a cable too long and by the time I get it and re-install the new cable, it will probably keep me from finishing my airplane this year.

Has anyone had this problem and if so how did you fix it?

Any area from the trim tab and aft fuselage forward where you can change the trim cable routing to go more straight to get you some more length?

Re: Trim Cable

I have the manual trim for my RV7
The cable sent with the kit was too short.
Sent it back to vans for the longer one.
The replacement cable is plenty long now.

Call Vans

RV-8 trim cable is the standard fix

Yep. That's the standard deal. The RV-7 manual trim calbe is not long enough to be routed around the high pressure fuel pump on its way to the elevator. I had the same experience, and ordered an RV-8 trim cable from Van's to solve the problem.


So, I also have a surplus RV-7 manual trim cable, and my plan is to sell it. I expect someone will need one.

Carl,

I have not done mine yet but plan to follow what a friend of mine did on his -7. He drilled a hole in the forward face of the "doghouse" large enough for a grommet and the trim cable. The cable can thus cut the corner and save a few inches. It saved enough to work with the standard cable. The cable routes in between the fuel lines in front of the fuel pump inside the doghouse.

You'll need to work out for yourself the right place to drill the hole.

Best of luck,

Steve
RV-7 (working FWF and panel)
West Sussex
UK

Solution

Carl

Two solutions

1) Buy an RV8 cable

2) Or as Steve suggest drill a hole in the top of the fuel pump cover and route it through. The hole has to be large enough to take the cable end (disconnect the knob section).

If you want a photo I'll take one next time I'm at the plane and post it.

Simple solution and it actually doesn't look out of place

Peter

Thanks

I appreciate your help.

I was able to do as you said and route the cable between the fuel lines of the fuel pump. I will make the hole into the face of the pump cover later as I am trying to finish the airplane for inspection. I suspect the cover should be off for the inspection anyway.

I thank you all for your support!

Onward with the instrument panel installation

Here's another option - one of these might work:
http://www.aircraftspruce.com/catalog/appages/extcontrols.php

I am planning on a minor enhancement to the simple hole in the fuel pump cover. I'm going to cut a slot just a little wider than the trim cable from the hole to the forward edge of the fuel pump cover. Then I'll fabricate a small cover plate for the slot which will be held in place using #6 screws/nutplates.

This will facilitate removal of the fuel pump cover without the need to tamper with the trim cable.

Steve

Not after 2 years.

Vans won't replace mine since it is over two years old. I seem to recall, when I purchased my kit in 2002 they would replace parts in like new condition as long as the parts were like new and they could still sell them.

I am not complaining though because they did replace a exhaust system a couple of years ago.

It is really not a problem removing the fuel pump since the cable will come apart very easily near the knob end.