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  #1  
Old 10-08-2021, 02:10 PM
SteveHicks SteveHicks is offline
 
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Default RV14 EXP119 Mixture Control

Has anyone installing the EXP119 in the RV14 had an issue with the mixture cable being too long? I have the CT RED MIXTURE 54 cable as standard, with the WD-00110 IO-390C CABLES BRACKET attached as per the manual.

In the enclosed picture the red knob is fully forward in the cockpit. With the cable end anchored fully aft, and the MW-3M rod end screwed in as much as possible, the cable distance from the bracket to the rod end is as short as possible. In order to connect the mixture control arm, it has to be adjusted too far forward, so there is no way to comply with the “halfway point” rule, ie the control arm should be 90º to the cable at the half travel point.

The length needs to be shortened by approx 1/2" ... does anyone know if it's possible to tap the thread further on to the cable end, then trim the end so that the rod end could be screwed further on?
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  #2  
Old 10-08-2021, 02:33 PM
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DanH DanH is offline
 
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Quote:
Originally Posted by SteveHicks View Post
In the enclosed picture the red knob is fully forward in the cockpit.
Steve, you don't want the red knob to be against any stop in the cockpit. The knob should not be all the way forward against its mounting point when you're rigging the installation.

The only stop should be the one on the FM200. Same is true for the throttle cable. Both mixture and throttle should hit the FM200 stops at max and min before running out of travel at the cockpit end.
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  #3  
Old 10-08-2021, 02:42 PM
Ron B. Ron B. is offline
 
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I'm awaiting the remaining two MW-3M rod bearings from Van's (only one comes with the kit, go figure). They should be here soon and we will see if we have the same issue.
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  #4  
Old 10-08-2021, 03:23 PM
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rvbuilder2002 rvbuilder2002 is offline
 
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Quote:
Originally Posted by DanH View Post
Steve, you don't want the red knob to be against any stop in the cockpit. The knob should not be all the way forward against its mounting point when you're rigging the installation.

The only stop should be the one on the FM200. Same is true for the throttle cable. Both mixture and throttle should hit the FM200 stops at max and min before running out of travel at the cockpit end.
What Dan said.
There should always be a cushion gap (I use about 3/32" as a minimum to account for potential slop cause be wear over time) on controls so that you can visually confirm the the stop at the other end is what is limiting travel.

If you do that it looks like it will be fine. Don't expect the cable barrel to be exactly centered on the bracket.... The length tolerance when they make the control cables is pretty big.
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  #5  
Old 10-08-2021, 03:23 PM
SteveHicks SteveHicks is offline
 
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Quote:
Originally Posted by DanH View Post

The only stop should be the one on the FM200. Same is true for the throttle cable. Both mixture and throttle should hit the FM200 stops at max and min before running out of travel at the cockpit end.
Thanks Dan ... I should have mentioned, the picture showed the geometry with the cockpit red knob fully forward less a 1/16" Cushion Gap as stipulated in the manual.

I think I'll remove the cable and check it is actually 54" long ... I just assumed it was correct, since it had a CT RED VMIXTURE 54 label.
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Old 10-08-2021, 03:49 PM
SteveHicks SteveHicks is offline
 
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Quote:
Originally Posted by rvbuilder2002 View Post
The length tolerance when they make the control cables is pretty big.
Scott, do you think my cable could be at the top end of the tolerance then ... it is at least 1/2" too long. I just can't shorten it anymore since the rod end is completely wound on up to it's thread depth, and the cable anchor point is fully aft at the bracket?

The pictures show an ideal fully rich position for the FM200 mixture lever, and the rod end too far ahead by over 1/2". The other picture shows the cushion gap in the cockpit with that geometry.

Thanks for taking a look for me.
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  #7  
Old 10-08-2021, 04:36 PM
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I don't know.
Incorrect overall length wont have any effect on the fit between the bracket and the mixture arm on the servo though... this will be close to the same for all cable lengths.

One thing you could do is increase the cushion gap a bit.

Another would be to trim a bit off of the length of the threaded portion where the rod end attaches so that you could run the jam nut all the way back to the start of the threads.

I haven't heard about anyone else having this issue so I am not sure what the root cause is. You could give our tech. support a call and see if they have had anyone else with this and see what the resolution method was.
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  #8  
Old 10-08-2021, 05:45 PM
Ron B. Ron B. is offline
 
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Is it possible to adjust the mixture arm on the fuel servo?
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  #9  
Old 10-08-2021, 06:57 PM
Bavafa Bavafa is offline
 
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I installed mine and it looks very much like Steve's, picture above. The rod end bearing is screwed all the way and I have a couple or more threads left on the bracket but it is working as expected without any issues. I have about 1/8" maybe a little less cushion at the knob.

Do you have two washers between the rod end bearing and the arm. The two washers keep the rod end bearing a bit farther away.

Hope this helps.
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Last edited by Bavafa : 10-08-2021 at 07:01 PM.
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  #10  
Old 10-09-2021, 04:49 AM
SteveHicks SteveHicks is offline
 
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Thanks for the tips/advice chaps.
When I contacted Vans Tech Support earlier yesterday they had not heard of anyone else having this issue. Maybe my cable was just a bit longer than normal between the bracket attachment and the end, which is the only cable factor which effects this, as Scott pointed out.

But in case anyone else has a similar cable, I found that by trimming off enough cable thread to allow the rod end to completely screw on up to the jam nut, by having the thread just showing on the bracket, and by accepting a bigger than necessary cushion gap at the knob, I was able to get it all working with the FM200 Arm in the optimum position.

The attached pictures show the result.
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