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Mixture Push/Pull Alignment Issue

CharlieWaffles

CharlieWaffles

Well Known Member
I've got a stock set up with the YIO-540 from Vans with the stock Fuel Servo. I just connected my push pull cable and secured it to the stock push/pull cable mount adapter between the servo and the engine sump. When I attempt to use the stock hardware (bolt, washers, etc..) the bearing is at a severe angle to the mixture arm. Once this is torqued down the rod end bearing is pinched into place and causes a great deal of friction. The only way I found to eliminate this friction was to use a longer bolt and add some AN960-10 washers that are in smaller diameter right up against the bearing surface. The larger safety washers are still there, just farther from the bearing.

Has anyone else had this issue? Other options to resolve this? The first two pictures are the stock hardware setup. The third is the configuration I used to eliminate the friction.

WP_20130116_003_zpsb26df8a0.jpg


WP_20130116_006_zpsbb274a68.jpg


WP_20130116_016_zpscfe2fb0d.jpg
 
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Mark,

Is there a way to modify or bend the bracket leading the cable in, or is the inlet hose in the way? Since these are factory parts, will be informative as to Van's take...

Jerry
 
Not sure an adjustment on the bracket would help. If I could man handle it to twist the mount point, the bearing would be at an even getter angle. Short of making the mount wider which would push the mount to be more in line with the mixture, I don't think anything could be done there. If the bend in the mixture arm come off of the servo wasn't there and came straight down it would line up better. Not sure if there is an option to do that though.
 
Throttle?

Try trading your mixture lever with the throttle lever if the throttle is straight & not offset. Thats how we fix it on our IO360.
 
You need the bent one.

A bit of tube or some washers is the answer.

Make sure you get full travel and allow for some slack in the cable for when the engine pulls forward on the mounts.
 
This is a common problem. If you search the threads you will find lots of discussion and various solutions. I ordered my servo with the mixture control reversed, put on a shorter offset arm, modified the bracket by adding an extension, moved the fuel inlet to the opposite side and the outlet to the back. That's one way for th IO360. Not sure what other issues might be with your engine.
 
Mine does too

Mine looks just like your first photo. Works fine for a year now.
RV101947.jpg
 
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9GT said:
Looking at that setup gives me the heebeegeebies. And whats with the fuel supply line resting in contact with the exhaust collector? I don't care if its fire sleeved!
Click to expand...

I'm gonna guess the fuel supply line was rearranged before the airplane started flying.
 
I spoke with Vans and it looks like I have the wrong washers on my assembly. There should be some much smaller O.D. washers on either side of the bearing. I picked some up and will try them. They look like they should allow the bearing to rotate much better at the angle I am seeing.

Also, I spoke to Vans and they were not aware of this alignment issue (big surprise?). They said they used a bendix FI as that was all that was available at the time so they haven't looked at the issue with the silverhawk.
 
Ok, the washers were the issue. I switched the washers out for much smaller OD washers. I had incorrectly put too large of washers next to the bearing and that was causing the friction due to the angle. I swapped them out for the right ones and now have full motion with no friction.

WP_20130117_003_zps1e410378.jpg
 
9GT said:
Looking at that setup gives me the heebeegeebies. And whats with the fuel supply line resting in contact with the exhaust collector? I don't care if its fire sleeved!
Click to expand...

That was taking during the build process on Tim's plane. I think he has everything working okay since he now has over 900 hours in it.
 
Strasnuts said:
That was taking during the build process on Tim's plane. I think he has everything working okay since he now has over 900 hours in it.
Click to expand...

Looked like a permanent install based on how the builder had fabricated a clamp on the air intake coupling that the fuel supply line was clamped to. May have been just a pic of a temporary mockup.
 
Don't believe everything you read. Many pictures on the site are taken DURING the build and that picture in no way represents how things were once assembled. I don't even know why that was introduced as some sort of "fix" for the problem. That's just a picture taken as things are getting routed.....and to imagine that someone would put a fuel line on the exhaust like that is just plain ridiculous.

Without context, photos mean nothing in many cases.
Tim

PS: Yes, 920 hours and I haven't exploded or had my mixture bind.
 
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I for one do not think Tim's post is "uncivil".
Furthermore, he has every reason to be upset, as apparently someone re-posted a photo which belongs to him, without asking permission.

Bob
 
Guys, don't worry about it. The guy made a mistake and linked to a picture that was just taken a couple months prior to completion. He isn't currently building a kit, so he didn't know entirely what he was looking at, and was just trying to help. It takes a while to get all the hoses and cable routings secured in places that work well, and keep all hoses and cables from being near exhaust or rubbing engine mounts or other things, so it was just a work in progress and he didn't know that. It didn't bug me at all until I started seeing that more and more people got led into the weeds and thought that was how it was when flying.

My point is, make sure you get context from the actual picture taker when looking at things like this, because these forums can lead you into the weeds real easily.

Case in point: on the RV-14 the plans have had multiple errors so far, with drawings depicting things that are leftover from the RV-10, but changed in the RV-14. I was going along fine, having built an RV-10 wing before, until I had to scratch my head a few times on one area because plans and drawings didn't match up. Then I stumbled on ONE guy's post on VAF's 14 forum (and I don't even know that the guy is even BUILDING one himself), that made some comment that was totally wrong, but led me to start to think down that path. Long story short, I had to buy $50+ in wing ribs and shipping because I started to listen to something on the forum, from someone who probably didn't have a clue, because he only built a 10 and wasn't building a 14. Today, I've finally got the new parts all prepped and am caught up. It's not his fault, as it's MY responsibility to thoroughly review things until they are clear, but Van's didn't make it easier by having improper drawings in the plans, and this guy didn't make it easier by making comments about things he doesn't understand.

So take it all with a grain of salt, and I don't think "Trust-but-verify" even applies....better to just plain not trust.

BTW: I wasn't real angry, just a little irked that others were starting to make improper assumptions, and the concepts were so ridiculous that they made ME look stuipd. But I agree, I didn't think it was un-civil. If you do, then I'm sorry.

Oh, and my cable connection is per-plans, and works fine. Also, you will want to put some heat shield around the mixture cable, and the fuel line in that region. Even though my hose and cable are a few inches from the exhaust, it's far safer with some form of silver heat shield, and keep those lines as far as you can from the hot stuff.

cables06.jpg


This one is more like the finished product:
Mixture_Side.jpg


Tim
 
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