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  #11  
Old 05-04-2018, 05:29 PM
polkaking27 polkaking27 is offline
 
Join Date: May 2017
Location: murray
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Thanks guys, It sounds like things aren't normal and I need to get them checked out.

Yes it does have the adjustable rudder pedals

And I haven't noticed if I'm pushing on the stick when I'm on the brakes. That is completely possible. I'll have to check that out.
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  #12  
Old 05-04-2018, 07:12 PM
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RV8Squaz RV8Squaz is offline
 
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Quote:
Originally Posted by RV6_flyer View Post
IF your carb idle mixture is too lean, you can also get a low or no mag RPM drop. IF you do a mag check on an airplane with dual mags that has the carb set correctly, one can pull the mixture out some (lean the engine) and get very little to no mag drop on a lean mixture.
I agree with Gary. If you’re not already doing your mag check with the mixture full rich, give that a try first. Also to rule out if a mag is not being grounded, turn off both ignitions momentarily by either the key switch or toggle switches. The engine should quit momentarily. Do this at idle.

BTW, it was nice to meet you last week Gary.
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  #13  
Old 05-04-2018, 08:23 PM
polkaking27 polkaking27 is offline
 
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I'm pretty sure I have had the mixtrue full rich, but I'll make sure thats the case tomorrow. Thats a good thought.
Will you guys walk through this with me? From what I understand the mags are being grounded when I turn to ignition switch to them. So essentially when I turn the key to L I'm actually grounding the L mag and running only on the R mag, essentially testing this one. When I turn the key to the off position the engine will die almost immediately. I assume that is because both mags are being grounded therefore there is no longer a spark at that point. So... if I see no drop when switching between L then both then R then it seems like it may be the ignition switch. Is that a correct path of thought. If one of the P-leads were disconnected then turning the switch to off would stop the engine, right???

Next Q- Could the aileron resistance be the rudder cables tightening up against the aileron torque tubes under the floor boards? Also, it has the rear rudder pedals installed... could that cause anything?
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  #14  
Old 05-04-2018, 08:30 PM
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Sam Buchanan Sam Buchanan is offline
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Quote:
Originally Posted by polkaking27 View Post
I'm pretty sure I have had the mixtrue full rich, but I'll make sure thats the case tomorrow. Thats a good thought.
Will you guys walk through this with me? From what I understand the mags are being grounded when I turn to ignition switch to them. So essentially when I turn the key to L I'm actually grounding the L mag and running only on the R mag, essentially testing this one. When I turn the key to the off position the engine will die almost immediately. I assume that is because both mags are being grounded therefore there is no longer a spark at that point. So... if I see no drop when switching between L then both then R then it seems like it may be the ignition switch. Is that a correct path of thought. If one of the P-leads were disconnected then turning the switch to off would stop the engine, right???

Next Q- Could the aileron resistance be the rudder cables tightening up against the aileron torque tubes under the floor boards? Also, it has the rear rudder pedals installed... could that cause anything?
You have it backwards. If a mag is grounded, it won't fire. To test the L mag, the R mag is grounded when the switch is in the L position which kills the R mag.

If a P-lead is disconnected, you can't turn off that mag.
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  #15  
Old 05-05-2018, 12:15 AM
rv8ch rv8ch is offline
 
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Quote:
Originally Posted by polkaking27 View Post
...Next Q- Could the aileron resistance be the rudder cables tightening up against the aileron torque tubes under the floor boards? ...
Yes, this could be happening, and like others have said, please check this or get it checked before you fly again - not something to be messed with. With an electric screwdriver (if the builder used screws in the floorboards) it will take about 15 minutes to get them off. If they used pop rivets, it's probably 20 minutes of drilling. Have a shop vac handy to slurp up the bits after drilling.
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  #16  
Old 05-05-2018, 07:38 AM
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N941WR N941WR is offline
 
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Do you have a digital or analog RPM display and do you have some type of electronic ignition?

Electronic ignitions typically have very little mag drop and if you have an old style analog tach, you may not notice an RPM drop.
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  #17  
Old 05-05-2018, 08:01 AM
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Sam Buchanan Sam Buchanan is offline
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Quote:
Originally Posted by polkaking27 View Post

As far as the ignition goes, I am running dual mags.
Quote:
Originally Posted by N941WR View Post
Do you have a digital or analog RPM display and do you have some type of electronic ignition?
OP has dual mags per his quoted post.
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  #18  
Old 05-05-2018, 09:51 AM
polkaking27 polkaking27 is offline
 
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Quote:
Originally Posted by Sam Buchanan View Post
You have it backwards. If a mag is grounded, it won't fire. To test the L mag, the R mag is grounded when the switch is in the L position which kills the R mag.

If a P-lead is disconnected, you can't turn off that mag.
Thanks Sam, I did have it backwards. What you said makes more sense. but would my theory still be correct? since turning the switch to off will kill my engine then the P-leads must be connected correctly. Should I be looking at the ignition switch.

I headed to the airport now to pull the floorboards and check this out.
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  #19  
Old 05-05-2018, 10:56 AM
polkaking27 polkaking27 is offline
 
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Ok so I just pulled up the floor board and found that when I engage the rudders the cables are hitting the aileron torque tubes. The rudder cables are in a sheath at this point so I assume that Van’s has expected this rubbing to take place. The airplane only has 180 hours on it and I imagine the cables are still pretty tight. Maybe as the years go by those loosen up a bit. Is this the way things are supposed to be routed under there? It looks like that’s the only way it could go to me. I imagine this will just be an item at each annual to check and make sure there is no wear.
Like I said in my original post, this friction doesn’t impede any aileron movement, I can just feel it touching something. What do y’all think... safe???

https://photos.app.goo.gl/xSYXqmT9pKJbKRy4A
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  #20  
Old 05-05-2018, 12:17 PM
ILikePike ILikePike is offline
 
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The rudder cables should pass through the spar on top of the aileron pushrods. Check the plans carefully for this area. IMO interference here is unacceptable and should be corrected.
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