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  #21  
Old 06-25-2013, 08:40 AM
Omega232Devils's Avatar
Omega232Devils Omega232Devils is offline
 
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Default Just an observation

Steve,
Just an observation here. (I have dual P-Mags so I am following this thread)

My observation is you have convinced yourself that you know what the problem is, but all your diagnosis tells you it is fine. You seem to be ignoring others recommendations (the ones you asked for) by validating "nothing has changed" and "it WAS working fine". Everything works fine, right up to the moment it breaks!

I am not trying to be sarcastic, but would suggest you take a moment and back away from the problem and read the suggestions. Then systematically step through them from plugs to PMags till you find the problem. I know it is frustrating, but your frustration is just going to blur the solution.

IMHO,

Dan
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  #22  
Old 06-25-2013, 09:50 AM
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schristo@mac.com schristo@mac.com is offline
 
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Default In flight mag check...

A couple of thoughts... a ground run mag check is a course measure to ensure that you don't have an obvious ignition issue. 1,400 or 1,000 RPM is low for a ground run... I do mine at 1,700-1,800

A better practical test of your ignition system is an extended inflight mag check. It is good to test and familiarize yourself with how the engine operates on a single mag and will provide more meaningful information.

Also, since you have one ignition firing the top and the other on the bottom you should expect some difference in performance between the two... Best evaluated if flight at cruise power. I have mine set traditionally with half top and half bottom for each PMag.
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  #23  
Old 06-25-2013, 09:59 AM
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ColoRv ColoRv is offline
 
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Default

The suggestion of plug wires getting swapped on the Pmag seems the simplest response that would have this effect. Personally, whether I'm wrenching on motorcycles, race cars, weedeater or airplane my first assumption if a replaced part is running wrong is assembly error. While it has certainly happened where the part was faulty...the most common issue is I swapped something simple. Usually that occurs in the "cruise mode" stuff where I'm not thinking about it much and just putting stuff back on. Check that every plug wire is where you want it and double check the wiring connections are good in the screw down block. Then, run through the website troubleshooting step by step. If that doesn't work....punt (call Emag) and send them back or swap with known good ones.
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Last edited by ColoRv : 06-25-2013 at 10:03 AM.
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  #24  
Old 06-25-2013, 11:28 AM
cguarino cguarino is offline
 
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Default I did it.

Quote:
Originally Posted by ColoRv View Post
The suggestion of plug wires getting swapped on the Pmag seems the simplest response that would have this effect. Personally, whether I'm wrenching on motorcycles, race cars, weedeater or airplane my first assumption if a replaced part is running wrong is assembly error. While it has certainly happened where the part was faulty...the most common issue is I swapped something simple. Usually that occurs in the "cruise mode" stuff where I'm not thinking about it much and just putting stuff back on. Check that every plug wire is where you want it and double check the wiring connections are good in the screw down block. Then, run through the website troubleshooting step by step. If that doesn't work....punt (call Emag) and send them back or swap with known good ones.
After I had my PMags checked, I installed two wires wrong and it acted a lot like this. Retarding the timing a couple of degrees should not even be noticeable. I think the wires are crossed or you are not timing it where you think you are. The marks on the front of the fly wheel are easier to use. I would cross reference them. Remember it should be on the TDC mark not the mag timing mark. BTW, is the mark on the back of the flywheel TDC or a mag timing mark? If there are both, make sure you are using the TDC one. You do not time PMags like traditional mags. Please let us know what you find.
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  #25  
Old 06-25-2013, 12:04 PM
steve91t steve91t is offline
 
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Location: Huntersville, NC
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Default

Quote:
Originally Posted by Omega232Devils View Post
Steve,
Just an observation here. (I have dual P-Mags so I am following this thread)

My observation is you have convinced yourself that you know what the problem is, but all your diagnosis tells you it is fine. You seem to be ignoring others recommendations (the ones you asked for) by validating "nothing has changed" and "it WAS working fine". Everything works fine, right up to the moment it breaks!

I am not trying to be sarcastic, but would suggest you take a moment and back away from the problem and read the suggestions. Then systematically step through them from plugs to PMags till you find the problem. I know it is frustrating, but your frustration is just going to blur the solution.

IMHO,

Dan
Right, but some common sense can tell us where to look. Also, something that I can't really describe very well is the way the engine was running. A crossed or bad plug wire is obvious. EGT, CHT, sound...that alone absolutely rules out a bad wire or plug, right? Sometimes sitting back and thinking is better than just testing stuff that we know is working.

Quote:
Originally Posted by schristo@mac.com View Post
A couple of thoughts... a ground run mag check is a course measure to ensure that you don't have an obvious ignition issue. 1,400 or 1,000 RPM is low for a ground run... I do mine at 1,700-1,800

A better practical test of your ignition system is an extended inflight mag check. It is good to test and familiarize yourself with how the engine operates on a single mag and will provide more meaningful information.

Also, since you have one ignition firing the top and the other on the bottom you should expect some difference in performance between the two... Best evaluated if flight at cruise power. I have mine set traditionally with half top and half bottom for each PMag.
I usually also do my check at higher RPM, but we've also done it lower and never got much of a change. I believe my dad did wind it up once while doing a check, above 1500 and there was no change. I agree we could find out a lot more if we flew it.....I ain't flying it until we figure out a little more. Plus, timing issues can destroy engines. Really no reason to fly it right now when we have the problem on the ground.

Quote:
Originally Posted by ColoRv View Post
The suggestion of plug wires getting swapped on the Pmag seems the simplest response that would have this effect. Personally, whether I'm wrenching on motorcycles, race cars, weedeater or airplane my first assumption if a replaced part is running wrong is assembly error. While it has certainly happened where the part was faulty...the most common issue is I swapped something simple. Usually that occurs in the "cruise mode" stuff where I'm not thinking about it much and just putting stuff back on. Check that every plug wire is where you want it and double check the wiring connections are good in the screw down block. Then, run through the website troubleshooting step by step. If that doesn't work....punt (call Emag) and send them back or swap with known good ones.
I've done it as well...more often than I care to admit. But we spent about 4 hours installing these mags yesterday. We both checked everything several times before the initial start. Then many times after we realized something was wrong. If the plug wires were crossed, we would loose half the engine.

Quote:
Originally Posted by cguarino View Post
After I had my PMags checked, I installed two wires wrong and it acted a lot like this. Retarding the timing a couple of degrees should not even be noticeable. I think the wires are crossed or you are not timing it where you think you are. The marks on the front of the fly wheel are easier to use. I would cross reference them. Remember it should be on the TDC mark not the mag timing mark. BTW, is the mark on the back of the flywheel TDC or a mag timing mark? If there are both, make sure you are using the TDC one. You do not time PMags like traditional mags. Please let us know what you find.

So the reason I found true TDC on #1 was to verify the timing marks on the flywheel instead of just assuming they were correct. The TDC mark on the back of the flywheel lined of perfectly with the seam of the case along with a black sharpie mark over one of the holes of the starter. We also saw the mag timing mark and did not use that one.
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  #26  
Old 06-25-2013, 12:23 PM
steve91t steve91t is offline
 
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My dad contacted E-mag and Eric agrees that we are indeed timing the mags correctly. As you guys suggested, Eric wants us to pull the prop through to make sure the green light illuminates at TDC. That and run the engine with the MP line disconnected and see how the effects the run up. If we are still having issues, he wants us to send them back to him and have him check the programing. He said sometimes battery chargers can cause problems if the mags are on while it's turned on. We did charge the battery, but didn't have the master or mags on while it was plugged in. But again, he said something could be wrong with the programs.

When the engine is run without the MP line hooked up, do we have to cap it off on the engine or mag side? Also, because it isn't advancing, it should run really bad, right? Spark too retarded? Possibly the MP line upstream of where I was blowing is housing a spider or something? Doing a mag check with this line disconnected will rule this out.

I know I'm shooting down a lot of your ideas, and I don't want to seem like I'm not appreciative. But if you guys heard this engine running, you would understand that it isn't a plug wire issue.

Let me ask you guys this, what indications would you get if we messed up the plug wires? On one mag, two cylinders would not fire, if not all 4. Right? That's why I'm telling you guys that it's something other than plug wires.

One thing that I've learned is when you change a part and then there's a problem, it's probably whatever you were messing with, not something else that magically failed during the work.

Now, my dad is going down there probably tomorrow to try some of the things we talked about.


Since these mags are so easy to pull off, after my add does the tests tomorrow, he'll pull the mags and send them back to have them checked. Now, if they come back and found no problems, and it still has an issue durning a mag check, we will have no choice but start from the plugs and work our way back.

Last edited by steve91t : 06-25-2013 at 12:27 PM.
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  #27  
Old 06-25-2013, 12:56 PM
steve91t steve91t is offline
 
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Default

I just want to say again, thank you guys for all of your help. It's great to see so many people here to help. I hope I get to return the favor someday. I'll let you know what we find.
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  #28  
Old 06-25-2013, 12:59 PM
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Brantel Brantel is online now
 
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Default

Quote:
Originally Posted by steve91t View Post
When the engine is run without the MP line hooked up, do we have to cap it off on the engine or mag side? Also, because it isn't advancing, it should run really bad, right? Spark too retarded? Possibly the MP line upstream of where I was blowing is housing a spider or something? Doing a mag check with this line disconnected will rule this out..
If you run it with the MP line disconnected (local atmospheric pressure), the Pmag will think it is at a high MP and therefore won't advance the timing at all. In this case it will run just like a regular Mag firing at about 20° BTDC. This alone will not cause the engine to run rough.

If you connect a laptop to the Pmags and use the EICAD software, you can use the tools available to help in your troubleshooting.

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Last edited by Brantel : 06-25-2013 at 01:02 PM.
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  #29  
Old 06-25-2013, 01:02 PM
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Omega232Devils Omega232Devils is offline
 
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Default MP line

Just pull the MP line. I believe you said you have a 'T' from the MP cylinder line to the P-Mags. Just disconnect that line. The engine should not run rough at all. Disconnecting the MP line will prevent the P-Mags from advancing the timing, essentially turning them into regular mags firing at 25 deg BTDC.

As for the plug wires, I am sure you are convinced they are not they problem and you are probably correct, but to save you headache here and satisfy guys trying to help you. You could ohm check them, and verify they are connected correctly once more and post those results. ie "We ohm checked all 8 plug wires and ensured they were reinstalled properly.....problem still persists"

One question and this is a shot in the dark, did you change orientation of the P-Mags when you re-installed them? The orientation does not matter, but if lets say you rotated the P-Mag 180 degs and then reinstalled the plug wires according to the old orientation just by looking at the back of the P-Mag vice its original orientation, you could have the wires appearing they are on correct, but in fact are on opposite cylinders.
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  #30  
Old 06-25-2013, 01:10 PM
steve91t steve91t is offline
 
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Default

Quote:
Originally Posted by Omega232Devils View Post
Just pull the MP line. I believe you said you have a 'T' from the MP cylinder line to the P-Mags. Just disconnect that line. The engine should not run rough at all. Disconnecting the MP line will prevent the P-Mags from advancing the timing, essentially turning them into regular mags firing at 25 deg BTDC.

As for the plug wires, I am sure you are convinced they are not they problem and you are probably correct, but to save you headache here and satisfy guys trying to help you. You could ohm check them, and verify they are connected correctly once more and post those results. ie "We ohm checked all 8 plug wires and ensured they were reinstalled properly.....problem still persists"

One question and this is a shot in the dark, did you change orientation of the P-Mags when you re-installed them? The orientation does not matter, but if lets say you rotated the P-Mag 180 degs and then reinstalled the plug wires according to the old orientation just by looking at the back of the P-Mag vice its original orientation, you could have the wires appearing they are on correct, but in fact are on opposite cylinders.
We traced the wires from the plug back to the mag to make sure that wire went to the proper spot (either top of bottom of the mag, per the instructions).
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