Jeff R
Well Known Member
I have an interesting story to report regarding my first engine start. To begin, I purchased the experimental IO-320 through Van?s way back in 2008. It has the standard Slick magnetos and was run by Lycoming prior to shipment to me. It was not until last Friday that I finally attempted to start it. With assistance from some of the local airport bums, I mean, experts, we got the mags timed and verified fuel flow, then tried a start. Nothing. The prop just wind milled ? no coughing or sputtering to indicate anything but the starter motor was alive.
We tried several times and, with the battery getting low, was going to finally give up but when I released the starter for this last time, it kicked in! I was slow to advance the mixture and it quickly died, but at least it was alive. However, further attempts to start were unsuccessful and we pushed the plane back to the hanger, connecting the charger and scratching our heads.
Later in the afternoon I and my hanger buddy pulled the plane back out to try again. Again, nothing but, just as I was about to give up gain, she kicked in. I managed to keep it going, leaned her out a bit, and she was pretty smooth. I proceeded to run the Lycoming procedure for running new engines and all was well. However, when I did the mag check, the engine died when set to run on the Left mag. Hmm. I switched back to Both and it recovered, and it ran on Right, but running on Left would totally kill it with no signs of sputtering or backfiring.
After thinking about it, it seemed obvious that the left mag was bad and that was why it was so difficult to start, as that is the mag that has the impulse coupling. It was then also obvious as to why the engine would not start when the starter was activated, as the ignition switch grounds out the right mag. Thus, when the ignition was released and went back to Both, the right mag would then be active and would occasionally generate enough of a spark to kick the engine into running. Not all the time, but every once in a while.
The big question now, of course, is why did a magneto that had only been run by Lycoming back in 2008 fail? Was it bad at purchase? Did if fail over the last 3-1/2 years just sitting on the engine, unused?
To verify for sure that the mag was indeed bad (none of us could believe a basically brand new mag could fail), we did two things. One, we disconnected the P Lead and actually got the engine to start on the Right mag but, again, when set to the Left mag, it died. With a good mag, it would have been hot all the time and would not have died. Two, we pulled the plugs, spun the engine with the starter and, with a spark plug lead held near the engine case, drew no spark. This totally ruled out that the mag was mis-timed.
Bummer. But, I was going to install a PMAG anyway. Still, I have an unused mag that is bad and is out of warranty. Can anyone recommend a good mag repair shop??? Or explain what may have happened?
Jeff
We tried several times and, with the battery getting low, was going to finally give up but when I released the starter for this last time, it kicked in! I was slow to advance the mixture and it quickly died, but at least it was alive. However, further attempts to start were unsuccessful and we pushed the plane back to the hanger, connecting the charger and scratching our heads.
Later in the afternoon I and my hanger buddy pulled the plane back out to try again. Again, nothing but, just as I was about to give up gain, she kicked in. I managed to keep it going, leaned her out a bit, and she was pretty smooth. I proceeded to run the Lycoming procedure for running new engines and all was well. However, when I did the mag check, the engine died when set to run on the Left mag. Hmm. I switched back to Both and it recovered, and it ran on Right, but running on Left would totally kill it with no signs of sputtering or backfiring.
After thinking about it, it seemed obvious that the left mag was bad and that was why it was so difficult to start, as that is the mag that has the impulse coupling. It was then also obvious as to why the engine would not start when the starter was activated, as the ignition switch grounds out the right mag. Thus, when the ignition was released and went back to Both, the right mag would then be active and would occasionally generate enough of a spark to kick the engine into running. Not all the time, but every once in a while.
The big question now, of course, is why did a magneto that had only been run by Lycoming back in 2008 fail? Was it bad at purchase? Did if fail over the last 3-1/2 years just sitting on the engine, unused?
To verify for sure that the mag was indeed bad (none of us could believe a basically brand new mag could fail), we did two things. One, we disconnected the P Lead and actually got the engine to start on the Right mag but, again, when set to the Left mag, it died. With a good mag, it would have been hot all the time and would not have died. Two, we pulled the plugs, spun the engine with the starter and, with a spark plug lead held near the engine case, drew no spark. This totally ruled out that the mag was mis-timed.
Bummer. But, I was going to install a PMAG anyway. Still, I have an unused mag that is bad and is out of warranty. Can anyone recommend a good mag repair shop??? Or explain what may have happened?
Jeff
