Omega232Devils
Well Known Member
Electro Air / Jeff Rose Ign (Updated)
Hello VAF!
First the disclaimers: 1) I have searched and read everything regarding the Jeff Rose/EA ignition system here. 2) I am new to electronic ignitions and relatively new airplane. (To me at least)
Background: I purchased the plane in August of this year, 1999 Aerosport O-360-A1A, 537 TTSN. Left side Slick magneto recently overhauled 30 hours ago. Right side is old school (Gold panel with coils and DIU combined) Jeff Rose electronic ignition.
Problem: About 4 weeks ago, I started noticing an increase RPM drop during my magneto checks. Before the checks would be 0-10 rpm drop when running on EI only and 70-100rpm drop when running on Slick Mag only. My RPM drop quickly became 150-300rpm drop when running EI only. After cycling the power (10amp breaker switch) the ignition would 'turn on' and the engine would gain 150rpm and 'smooth out'. Another EI only check would show normal 0-10rpm drop.
Phone con w/ ElectroAir: After describing the problem with ElectroAir, they said it was a faulty switch, so I ordered a new one and put it in. (I had a local electronics store test old switch and it worked fine). New switch did not fix the problem. I called ElectroAir again and they were convinced it was a problem with the circuit board (as documented in forums here).
Problem 2: The problem gradually got worse over 3-4 flights. The EI would not 'turn on' until cycling power or running engine on Slick mag. (I can't say which it was, the cycling power or running of engine, cause neither was definitive or able to single out in testing.) I checked the timing of the EI and it was spot on. So I pulled the unit and sent it back to ElectroAir for diagnostics. I got a call this morning and the unit is running 'great' they said. They left it outside in cold Michigan weather for 2 hours and tried it again and it worked 'great'. So now where am I?
Possible solution?: I have checked the magnetic pick up sensor with my ohm meter and it passed the 600-800ohm test with 656ohms. I also did the voltage test on the sensor and it worked fine also. The Magnetic pick up sensor is the old size 3/8".
My thought is that the Magnetic pick up sensor has a short and when shorted out on the start, the sensor does not sense any RPM and thus the unit does not fire. After the vibration from the engine being run on the single mag, the sensor short is connected and picks of RPM and the unit fires. I know the sensors are prone to failure, but.... any ideas? What else could it be? What else should I look for.
In the mean time while I wait for the unit to come back from ElectroAir, I am going to change the spark plug wires. I have the Taylor 8mm wires running parallel to Autolite 386 plugs (NEW plugs). I am having them ship a new magnetic pick up sensor and will swap that out as well.
I have read about guys running NGK iridium auto plugs, do you guys recommend those? Any other recommendations?
Any help would be greatly appreciated. When the system works, it works GREAT!
Dan
Hello VAF!
First the disclaimers: 1) I have searched and read everything regarding the Jeff Rose/EA ignition system here. 2) I am new to electronic ignitions and relatively new airplane. (To me at least)
Background: I purchased the plane in August of this year, 1999 Aerosport O-360-A1A, 537 TTSN. Left side Slick magneto recently overhauled 30 hours ago. Right side is old school (Gold panel with coils and DIU combined) Jeff Rose electronic ignition.
Problem: About 4 weeks ago, I started noticing an increase RPM drop during my magneto checks. Before the checks would be 0-10 rpm drop when running on EI only and 70-100rpm drop when running on Slick Mag only. My RPM drop quickly became 150-300rpm drop when running EI only. After cycling the power (10amp breaker switch) the ignition would 'turn on' and the engine would gain 150rpm and 'smooth out'. Another EI only check would show normal 0-10rpm drop.
Phone con w/ ElectroAir: After describing the problem with ElectroAir, they said it was a faulty switch, so I ordered a new one and put it in. (I had a local electronics store test old switch and it worked fine). New switch did not fix the problem. I called ElectroAir again and they were convinced it was a problem with the circuit board (as documented in forums here).
Problem 2: The problem gradually got worse over 3-4 flights. The EI would not 'turn on' until cycling power or running engine on Slick mag. (I can't say which it was, the cycling power or running of engine, cause neither was definitive or able to single out in testing.) I checked the timing of the EI and it was spot on. So I pulled the unit and sent it back to ElectroAir for diagnostics. I got a call this morning and the unit is running 'great' they said. They left it outside in cold Michigan weather for 2 hours and tried it again and it worked 'great'. So now where am I?
Possible solution?: I have checked the magnetic pick up sensor with my ohm meter and it passed the 600-800ohm test with 656ohms. I also did the voltage test on the sensor and it worked fine also. The Magnetic pick up sensor is the old size 3/8".
My thought is that the Magnetic pick up sensor has a short and when shorted out on the start, the sensor does not sense any RPM and thus the unit does not fire. After the vibration from the engine being run on the single mag, the sensor short is connected and picks of RPM and the unit fires. I know the sensors are prone to failure, but.... any ideas? What else could it be? What else should I look for.
In the mean time while I wait for the unit to come back from ElectroAir, I am going to change the spark plug wires. I have the Taylor 8mm wires running parallel to Autolite 386 plugs (NEW plugs). I am having them ship a new magnetic pick up sensor and will swap that out as well.
I have read about guys running NGK iridium auto plugs, do you guys recommend those? Any other recommendations?
Any help would be greatly appreciated. When the system works, it works GREAT!
Dan
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