Need Help! Electro Air / Jeff Rose Ign

Omega232Devils · #1 12-23-2011, 12:25 PM

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

rocketbob · #2 12-23-2011, 12:39 PM

Quote:

Originally Posted by Omega232Devils

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.
Dan

The VR sensor (magnetic pickup) is intermittently bad or the gap between the wheel and the sensor is too large. I definitely think that is your problem based on my past experiences with Electroair, which has generally been very good.

Personally I like NGK BR9ES plugs. Cheap and work well. Autolite 386s burn up too quickly.

RONSIM · #3 12-23-2011, 12:47 PM

with the -8A I fly (O320H2AD). Older Electroair system (all-in-one) coil pack and controller --- it just quit working ---- Electroair said sounds like the pickup, so I pulled prop and installed new sensor. No joy! Sent the coil pack back to Electroair for diagnostics --- turned out to be the problem. This necessitated replacing the entire system with the new (separate) components. The system works fine, and the support Electorair gave me as I fumbled through the install was good.

By the way, the first (new) sensor I installed failed because I did not bend the wire coming out of the sensor far enough and the back of the flywheel cut into the wire -----

Ron

Omega232Devils · #4 12-23-2011, 01:32 PM

Bob, thanks for replying. I was hoping you would after seeing your name pop up on this subject many times. I will replace the sensor and inspect the MTH while I have it off. Other than this I am lost with what to check! Can you elaborate on checking the gap? Are you still running Taylor 8mm wires in parallel?

Ron, I am not sure what you mean by sensor behind prop, I was under the impression those were only installed on 6 cylinders. The only sensor I have is the magnetic sensor in the MTH. Can you clarify?

Dan

rocketbob · #5 12-23-2011, 01:58 PM

The gap between the sensor tip and the 60 tooth wheel should be 0.015". You have to pop the cover off when replacing the sensor and stick a feeler gauge in there when replacing the VR sensor.

Tom Martin · #6 12-23-2011, 02:05 PM

Another thing to check is the actual sensor mount. I replaced the aluminium mount with a steel mount as vibration would cause a problem. Make sure the mount is tight. A rather large gob of RTV between the mount and the engine case will also help to stop vibration.

Omega232Devils · #7 12-23-2011, 02:14 PM

Bob, thanks I will check the gap today as I am removing the MTH to inspect.

Tom, I am confused by your post, the bracket you are describing sounds like the one mentioned by Ron around the prop. I thought this was only for 6 cylinder installs. I don't believe I have one, will double check today. I don't have any wires running from that area to EI unit.

Again thanks everyone. I am racking my brain.

Dan

Stu McCurdy · #8 12-23-2011, 02:40 PM

I had the same setup, Slick mag left side, Gold Board ElectroAir right side with a sensor pickup in the right mag hole. My system was 10 years old and running fine. One day I started getting some "missing" in flight, that turned to a dead electronic ignition. Landed, called ElectroAir, they shipped me a new pickup with a better, stiffer, more vibration resistant connector wire to the Gold Board. I also changed the Plug wires. That fixed the problem, no more "missing", but occasionally I would get a reduction in Advance on the Advance Meter which would be accompanied by a reduction in CHT, then it would go back to normal. ElectroAir suggested it was probably the old style Gold Board since it sits inside the engine compartment and the potting is subject to deterioration over time. They shipped me a new digital system which has the Ignition Towers and Manifold Sensor in the engine compartment but the Control Box is mounted aft of the Firewall. Had to cut a new hole in Firewall for the bundle of connecting wires. I installed it and now have a smooth running engine with no change in Advance Meter or CHT. Back to like it was new 10 years ago. I use the 386 plugs and toss them every year, $7.50!!

Omega232Devils · #9 12-23-2011, 02:52 PM

Talking with ElectroAir I thought I was going to have to upgrade. (Still might have to) was the new system coil pack the same size as the older coil +DIU the combo? If not what did you do to mount the new coil board to firewall?

Stu McCurdy · #10 12-23-2011, 03:59 PM

Quote:

Originally Posted by Omega232Devils

Talking with ElectroAir I thought I was going to have to upgrade. (Still might have to) was the new system coil pack the same size as the older coil +DIU the combo? If not what did you do to mount the new coil board to firewall?

I had my Gold Board mounted on the right side of the engine mount on an 1/8 inch aluminum platform which is mounted to the engine mount in the vertical with adel clamps. The new Double Coil Towers themselves are the same size as the old ones on the Gold Board but the Manifold Press Sensor is separate and bigger than the old one, therefore the platform the towers sit on is shorter but the same width. I was able to use two of the existing holes to mount the Tower platform but had to drill two new ones. I was able to also mount the larger Manifold Pressure Sensor in same location as before. On my RV-8 I mounted the new Control Box in the forward baggage compartment on the aft side of the firewall just inside the door, below the horizontal former.