Eliminating Bendix D2000/3000 Magnetos

[walkman]

Originally Posted by mgon

Walkman

Just completed same, EIGH 1 from Protek
and single mag.
0320-H2AD
I'm getting a drop of about 250 rpm
from both to EI only
No miss, idles 750 rpm w/ both
will only idle 400 rpm w/ EI only.
Check all connections.
What is yor Mag Drop

MG

on my flight back from cincinnati yesterday I stopped at 0I8 Cynthiana KY for $5.20 avgas. I noticed a strange drop out. While idling on the ramp, heads down on the gps, all of a sudden my RPMs dropped several hundred, stayed there long enough for me to notice, then came back up. I was unable to reproduce. flight back was all normal and fine.

I rechecked my mag timing this evening, it was set around 27 BTDC. either it changed with breaking the mag in or I was sloppy. No idea if this has anything to do with anything but.....will collect more data.

[walkman]

Originally Posted by airtractor8

I am contemplating doing the single mag and EI conversion on my H2AD as well and would appreciate some details of your experience doing the conversion .
Can you give some details of the single mag p/n you used for the conversion. The bendix single mag needs to have right hand rotation to suit the H2AD. Did you find a suitable mag ( they all seem to be left rotation) or did you have a mag shop convert one to right hand rotation? Did you use the original mag drive gear/coupling setup or something modified? Are you using an impulse coupling on the mag to start the engine or are you starting on the EI?
Thanks in advance for any help
Regards
Graham
RV6-H2AD

Graham

Check the document I linked to in my original post. that should get you started. I think you should be able to find the same mag without the "L" in it. Call Aaron at Select Aircraft in Lancaster TX and tell him I sent you.

[mgon]

I'm refering to the drop when switching to EI only.
This is where I see a 250 rpm drop.
I was wondering what you get.
MG

[mannanj]

Originally Posted by walkman

on my flight back from cincinnati yesterday I stopped at 0I8 Cynthiana KY for $5.20 avgas. I noticed a strange drop out. While idling on the ramp, heads down on the gps, all of a sudden my RPMs dropped several hundred, stayed there long enough for me to notice, then came back up. I was unable to reproduce. flight back was all normal and fine.

I rechecked my mag timing this evening, it was set around 27 BTDC. either it changed with breaking the mag in or I was sloppy. No idea if this has anything to do with anything but.....will collect more data.

Hope you find something quick! Could it have been a slug of water? Still installing mine so I'm keenly interested!!!!

[rcpaisley]

Hi Mannan,
I weighed some batteries laying around the shop today.
A Concord aircraft battery (RV sized) is 22lbs. Two of the Odyssey PC625s total 26 lbs. Most of our installations end being a swap from one Concord to two of the PC625s.

There is a loss in weight when removing two mags in favor of our dual ignition electronic setup.

The overall system swap out for a dual ignition when the battery situation is as described above ends up at close to the same weight when all is said and done for most installations.

Robert

[walkman]

Originally Posted by mgon

I'm refering to the drop when switching to EI only.
This is where I see a 250 rpm drop.
I was wondering what you get.
MG

I checked it last night. By feel only, no tach when on ei, it can't be dropping more than 100-150 going from both to ei only. That is from 1,800.

[mgon]

I checked with Robert, I was checking at to low an RPM (1500rpm)
@ 1800rpm I'm getting about the same as you.
MG

[walkman]

Originally Posted by walkman

on my flight back from cincinnati yesterday I stopped at 0I8 Cynthiana KY for $5.20 avgas. I noticed a strange drop out. While idling on the ramp, heads down on the gps, all of a sudden my RPMs dropped several hundred, stayed there long enough for me to notice, then came back up. I was unable to reproduce. flight back was all normal and fine.

I rechecked my mag timing this evening, it was set around 27 BTDC. either it changed with breaking the mag in or I was sloppy. No idea if this has anything to do with anything but.....will collect more data.

Well I experienced some momentary drop outs this evening taxiing back to the hangar. Momentary meaning 1-3 seconds of suddenly dropping rpm, stumbling a bit, then coming back up. This was not noticeable on the taxi out or in flight. I turned off the ei and the behavior was unchanged, that is still had a drop out every now and again.

I will start by checking p lead connections.

[mannanj]

Originally Posted by walkman

Well I experienced some momentary drop outs this evening taxiing back to the hangar. Momentary meaning 1-3 seconds of suddenly dropping rpm, stumbling a bit, then coming back up. This was not noticeable on the taxi out or in flight. I turned off the ei and the behavior was unchanged, that is still had a drop out every now and again.

I will start by checking p lead connections.

Have you found the problem?

I finally got my Dual Electronic EFII System installed and running. (My hangar neighbors were starting to accuse me of making a career out of it!) Short test flight Fri. went well. No numbers though. The engine idles much smoother now. 550rpm and she's ticking over like a Swiss watch.

Today's flight was great. At 8500 ft., WOT about 22.3 in., 2300 rpm, I could get at least .4 gal. per hour less fuel flow before engine started to miss than I could with the mags. I could detect no dicernable difference in rpm switching from either both/left/right and between the main buss and the emergency back up battery either at runup rpm's or cruise rpm's.

I'm not big on numbers and keeping accurate records, so I won't have very quantitative figures to share but saving over two dollars per hour on fuel seems ok to me.

I'll try to get more figures later this week.

[walkman]

I was glad to hear you were done and working well.

I'm half inclined to leave my mag off until its time to run up and the depart just for that low speed idle improvement.

I did have a question about the block off for the drive gear. Other than the mag drive gear itself, is there anything else to remove? Like a pilot bearing etc? If so, how did you remove it? How did the block off work for you?

I'm beginning to think my issue was/is "morning sickness".