We had an identical issue at our field earlier last year and it turned out to be a faulty ignition battery pack. You may want to check the pack to make sure the output is correct.

Points well taken. I'm all for trying the easy things first!
McD

Hello guys and gals I was wodering and I know thing gets me in trouble when I do it. But how many of you rap you igintion in foam or something? Or can you just go with some good velcro and a couple of zip ties to make sure it does not rattle?? Thanks

Originally Posted by kingsflyer

Thanks for the hints. It's a real PITA to get that cowl off, and the OPTO is buried in the fuselage, so I have my work cut out for me. First I plan to reset the plug to .018". While it's out I'll check the timing and verify 28 degrees BTDC. After a test run, if the miss is still there, the OPTO will get bypassed and, as a last resort, the ignition module will get pulled. I'll let you know what I find.
McD

My Moki 60 (2x30cc) runs full power with 18° advance. In small 20cc engines, 28° may be way too much.

Originally Posted by giddyuperic

Hello guys and gals I was wodering and I know thing gets me in trouble when I do it. But how many of you rap you igintion in foam or something? Or can you just go with some good velcro and a couple of zip ties to make sure it does not rattle?? Thanks

I put a piece of foam between the aircraft and ignition then zip tie it down snug. The foam of course will absorb most of the vibration generated by the engine. I am pretty sure most of the guys I fly with at the field do it the same way.

Originally Posted by pe reivers

My Moki 60 (2x30cc) runs full power with 18° advance. In small 20cc engines, 28° may be way too much.

I agree that 28 degrees sounds pretty high, but here is a quote from the DLE20 manual:

Ignition Timing Adjustment

The ignition timing is preset on the DLE-20 at 38-40° before Top Dead
Center (TDC). The ignition timing can be advanced or retarded by
loosening the (2) ignition sensor Phillips head screws and sliding
the sensor to the full extent clockwise (41° advancing the ignition)
or counter clockwise (37° retarding the ignition). Be sure to retighten
the Phillips head screws after adjusting the ignition timing. It is
best to attach the sensor with the screws centered in the slot as a

starting point.

I moved the sensor as far as I could to retard the spark, replaced the plug with a properly gapped new NGK CM-6, and checked the high tension lead. I'm ready to start testing tomorrow afternoon and see if these initial changes have had any difference.

McD

On small engines, a ignition timing of 15° to 22° will be plenty!!!!!

Originally Posted by pe reivers

On small engines, a ignition timing of 15° to 22° will be plenty!!!!!

I agree, but I would have to drill and tap the front of the crankcase and remount the pickup to reduce the timing that far. I'm not sure but have you measured the amount of "electronic" advance the DLE ignition module gives under higher RPM? Since they are running so much mechanical advance, they may not need, or program in, as much electronic advance.

http://www3.towerhobbies.com/cgi-bin...?&I=LXANVN&P=Z

Ran my engine yesterday and still have the miss. I guess the plug, timing, pickup lead, and high-tension lead were not the problem. I'll disassemble the fuselage today and dig out the battery, opto module, and switch wiring so I can bypass each one and see if I can find the faulty unit. Last resort will be to replace the whole ignition module with one from my DLE 30 that I have on hand.

McD

Originally Posted by kingsflyer

I agree that 28 degrees sounds pretty high, but here is a quote from the DLE20 manual:

Ignition Timing Adjustment

The ignition timing is preset on the DLE-20 at 38-40° before Top Dead
Center (TDC)....................

I moved the sensor as far as I could to retard the spark, replaced the plug with a properly gapped new NGK CM-6, and checked the high tension lead. I'm ready to start testing tomorrow afternoon and see if these initial changes have had any difference.

McD

That particular timing quote is NOT from the official DLEngines, but rather is from the Tower Hobbies/Hobbico DLE 20 Owners Manual, and is flat out WRONG!!!

This is the official web site of DLEngines;
http://www.dlpower.net/

Your quote came from the non-official DLE web info site which is in reality the
Hobbico/Tower Hobbies site;
http://www.dle-engines.com/index.html

Their manual, while a lot more extensive, has it's errors too;
Page 3 - Lawn Boy Ashless......very poor choice, far better choices exist.
Page 7 - Dubro Vibration reducing eng mount....truly unnecessary for this DLE20.
Page 9 - ..."deactivate the throttle return spring"....a personal choice, but that little spring puts
very little pressure on a servo. Far better to leave it on there, as it will return your throttle to
idle should your throttle linkage ever come off. The idle SCREW should be removed, as you do better controlling your idle from your transmitter, and with that screw out, you can more easily kill the engine if you need to.
Page 13 - Ignition timing 38-40BTDC....waaaay wrong! 28 is correct.

Those are the errors some of us have found

Even though you may have purchased your DLE from your LHS -or- TH directly, don't feel too bad about not knowing the above things. They try fooling many, and now you know.

Set your timing as close as possible to 28 degrees, and gap your new NGK/CM-6 plug to .020 and go fly!!!

Good news, Bad news.

Good news is that I found the problem. Bad news is that the ignition module was the culprit. I replaced the module with one from my DLE 30 and the little 20 purrs like a kitten - not a miss to be heard.

DLE20 Fixed (4 min 7 sec)

Thanks for all the help and suggestions. This tread is wonderful for us newbies.

McD

Doing some Maintenance on my DLE 111 this is what the plugs look like dark one is from right cylinder as you are looking at it from the front. What do you guys think

Thanks

Adam

Kinda looks like the dark plug is fouled out. Could be running to rich or you might have bad ring in that cyl. I woul replace both and check again after a couple flights. Steve Mullis

Off your topic sorry. But can you guys tell me if it is okay to use a 6volt nimh pack on the DLE 30? Every buddy says no but the manual says Technical Data:
Ignition Battery: 4.8-6.0V NiCd or NiMH, 6.6V LiFe or 7.4V LiPo pack (LiPo or LiFe use requires voltage regulator.)
Compression Ratio: 7.6:1
Gas/Oil Mix: 30:1
Replacement Spark Plug: NGK CM6 (DLEG5510) or equivalent
Weight Breakdown: Engine: 32.1 oz (910 g); Muffler: 2.1 oz (60 g); Ignition: 4.2 oz (120g) I don't want to let the smoke out of the box I have the 4.8 on it right now and I am having starting problems??? Thank you and sorry to take you off topic.

A freshly charged 4-cell NiMh battery pack will have 6.0 volts at the battery terminals. A freshly charged 5-cell NiMh battery pack will have 7.2 volts at the battery terminals.
I fly my DLEs with a 4-cell pack and don't have any problems.
McD

Thanks do you think it makes a bater spark with a higher voltage pack? Does the 4.8 have a weaker spark then the 6volt pack or does it not matter as long as the spark plug get the 4volt min? Thank you very much,