ZDZ 80RV ?Ignition problem
 

Hi Mike
I have a ZDZ 80RV (from RC Showcase) which i think has an ignition problem. it is still on run in fuel (32:1, 95 octane) and is about 5 hours/8 months old. It has run well, until until it died very suddenly on 3/4 throttle at the start of an immelman last weekend. 2 prior flights the day before had some intermittent rough running a few times at half throttle.

tested spark - obtained 2 or 3 sparks consecutively, then none for many rotations, then 1 or 2 and then none and so on. (spark plug removed from cylinder head and prop turned by hand at this point.)

Ign. battery and switch cheked out OK (5.2 volt (NiMH 4 cell Sanyo 2300mAH) present at the plug where ign plugs into. Ign battery still had 1700mAH left in it when tested at 0.5amp discharge later on.) I had noticed that ign battery was using about 250 mAH per flight for the last week which i thought was rather high current usage, but i had only just started monitoring this so i didn't have a baseline. Battery voltage dropped to 4.85 v under 0.8A load (acceptable load test).

when i test the spark now, (by rocking the prop to & fro past the hall sensor with spark plug out of head) i get a spark every time. same if i do it with a new plug. this makes me think the plug and lead is OK, and perhaps the ignition "heated up" and failed in flight, but is OK now after a day to "cool off". is that possible?

could the spark be too "weak" as it won't even fire/start at present. what do you think?

ADDITIONAL INFO: a friend has a brand new ign for ZDZ 40-50 size engine. can i run/try this ignition module in the 80?

RE: ZDZ 80RV ?Ignition problem
 

The ignition typically will draw approx 600-800ma at full throttle. It sounds like nothing more than a weak battery.
Let me know.
Thanks,

RE: ZDZ 80RV ?Ignition problem
 

Ok I'll try a new battery and let you know how it goes. (my discharge curve shows that my current Ign. battery falls below 4.8 volts after only 350 mAH are drawn from it then sits around 4.5-4.7 volts; nothing wrong with the battery, just not a good choice for this application i guess.)

my ignition is a ZDZ serial no. 3678; it says input voltage 4.8 - 9.0 volts on the case. can i use a 5 cell NiCd/NiMH without regulator, or even a 2 cell LiPO without regulator?

RE: ZDZ 80RV ?Ignition problem
 

new battery (5 cell 2300mAH sanyo sub c) no better. tried friends brand new (40-50 size) zdz ignition on my existing battery/switch setup. getting 7-8mm spark in spark plug cap. my ignition can only manage a pittly little 1-2mm spark, so i figure it's not well. could be fault in high tension lead, am sending it in for you to test.

RE: ZDZ 80RV ?Ignition problem
 

faulty ignition unit has been replaced, new one installed and zdz 80 running nicely again! thanks RCU staff for efficient, prompt service!

RE: ZDZ 80RV ?Ignition problem
 

Mike
I left a voicemail and sent for a return authorization. My igition unit for my new Super 80 I cannot get to work. I even hooked up several good packs directly and rotated the crank by the sensor with the spark plug in and out of the motor attched to the plug holder.

Im out of ideas? any ideas. I think its bad The motor was bought from troybuilt, but I understand we go to you for service.

I left my cell ph on the email and voicemail

Thanks for the prompt service thus far.

Dave

RE: ZDZ 80RV ?Ignition problem
 

I have an 80 rv blue, had the same engine died in flight issue, could not get the engine to fire up again, would not even make the engine pop, got spark with the plug out, but engine would not fire. sent the ignition in and it was replaced, fired right up as before. I suspect that the electronic advance went south and was causeing the plug to fire at the maximum advance even though the engine was not running. if I were you I'd send your ignition in before I spent too much time troubleshooting beyond what you have already done.

RE: ZDZ 80RV ?Ignition problem
 

thx
will do
goose