Page 2 of 6

PostPosted: Tue Dec 11, 2007 12:37 am
by Chappy
I've been using these and similar retrofit modules for at least 25 years. I've even moved them from one worn out engine to a newer one. Out of probably a dozen or more modules, none have failed. I had also planned on trying these modules on my Rotax engines.

Don's installation looks very nice and neat. However, because of a concern for heat affecting the modules, I planned on mounting mine externally. I've always mounted the modules externally and as far from heat sources as possible.

Now, if external heat from the engine impinging on the module was the only heat source, I would feel pretty good about predicting that they would hold up if mounted externally. Unfortunately, there's a second heat source at play that, in this installation, might very well cause modules to fail prematurely. Most of the installations I've made were on small engines that never ran much over 3600 rpm, and were 4 stroke types with a spark every rotation (so called wasted spark type), so the module is called upon to switch the load that fires the spark plug 3600 times per minute at full trottle load.

Now, on the 2 stroke Rotax operating at close to 6000 rpm, and again firing the spark plug every revolution, the module will be seeing almost twice the duty cycle of the units I've installed, and that may generate enough additional internal heat to destroy the module.

Perhaps, if there turns out to actually be a reliability issue using these modules, installing the modules so that they only have to disperse internally generated heat in a cooled environment would mitigate the problem. Personally, I had planned on mounting the module external to the engine. I also considered mounting it where it would be in some prop blast, mounted to an aluminum, finned heat sink using thermal heat sink compound, and thermally isolate the assembly from the engine - just to be on the safe side (the old belt and suspenders philosophy). If you are using these modules in Canada they may never give a problem, but here in the mid-Atlantic region of the States, 100+ weather has to be taken into consideration.

Chappy

PostPosted: Fri Apr 25, 2008 12:23 pm
by huronflyer
So did these modules ever pan out - like last on 185s???
Or do we still need to use the Ducati ones...
Daver

PostPosted: Sun Dec 28, 2008 11:36 am
by gdewsbury
Chappy

I have been reading some of the patent articles for the computer ignition modules. By mounting the unit completely isolated from the engine, you may be negating part of the circuit used for hot engine starts. Some of these units have a temperature sensitive resister that advances the timing for hot engine start.

Glen

PostPosted: Sun Dec 28, 2008 11:34 pm
by Chappy
Glen,

Thanks for the info. That's interesting and good to know. I wasn't aware of that "feature". So, externally mounted but still thermally coupled to the engine case might be best for reliability and hot starting.

Chappy

PostPosted: Mon Dec 29, 2008 2:51 pm
by Don
Hi Guys,
I don't have much to report about my use of these modules yet. I have ran a little over 2 tanks of fuel through the engines during the summer with the longest single run time of about an hour. They were flown for about 20minutes the rest is taxi time. I did run, shut down and restart the engines several times during this period and they started very easily. This summer barring any surprize health or family problems I should be able to provide some good info for everone.

Happy Holiday's To Everyone!!!!

Don

PostPosted: Mon Dec 29, 2008 9:56 pm
by huronflyer
As you probably already know...
Brian Buckley has been running the modules in parallel with the points; he can flip a switch and run on either.
They start fantastic even when damp.
One caveat they can be switched in flight, but best ONLY if they are running, since they could fire up backwards if not already in motion.
Cheers.
Dave H.
CYEL
C-IIII

PostPosted: Wed Feb 11, 2009 12:02 pm
by 89 CHARLIE
Can anyone tell me if the Nova II ignition works on the Rotax 185? I see discussion about setting the timing but what i have read about the Nova II it has no timing adjustment. It uses the coil to determine when to fire the spark. I would appreciate any info anyone can provide.

PostPosted: Mon Feb 16, 2009 11:09 pm
by JPXman
yes the nova modules use the relative position of the coil to the magnets on the flywheel - and the flywheel position is directly proportional to the piston position to TDC. so if you move the coil itself (or rotate the stator plate it is mounted to) then you have some level of timing control.

with these modules, you need to mark the original timing on your good-running 185 with points ignition. scribe a mark on the case, and on the spinner (or back end of the engine, but if you use the flywheel for a mark, you have to mark it relative to the crank - tricky). use a timing light and graduated markings.

then remove points (or as brian B did, leave them in) and mount nova module to the wiring. if you can get the engine to run, use the timing light to see how far off you are, then then just move the coil by adjusting the stator plate the same number of degrees.

very basic description, but that is how far i got with the nova module before I started tinkering with wildfire CDI modules and such. one lazairhead named tom T used the nova I module and had to machine the slots a bit wider to get the proper amount of adjustment - actually i think he made a subplate on which to mount the stock stator plate.

Tyler

PostPosted: Tue Feb 17, 2009 1:36 am
by peter
Hi Guys.....for what it's worth, I've just installed electronic modules a la Brian Buckley on my 185's....these modules are the blue atom kind and are simple in the sense that no timing adjustment is necessary.....All I can say is I'm totally impressed.....they start with no tendancy to kick back and idle noticably smoother....The spark with the plug laying on the head looks almost twice as hot....didn't notice any increase in rpm on the T.Tacks though....5550 and 6000 with bi props.......I mounted them inside the motor mount block with the three way switch outside and reachable, and they switch back and forth with no hesitation or apparent change in rpm....The big question of course is, how reliable are they going to be?.....well the sweet thing is having the points just a switch away for back up, or visa versa.....either way it's a win win situation, if nothing more than for easier starting....To find out more about these blue atom computer ignitions, google in bantasaw.com ......Man,I hope they prove out.
Now that I've got the plane ready to go, and the snow has melted enough to get the plane out of the barn and trailered out to my strip, there is not enough snow for skis, and the field is too frost bumpy for wheels....I'm hoping for 4or5in of new snow so I can try the skis...I'm not like Shorty who flys on frost..ha ha or 2ft deep for that matter.
Ski flying is new to me and I would appreciate any tips....what to look out for etc..................Thanks all...........Pete ser. 3 iggi

PostPosted: Tue Feb 17, 2009 12:02 pm
by lazairiii
Hello Peter,

I hope for the sake of all of us, you took some pictures of the installation of these units. I'm curious how this unit installs with the points intact, and how they switch back and forth.

I went to their website and it doesn't look like there's much to installing these units really. I'd seriously have to test these units out however to feel confident that they would perform smoothly and have durability and longivity.

Any pics?

George