Rotax 912 Breakdown !!

[RossM]

http://www.vansairforce.com/communit...?t-64964.htmlI no nothing of motors, whether this is of interest to you!

[blakemorem]

Thanks for that Ross some good hints there, Like descent battery,good battery,leads, and good connections and it also appears the later version CDI"s have +3 Deg ATDC protection against Kick back built in to the timing. It probably pays to ask Bert Flood about this if ever purchasing a new CDI unit. Or ask Birdy how much he wants for his ;D ;D ;DMike.

[Brian]

Thanks for that Ross some good hints there, Like descent battery,good battery,leads, and good connections and it also appears the later version CDI"s have +3 Deg ATDC protection against Kick back built in to the timing. It probably pays to ask Bert Flood about this if ever purchasing a new CDI unit. Or ask Birdy how much he wants for his ;D ;D ;DMike.The new CDI units have the soft start in them, no need to ask. Guess that makes the $800 better value.My " BUSH" button is a new invention Graeme, should be able to be released to the general public in a couple of years

[blakemorem]

Sounds like the 07 CDI"s had the poor quality caps in them.Mike.

[Kyle Communications]

Hi AllI was directed to this thread regarding the Rotax ECU/CDI units whatever one wants to call them...Ignition Modules iare probably more appropriate. I am chasing a blown up soft start one. I can get them apart it is a long process but very successful so far. I want to make a version that can do all rotax engines also have some plug in diagnostics as well. I have the older non soft start units apart and drawn out the circuit and its pretty basic. From the testing I have done the large capacitor does not seem to be the issue at this stage the mosfet seems to go when the unit appears dead. The capacitor loses its value over time and heat and I think that when the capacitance drops a little the modules become cantankerous. It seems the old 4 wire and the six wire units are done by Ducati I believe the later soft start unit may be made by Motorini. maybe this is why there are far less failures. We would like to make a version that we can plug a diagnostic into to be able to check voltages and capacitance and a few other measurements this way we can tell what is actually going on inside the unit. We don"t want to reinvent the wheel here but a bit of forward thinking and application can produce something hat will be extremely cheap if you ever need a replacement.So I am on the bight for any blown up soft start versions off 912uLS engines. Anyone who can help with a donation of their blown up unit will receive

[MadMuz]

I know that the guts of them is set in resin, like I said, you can mill the resin a mm at a time to identify the components, but for every substance (resin/glue) there is something to dissolve it. Ask glue/resin manufacturers what can soften or break down resins? Surley if one soaks an open black box in the appropriate chemical, the resin will liquefy? Drip various common things on insignificant pieces of resin and see if it softens? Things like glue and lable remover/unstucker, petrol, acetone, battery acid etc.... just do it outside, wearing protective clothing and specs, in case it reacts worse than you think... and don"t breathe any fumes off it. Maybe subject the resin to heat? Soldering iron? small burner flame? Oven? see if the resin will become soft or liquid (whilst hot) so you can see the circuit board and components in situ? Everything man makes can be defeated

[Kyle Communications]

I have already got it sorted to get the units apart...just need a later version of the soft start to look at

[Adrian S]

Hi Mark,Give me a call on 0427094552 I should be able to help with a CDI module.Cheers,Adrian S ;D ;D ;D ;D

[blakemorem]

Hey Mark i"ve been told never run the CDI without the spark plugs earthed as the back EMF will kill the mosfets it may save you some grief. It would also be interesting what tolerance and temp rating is on the original caps and resistors for that matter, Good to see you are making the quality audit by design the manufactures may have to improve their quality or rethink their price.Mike.

[WEST OZ FLYER]

Yeah Mike that was the main context of the Sport Pilot article in regards to the ignition box failures. The key especially, as you can"t earth the magneto"s while cranking like you can with switches. However after looking for other stuff for my 912 I came across this. http://www.lockwood.aero/p-3710-adva...odule-kit.aspx Seems like a cheaper option. Sorry Chopper a bit late now.

[Brian]

Yeah Mike that was the main context of the Sport Pilot article in regards to the ignition box failures. The key especially, as you can"t earth the magneto"s while cranking like you can with switches. However after looking for other stuff for my 912 I came across this. http://www.lockwood.aero/p-3710-adva...odule-kit.aspx Seems like a cheaper option. Sorry Chopper a bit late now. Its okay, I will only cry for a while & then I will be fine !

[blakemorem]

Just one thing I"m curious about. Whats the warranty agreement with rotax if you are using different brand CDI unit. Mike.

[birdy]

Agreement?Dout theyd agree with that.

[blakemorem]

Or anything in general for that matter Birdy. Sometimes i look at the paperwork on the engine and wonder.

[MadMuz]

Whats the warranty agreement with rotax if you are using different brand CDI unit. Mike.You get the full 12-20 warranty.....12 feet or 20 seconds