Big-time Mag Drop

Rotax Wizard, thank you for the directions.  I don't know, however, where you got the idea the unit is question was "used."  It was, indeed, sold to me as new by USA supplier.  This was after some weeks of waiting for the supplier to receive shipment from Rotax.  Is the 2025 designation the source for your supposition?  In any case, I will advise the Forum of the results of my inquiry.  Again, I appreciate your valuable information.

HKK, the ignition drop anomaly occurred after a couple of hours of normal operation following plug change.  All plug caps are secure.  The RPM drop was significant and in no way resembled a single or even double fouled-plug scenario.  Trust me, I respected Occam's Razor by exploring all the simpler solutions in my trouble-shooting.   I appreciate your suggestion.     Jim

Hi Jim,

my message was: maybe 1 Spark is missing - no more. This can occur every time even the engine runs good before. To secure a cap is good but indicates not a spark. Contac failtue at the cable, the cap or Spark Plug, mayby at the coils or ignition modules.... Do you checked/really see a spark at all sparkplugs - this was my sinple hint. If no, to find the reason cames later. I think you checked it because you respected the Occam's Razor.

Greetings

HKK wrote:

Hi Jim,

my message was: maybe 1 Spark is missing - no more. This can occur every time even the engine runs good before. To secure a cap is good but indicates not a spark. Contac failtue at the cable, the cap or Spark Plug, mayby at the coils or ignition modules.... Do you checked/really see a spark at all sparkplugs - this was my sinple hint. If no, to find the reason cames later. I think you checked it because you respected the Occam's Razor.

Greetings

Hi HKK,

A mag drop of 3000 isn't just 1-2 plugs.

hi Jim   

you said in the original post ..

"Recently replaced ignition unit with new.  Other one has 100 hrs on it. "

I took that as the replacement had 100 hours on it, hence used.  Sorry for my misunderstanding. 

Cheers

Have been in contact with USA supplier and he instructed me to the site Rotax Wizard schooled me on.  As we are in warranty, he is optimistic that Rotax will OK replacement module.  He is sending replacement to me at this time and will reimburse my cost when Rotax greenlights it.  I will advise this Forum of further developments.  I appreciate all comments you folks have provided.    Jim