It's time for the CI on one of my Rotax 912s. I have read every post in this thread and I want to thank everyone for their fantastic contributions. It appears that MS did what Jim (Piper J-3) suggested --- removed material from the top of the float to reduce the weight. I sincerely hope this long sad saga is over! I ordered two pair of MS80-430's today
I have two Rotax 912 ELSA powered airplanes. One with 277 hrs (2006) and one with 102 hrs (2005). Both were run exclusively on 91 Non-Oxygenated Mogas in Minnesota. The floats still meet specs, BUT as pointed out in this forum, one month after weighing them, they may sink.
As of October 2019, I have switched to 94UL Avgas (Swift Fuel) which is identical to 100LL without the lead. Unfortunately this fuel is not widely available, but hopefully that will change.
BTW Jim, I learned to fly in a 1946 J3 C65 - N6848H. Your J-3 (N6841H) and mine must have been on the mfg floor at the same time in 1946