Use of 100 LL with 912 ULS

I haven't had to use any 100 LL in my Kitfox with 912 ULS yet. I know it's used by many owners, but I've been lucky to have access to a supplier of non-ethanol 91 octane mogas for about $3/gal. I built a 40 gal. tank w/ pump, etc. for the bed of my pickup & it works great, but I realize I'll have to use 100 LL frequently on long cross country trips. My question is, do those of you using it regularly open and clean the oil tank at every oil change? It seems like that would be a real pain. I plan on using Decalin when burning avgas. Is TCP considered any better by anyone on this forum?

Thanks in advance.

I use Shell 91 with 10% ethanol about 90% of the time in my RV-12/912ULS -- seems to work great over the past 750+ hours. When forced to use 100LL on trips, I add Decalin. I rarely have to clean my oil tank due to my high use of unleaded mogas. Cleaning the oil tank once a year for 100LL users is relatively simple and does not generally require purging of the oli system if done properly. ROTAX OWNERS site discusses this aspect of oil tank cleaning versus purging.

Thanks, Steve & David... I appreciate it!

I use clear 92 Mogas 95% of the time, but I still clean my oil tank at every 50 hour oil change. Rather than drain it thru the plug on the bottom (and then have to replace the safety wire) I just remove the two fittings on the tank lid and empty the tank with a suction gun, and then inspect and clean the internal parts. I never remove the tank from its mounting bracket. I tie up the outlet hose so it remains full and no purge is ever needed. The tank inlet hose from the bottom of the engine can be left dangling down to completely drain the oil from the crankcase. Its actually surprising the grey lead slime coating the inside of the tank after a long x-country trip burning 100LL.

Thanks, Jim!

Hey John,

Where are you buying your autogas? Sam Hill, or do you have another source? I’d prefer not to be running ethanol, but other than Brighton, I’ve only been able to get 87oct autogas.



Thanks!

Hey John,
I, unfortunately, burn 100% avgas. Change the oil every 25, filter every 50 and clean the tank every 100 or at annual whichever happens first (which has been about 50 hrs for the last several years). I also find cleaning the tank a pain but if you are burning mostly mogas then I would think cleaning at annual should be more than fine.

Yep, it’s Sam Hill.

Quote:

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Originally Posted by Dorsal

Hey John,
I, unfortunately, burn 100% avgas. Change the oil every 25, filter every 50 and clean the tank every 100 or at annual whichever happens first (which has been about 50 hrs for the last several years). I also find cleaning the tank a pain but if you are burning mostly mogas then I would think cleaning at annual should be more than fine.

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Thanks, Dorsal. I sure wish Swift Fuel or some other lead-free avgas would become more available around the country, faster.

Agreed, only two airports off UL94 in Mass and I'm in the middle of them (~hour west or east). I have encouraged some more local but so far no joy :(
After cleaning all the lead oxide out of my exhaust ports (and the rest of the heads) I am really looking forward to UL fuel! Doesn't seem to be much progress on the UL94 map.