Hi I am the MD of OPTIFUEL and came across your photos. The photos tell it all really, massive rust issues which I suspect seized the bearings hence the failure. OS recommend 18 to 20% synthetic oil. W use only KLOTZ products in our fuel which is known to be the world leader in synthetic oils for mixing with Methanol and Nitromethane. The oil has incorporated rust inhibitors in it but these are not designed to stop rust forrming if fuel is left in the engine.
Irather supect that this engine has had unsed fuel left in it and this has damaged all the carbon parts leading to a catostophic failure. Extract from typical OS manual. 18 to 20% oil and engines are delivered with needles set to 15% nitro with 20% oil.
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<font size="1" face="Helvetica"><font size="1" face="Helvetica"><p align="left"><span style="font-size: larger">The FS -56 should be operated on a methanol based fuel containing not less than 18% (volumetric) castor oil,or a top quality synthetic lubricant (or a mixture of both),plus a small percentage (5-20%) of nitromethane for improved flexibility and power. (The carburetor is adjusted a little on the rich side at the factory for a fuel containing 20% lubricant and 15% nitromethane.) Some commercial fuels also contain coloring additives as an aid to fuel level visibility. In some cases, these additives have indicated slightly negative effects on the performance.</span></p></font></font><span style="font-size: larger"><hr />We ship hundreds of thousands of litre of fuel per year and in Europe all the top Helicopter, fixed wing and car drivers run OPTIFUEL with very few issues. I think the engine you we sold as new must have had fuel left in it sadly and the result was terminal.
When you finish flying run the engine dry so it will not start, turn prop CC to compression and plug pipe with suitable bung. If the engine is left for any appreciable time use after run oil. Methanol is hydroscopic (will attract moisture) and if this occurs the methanol/moisture and nitro mix to make weak nitric acid and it is this that damages the carbon parts.
I hope this is of assitence.
Regards
Andy
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