Hey guys, I saw this post a few days back on another forum... have a read.. this guys has a Jabiru.
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Fuel for Thought
Another gremlin has appeared lately; an especially destructive little monster which has started
chewing on fuel tanks, causing leaks. Because formulations vary so widely I normally don’t like
naming names, but in this case it does appear that Shell V-Power (98 RON) is a common factor in
many cases. Indications are that this fuel (and others like it) contain a relatively high proportion of
Aromatics: highly volatile compounds, including nasties like Toluene. Unfortunately, the sealant
used in our fuel tanks is not suitable for use with compounds like this: Toluene is often used as a
cleaner or as paint thinners and is pretty aggressive stuff!
Most issues seem to occur in cooler climates where a highly volatile component like Toluene would
make sense in assisting cold starting your car after it was parked in the snow all weekend – but we
recommend that all operators review Service Letter JSL007, understand the content, the
compromises and risks inherent in using automotive fuel. It’s strange to be feeling nostalgic about
the “good old days” when the most destructive component of MOGAS was Ethanol, but here we are:
there’s progress! Remember, the days of “fill and forget” are gone: there are many traps waiting to
bite if you take the contents of your tank for granted.
In response to the leakage issues we’ve started a new round of testing with a sealant which we are
promised is the last word in chemical resistance: proof against fuels, volatile hydrocarbons and even
acids. All going to plan, we will release this product to service as soon as testing is complete. Early
indications are that this compound will also be suitable as a retrofit, to re-coat tanks currently using
other sealants. In the interim I’d recommend using a 95 Octane fuel instead of 98 as they appear to contain less
destructive aromatics. Of course, good old AVGAS is still a lovely stable fuel which doesn’t attack
anything but your bank balance – but we realise that it’s not practical for everyone.
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