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Which fuel does the Mosquito(s) burn?

This question may have been answered before but I tried my best searching so maybe someone is kind enough to answer again...

I'm interested in getting myself a Mosquito in the near future and choosing the right engine is all about what fuel that's most available and affordable in my area. So the big question is, what fuel is accepted in the piston- and gas turbine engines?

I've understood that for the piston engines (MZ202/Inntec 800) AVGAS 100 LL and AVGAS 91/96 UL is mostly acceptable as fuel, but can you also run MOGAS (gasoline for your car) as well?

If I'll choose a turbine engine I'd go for the Solar T62-2A1... so, Jet A and Kerosene is fine... but what about Diesel?
I run pure gas 93 octane and have a Hirth engine, If you look thru the forum you can find answers to most of your questions.
But if your lazy like me just ask

In the piston engines it would be better to run mogas. The 100ll and 91/96 avgas are expensive and contain very high levels tetra ethyl lead which is not necessary for combustion flamefront control in low hp engines and low level flying.
I'm sure there are more knowledgeable engine-heads around here than I am, but I didn't see any definitive answer.

For the turbine you can use Jet-A, diesel, kerosene, used motor oil, cheap vodka, ... it's not that picky.  Don't know about the MZ engines.

The 800cc engine was designed for the global market so it is supposed to be happy with whatever gasoline is readily available.  In theory, the EFI ECM computer will compensate for variations in octane, up to a point.  The Service Manual says "The recommended gasoline to use ... is 91 octane (minimum)."  In a four-stroke, too high an octane is less likely to destroy your engine than too low an octane.  Don't really know if that applies to two-strokes but you still don't want detonation.

It also says that up to 10% ethanol is "acceptable" but I've been using only ethanol-free 93 octane just to be safe.  My plugs are clean and the EGTs are even, stable, and about 100 F below the 1100 F setpoint.

Currently I'm still schlepping five gallon gas jugs around.  When my flight test hours have been satisfied, I'll be flying mostly to airports and will be using 100LL, as it's the only avgas available in my region.  I'll report on any lead-fouling I find in the spark plugs or unusual EGT readings (it should burn cooler).

I'd be grateful for any reports from XE-285 pilots using 100LL.
-Chip Davis-
N8421L 2016 XE-285 #1076

I completed my 50 hr/annual inspection and finally went to KFTG just up the road to purchased some 100LL. I farted around for about a half hour and the max EGT readings were 924 and 969. Water temp only got to 63. Mind you I never got over 35 IAS on a 67 degree day at 5,300 ft. max. I pulled the plugs and they looked good. Conditions were on the windy side just ahead of an incoming storm. I'll let you know more when the weather is more favorable.

XE 285  1205 (Myrtle)
Start: 8/1/2013
Finish: 5/24/2014
Arrived home: 10/11/2014
Mike, where do you have your fuel mapping set? Flew mine this morning and only saw 860 on the egt, guess I need to add some fuel.
If you want it to run hotter, I believe you will need to "lean" it out. I am currently
running at +20%. Might need to lean it out a bit while running 100LL. After letting it idle for about
30 sec., I would try to throttle up and the engine would "bog" first then start to increase RPM.

XE 285  1205 (Myrtle)
Start: 8/1/2013
Finish: 5/24/2014
Arrived home: 10/11/2014
Yeah, but at the factory they told me th 285 needed to add fuel to increase egt, didn't make any sense to me either. Your at 20 across the map?
Might need to go that way myself, my egt's were around 860 for this mornings flight. Need to get them up a bit. Dave
To increase EGT you have to lower the map number... I'm down in single digits to get my EGT around 1000-1050... I'll post a screenshot of my map...

Sent from my iPhone using Tapatalk

[Image: d2267f6ea2032007140a3095a6f22001.jpg][Image: 31e40b801f46703c363457cd6f7bdbdf.jpg]

Disclaimer: This map works for my machine, might not work for others... I also adjust each cylinder separately, this allows me to have both cylinders running at nearly the same temperature... I'm also only 300' above sea level and the OAT for this map was 85F...

Sent from my iPhone using Tapatalk
(06-03-2016, 05:42 PM)Dave R. Wrote: Yeah, but at the factory they told me th 285 needed to add fuel to increase egt, didn't make any sense to me either. Your at 20 across the map?
Might need to go that way myself, my egt's were around 860 for this mornings flight.  Need to get them up a bit. Dave
Team, please forgive me if this is  too long-winded.  And even if you read and believe the whole thing, you may still have trouble solving air fuel management on your XE 285.

Dave and Mike, you could both be right, although I am placing my bet with Mike.  Here is how to tell what is going on.  Read John Deakin's Pelican's Perch articles, (here is one article, Pelican's Perch) which were for 4 stroke aircraft engines, but similar principles apply here.  On any engine, if you were start from an extremely rich fuel air mixture, at a constant altitude, outside air temp, throttle setting and rpm/manifold pressure...And then gradually lean the fuel mixture, your would see a rise in EGT and an increase in power up to a point, say 100 degrees rich of peak EGT, and if you continue leaning, the EGT will stop rising at the "peak" and then EGT will fall as you over lean on the lean side of peak with a reduction in power. On the lean side of peak, you are losing power and cooling with excess air.  On the rich side of peak, you are cooling with excess fuel with very little power loss.  (Spark plug fouling and ring sticking risk are greater with richer mixtures).  If mixture distribution between the cylinders is not balanced, where one cylinder is leaner or richer than the other, power losses will be greater and you could be at risk for one cylinder being too lean and the other too rich.  This can easily be seen with digital egt/cht for each cylinder and digital fuel flow, which I had on my Cirrus SR22, but maybe not so on your XE 285s.

So, if in fact, you observe that increasing fuel increases EGT based on your baseline condition, then that means you were running too lean and were operating on the lean side of peak EGT.  On the other hand, if adding fuel were to cause a decrease in EGT, that means you had previously been operating on the rich side of peak for optimum cooling and lubrication.  
I am no expert in two stroke fuel injected engines, but believe that we would want to operate on the rich side of peak to insure good lubrication and little to no loss of power.  Therefore, if factory settings were intended to be on the rich side of peak, then Mike's assumption would be correct.  I am no expert and you may argue otherwise.

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