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Most all with Princton capacitive fuel level probes are already aware of this, but for anyone contemplating mixing fuels with one of these, readings will only be accurate with the fuel with which you calibrate it.

David A.

DCASonex wrote:Most all with Princton capacitive fuel level probes are already aware of this, but for anyone contemplating mixing fuels with one of these, readings will only be accurate with the fuel with which you calibrate it.

David A.

The ethanol in mogas will corrode the princeton probe rendering it useless for any fuel measurement.

I only use 91 octane mogass non alcohol free fuel except when away from home and can only get 100ll. the aerovee both aspirated and turbo like the no lead gas as opposed to the lead soaked 100LL. I don't get the soot and lead deposits from auto gas that I get with 100LL. One of the problems with the turbo has been the Valvoline VR1 interaction with leaded fuels,,,I wonder if this will later be a problem for the normally aspirated folks.

hope I can tag on to this conversation and refresh: I actually have a Jabiru 3300 with Aerocarb on my Rans S-7 (please don't hold that against me ;)

not quite sure the problem, but maybe if I toss out some symptoms I might get some of your thoughts on what to investigate

have been using a mixture of 100LL and mogas, which hasn't been a problem to date--hotter temps recently (and I'm in Colorado with DA 9500 today when I tried again) could be making a difference but I drained as much fuel as I could out of the tanks and added 100LL to see if that might help

symptoms remain:

engine starts fine, runs well for the 5 to 10 minutes it takes to taxi out, do a runup and be ready for takeoff

with time the engine starts to become more prone to hesitating when advancing power, becomes worse and seems to want to die when advancing power at lower power settings

seemed to start catching when I ran the RPM up around 2300 and up to full power--ie seems to run better at higher throttle settings but stalls out to rougher running at lower power settings

still not confident it would take to the air without incident--taxi back I am still puzzled

I may completely drain all fuel and try pure 100LL to see if the problem goes away

I am guessing I am prone to more problems at these DA's

What else should I check if fuel doesn't resolve it?

I'll start by removing cowling and checking all scat tubing and connections to the aerocarb. (I recently did an oil change which requires complete upper and lower cowl removal, disconnecting scat tubing connections to the muffler, and a fresh air intake to the carb.)

Guessing this is air/carb related or vapor lock but all fuel lines are insulated.

Don't think it's ignition but will check plugs, wires and distributor.

Not an expert by any means but I guess this is how we learn....

Thanks for any ideas!

Is this a new installation or have you been flying awhile and just encountered this situation?

You mentioned a cold air intake for the AeroInjector. One thing about the AeroInjector is it does not do well with pressurized air or ram air as that changes the fuel air mixture which the AeroInjector can not automatically adjust to.

Have you insulated your fuel lines and kept them away from the exhaust pipes?

Have you done a fuel flow test?

Have you checked the mixture settings as exactly specified in the AeroInjector manual? The AeroInjector is extremely sensitive to improper mixture needle settings.

I would check to make sure you are not running too rich as an initial check.

Please do not fly until you get this solved. Take it one step at a time. Do not try two "fixes" at the same time. You will have this figured out in no time.

Please do not hesitate to contact AeroConversions for help with the AeroInjector.

Please keep us updated on your findings and feel free to ask more questions.

Jake