Vapor lock?

[caymancraig]

Made my second flight yesterday and had the same problem as the first last week. Upon exiting the runway the engine died. Would not restart. Runs hot flying which I have to address, both head and exhaust(top of yellow on both). Starts up the next morning just fine. I have gone much richer to bring the egt down but didn't help. 60 degree day. Couldn't climb as less that 100 mph to keep from red line. Never a problem on ground running.

Wondering if vapor lock could be causing the stoppage. Turbo, 100ll, carb intake temp is 160 degrees. Oil temp about 170 degree.

Thanks all! Craig Mock, Naples, Waiex.

[NWade]

Craig -

Are you running an AeroInjector? If so, what steps in the AI manual have you gone through? With more detail, folks here may be able to help...

The only thing I can think of off the top of my head is: Have you tried leaning the mixture upon landing, to try to keep it running at/near idle? (But this is based on generic aircraft experience, I have not yet assembled my AeroVee Turbo)

--Noel

[jgpainter2]

Hi Craig. Mine will do the same if i don't lean upon landing. The aerocarb, at least mine, runs very rich at idle or thereabouts. i just pull my mixture out about 3/4 to 1" after landing roll stabilized. George N1020X

[Onex107]

Both answers above are true. With the #2 or #2.5 needle, adjusted for WOT, you have to lean, almost to cut off, to get a smooth idle. I have moved on to the #3 needle which has the best WOT position and the best idle position, needle thickness, close enough together to be in the Aeroinjector throat diameter. My best WOT mixture position is also the best setting for idle. Just saying.
But, I also went through a long struggle with the Burps. Vapor bubbles in the fuel line. It started in the air. I insulated everything, then it would happen after landing, when the engine compartment was heat soaked. Enlarging the cowl exit opening stopped that. The turbo adds a lot of extra heat to the cowl. I wonder if cowl flaps, on the top or sides, to allow outside air in during climb out or after landing would be feasible?

[gammaxy]

There's a lot of variables that go into tuning the Aeroinjector, so it's probably difficult to compare from airplane to airplane and definitely to the turbo. I have a Prince 54x46 p-tip propeller that only allows ~3150 rpm at WOT in level flight. If it spun faster at WOT, I'd probably need a richer mixture due to all the extra air. With my #2 needle I don't have any problems taxiing before or after landing full rich. I get a ~50rpm surge when I shut down with the mixture control.