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Hot Start with E-Mags?

I recently purchased an RV 7A. It has fueL injection, one conventional and one E-mag. The other day someone suggested I never use the tried-and-true hot-start method to start the plane; that it is harmful to the E-mag.

Thoughts?

Thanks, sle
 
I have an E Mag and magneto on my RV6 with fuel injection. My hot starts I always start at idle cut off and the throttle open a little. This is the same way I started it with 2 mags.
 
Plus 1 on that.....

Starts perfectly, however......

If you have stopped for say 10 minutes, when you start again, there may be some stumbling and missing for a few minutes - just vapour in the lines as the Lycoming doesn't have a return loop system.
 
Wouldn't it be logical to expect Emagair to note that a particular hot start technique is a problem? Yet they don't. Call Emagair and ask them. I would bet that your "source" at the airport also thinks LOP is a bad idea
 
Must research the source and use judgement in accepting advice like this. Many suggest that walking under a ladder will create adverse consequences.

I remember my transition training CFI adamantely suggesting that I prime my carb'ed engine by pumping the throttle. Most know that when this is done with the engine not spinning, it loads the FAB with raw fuel and creates a serious risk of engine fire if you get a backfire. While the CFI had no idea how an engine worked, he had heard this so many times that he assumed it had to be correct. How could it be wrong when every car produced before 1980 was started this way?

Larry
 
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My technique

FWIW...

Lyc IO-360 M1B, one slick, one Pmag.

Hot start technique.....

Boost pump....ON
Throttle.........WIDE OPEN
Mixture..........FULL RICH (2-3 SECONDS)
Mixture..........ICO
Throttle.........CLOSED
Boost pump...OFF
Throttle.........1/2 OPEN
Starter...........ENGAGE
Mixture..........SLOWLY ADVANCE AS IT BEGINS FIRING
Throttle..........REDUCE TO IDLE

This works for me every single time. YMMV
 
Thnx Steve/All. Steve’s method sounds like the best path. The person who warned me against it had no maligned intent and is not, to the best of my knowledge, superstitious. Perhaps he is, like me, still trying to learn about non-cert aircraft’s idiosyncrasies.
 
Taken by me at a Lycoming seminar given at OSH in 2016...works perfectly, every time. ('Scuse the baseball capped noggin...)

Looks like Steve was either at the same seminar or has tribal knowledge superior to mine...

Rob


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checklist

Taken by me at a Lycoming seminar given at OSH in 2016...works perfectly, every time. ('Scuse the baseball capped noggin...)

Looks like Steve was either at the same seminar or has tribal knowledge superior to mine...

Rob


i-hMgZvX2-L.jpg
Does moving the mixture to full rich for a few seconds with no boost pump running do something, or is this dependent on the type of FI you are running?
i-hMgZvX2-L.jpg
 
The described Lyc. hot start methods here have been successful for me over the past 40 years. I suggest one deviation however; I retard the throttle before advancing the mixture to avoid a roaring start and the resultant blasting of debris onto anyone behind me. I find there is plenty of fuel in the system that a slightly delayed mixture advance is not detrimental.

George
 
FWIW...

Lyc IO-360 M1B, one slick, one Pmag.

Hot start technique.....

Boost pump....ON
Throttle.........WIDE OPEN
Mixture..........FULL RICH (2-3 SECONDS)
Mixture..........ICO
Throttle.........CLOSED
Boost pump...OFF
Throttle.........1/2 OPEN
Starter...........ENGAGE
Mixture..........SLOWLY ADVANCE AS IT BEGINS FIRING
Throttle..........REDUCE TO IDLE

This works for me every single time. YMMV

THROTTLE .....1/2 OPEN? Do you mean half inch? Or actually half throttle?
 
Does moving the mixture to full rich for a few seconds with no boost pump running do something, or is this dependent on the type of FI you are running?
View attachment 408

It might be affected by the FI system you're running. For example, having the mixture at ICO with a Airflow Performance FM200A doesn't actually seal anything off completely. ICO on the system just makes the mixture so lean the engine can't run. This is why I get gas dripping out of the sniffle valve at the end of a flight, and why AFP offers a purge valve, which I don't have if you really want to "turn it off". I use the forementioned technique without the "mixture to rich" step and it always works for me. I don't think there would be any pressure left to release in my system...
 
THROTTLE .....1/2 OPEN? Do you mean half inch? Or actually half throttle?

Yes, actually 1/2 throttle. I think I remember reading somewhere to use FULL throttle, but I have heard of bad things happening using that procedure.

You just have to be ready to bring the throttle back to near idle as the engine starts. If you were standing next to my airplane when I do this, you would never know it was anywhere above idle.

Again, I am no expert on this...I was taught this procedure from other more experienced than me. But it does work every single time
 
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Just another data point - Like others only I leave the boost pump on during crank from ICO. Mixture full rich 5-7 sec (depends on how cold it is), 0 sec on a hot engine. Diamond Aircraft’s test pilot recommended this as how they start their IO360s. Works good. Precision Airmotive Silverhawk fuel servo in mine.
 
Seems odd that the hot start instructions do not indicate to run the boost pump with the purge line open just before starting to eliminate hot fuel and vapor. Isnt that what the purge line is for, to help with hot starts?

erich
 
Seems odd that the hot start instructions do not indicate to run the boost pump with the purge line open just before starting to eliminate hot fuel and vapor. Isnt that what the purge line is for, to help with hot starts?

erich

Not everyone has a purge line.

I have one, but if I just topped the tanks, running it to purge fuel just dumps fuel out the fuel vent.
 
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