Engine starting - FINALLY figured out!

I have followed the Lycoming manual to a T for cold engine starts and it has never been satisfactory. Maybe someone will see all this and provide some grand insight and show that I was doing wrong to begin with, but anyways the standard Lycoming way by the book goes something like this: 

  • crack throttle 1/4", mixture full, boost pump 3-6 seconds, mixture cut-off, crank, raise mixture slowly as begins to catch.

Thats what is suppose to happen but what happens at the crank stage is crank crank crank crank crank.. and then I finally stop because its not working. I crank again and then it finally starts, or sometimes a quick boost (1 second), and then it cranks right up. Arggg! I've tried making minor tweaks to this process, but always with the same general approach because its by the book. 


I finally figured out something that works much better with our system, which is two slickstart mags (no impulse coupling) and a slickstart shower of sparks booster. Heres how the new process goes: 

  • throttle 50%, mixture 50%, boost 5 seconds, then crank. It cranks right up and I then immediately reduce throttle to idle. 


Just wanted to share in case anyone else has similar frustration. Comments are welcome. 

Comments (1) -

  • Standard Slick installation on I0-540 D4A5 RV10.  400 TT.  Figured it out by 200 hrs (slow learner).

    Cold start.   Mixture full rich, throttle 1/4.  Boost bump 5-10 seconds, depending on ambient temp. I live in Southern Ontario so winter cold would be -10 C for 10 sec and summer cold 20-30 C for 5 seconds.  Other temps in between 5-10 sec.  Not critical to starting if I pick a second or two +/- ideal, just a few more blades before catching or a bit of a rev surge if a bit too much prime.  Starts within 2-3 blades every time with this routine.

    Hot restart per Lycoming, more or less.  Mixture closed, Throttle closed, boost pump 2-3 seconds to get full PSI showing on guage.  Open throttle to 1/3.  Crank and open mixture.  Starts at about the "M" on the quadrant, I push a bit past as it revs up, then back to ground lean.  I always run aggressive lean on the ground.

    Warm start.  This is where the "art" seems to be, depending on how long since shut down and ambient temp.  Same routine as hot start.  If it doesn't catch after a few seconds, close throttle and mixture, boost pump again to get PSI to top, throttle back to 1/3 open, crank and open mixture again.  95% of time it starts after a couple rounds of the prop.

    Roger Randall
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