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How to start the engine

mlwynn

Well Known Member
Okay folks, I may be having an 60's flashback, but I somehow got it in my mind that the starting sequence for my IO360 M1B with AFP fuel injection and dual Plasma III ignitions was supposed to include hitting the starter for a couple of blades and then turning on the ignition. Can't find anything about that in the Lightspeed documentation nor in the AFP documentation. Did I imagine this?
 
Haven't done that trick since I flew the Pratt and Whitney round engines on Beavers. I would stick with the normal... prime if you have it.
Crank and crack if you don't. 1/4 cracked throttle...
Judicious pump of the throttle if needed. If it backfires... keep cranking.
If the ambient air is really cold....figure a way (lots avail.) to warm the sump prior to starting... good for the life of the cylinder barrels too.
Nick
 
Lots of info on getting an engine started, have not heard of what you are describing at least not for an IO-360 with dual plasma and AFP injection.

In most cases your engine will be running before you get a chance to look at the second blade:). that is, if you turn the ignition on before cranking like most everyone else.

I see you are in San Ramon, is your RV located in Concord or Livermore?
Hope to meet you, lots of RVs on both of those airports.
 
I prime the engine 5-6 seconds with purge valve, WOT, reset throttle to about a quarter inch open, engage starter and push purge valve in at the same time.

Same procedure with hot engine except no prime.

Engine usually starts with a couple blades swung, sometimes more with hot start.

It's an art, getting the engine started. In time you come up with what works for you.

Amount of prime takes practice, priming with throttle closed does not work for me. Bypass flow rate is too slow. With WOT it is at least three times and gets fuel up there in 5-6 seconds. Do the same thing with throttle closed and my engine won't start.
 
I haven't seen a recommended procedure to motor the engine with mags off on a horizontally opposed engine. Doesn't mean it isn't out there but I haven't seen it. Different story on round engines.
 
Okay folks, I may be having an 60's flashback, but I somehow got it in my mind that the starting sequence for my IO360 M1B with AFP fuel injection and dual Plasma III ignitions was supposed to include hitting the starter for a couple of blades and then turning on the ignition. Can't find anything about that in the Lightspeed documentation nor in the AFP documentation. Did I imagine this?

Older Plasma ignitions don?t do well if the voltage goes too low when the starter cranks the engine. If the voltage gets too low, the ignition may fire at the wrong moment, leading to kick back. I have experienced this.

Permanent magnet starters in particular draw a very large amount of current at low rpm. The current decreases as the rpm increases, which means the voltage goes very low when you first hit the starter, then it comes back up as the engines starts to turn. So, if you have a PM starter, and an older Plasma ignition (as I do), the recommended procedure is to hit the starter button with the ignition off, then turn the ignition of after a couple of blades. My kickback issues went away when I adopted this start technique.

Apparently the newer Plasma ignitions have a design change that makes them more tolerant of low voltage, in which case it is proably OK to have the ignition on before you start cranking.
 
Service Bulletin: PL-1B

From the looks of it, you didn't imagine it: http://www.lightspeedengineering.com/News/ServiceBulletins.htm

MISFIRE DURING START
Service Bulletin: PL-1B

Date of Issue: 12/28/06 Supercedes SB: PL-1, 1/2005, Kickbacks
Subject: Misfire During Start
Models Affected: All Plasma CD Ignition systems prior to 12/2004
Models Not Affected: Plasma II+ systems version "PMS"
Plasma III systems version "U3+","A","A1", or "B"

Plasma CDI systems shipped after December of 2004, have shown no tendency to misfire or cause a kickback during start. This includes the current Plasma III versions "A" and "A1" and the current Plasma II Plus version "PMS".

On earlier Plasma CDI systems version "U3" or "U3+", misfiring is completely avoided if the key switch is paused for 1 second in the "Both" position before engaging the starter. Toggle switch operated systems have no tendency to misfire, (the issue was triggered by the rapid "on" / "off" / "on" sequence of the key switch motion).

All other systems can be modified to eliminate any possibility of misfiring. Contact LSE for further details. Unmodified systems shipped before 12/04, can misfire if the supply voltage drops below 8.5 volts repeatedly during cranking. This can only occur if the starter draws excessive current and the battery is not sized for that current requirement.

If you are using a small battery, we recommend using a wound field starter, as they draw less than 1/2 the current of a permanent magnet starter.
 
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