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Plasma11

Capt

Well Known Member
Thought I'd kinda re hash this problem here I've got in case some fresh minds pass by.
I have a Plasma 11 on the r/h side of a Lyc IO360 and a S4LN-21 Mag on the left side.
When cold say for the first start of a morning after priming I always get a kick back, sometimes several times before it spins over continuously and starts.
Got no issues, Std Lyc hot start proceedure. Most likely a timing issue but not sure. The Bendix Mag has been checked and working, the Plasma I'm not sure about. Will disconnect each one in turn to see what happens but thought I'd pass by here first, anyone? Batt/starter not very old.
Thanks.
 
Kick back

You say kick back. Does this mean the starter is being reversed as the engine mis fires? If so this is not normal and can cause damage or get you stranded with a broken starter. I would not accept a kickback. I dont think I have ever had one when flying behind mags. JMHO.
 
How are you enabling the LSE and mag when starting? The standard Bendix keyswitch or individual toggle switches?

Many, many years ago (before Klaus built my first LSE which was early 90's) he made a change in the software that prevented what you are experiencing. I currently fly a Plasma II on the right and an impulse coupled Slick on the left side. Klaus made (makes) separate models for Bendix switch start (not his recommendation) or separate mag toggle switches. Are you sure you have the right LSE configuration for your installation?
 
New install? If so, I suspect you timed the LightSpeed at 25 degrees BTDC instead of TDC. If so the resulting timing would be ~50 degrees BTDC.

Carl
 
Didn’t LSE have a notice about the older models asking users not to go straight from OFF to Start, but to pause at BOTH for a second to not confuse the module? Either way, a kick back can break the starter, and I’ve heard that it could also break the boss off the engine case! Do not keep flying it until you figure it out.
 
Didn’t LSE have a notice about the older models asking users not to go straight from OFF to Start, but to pause at BOTH for a second to not confuse the module?

Yes, Tom is right! This has been discussed on this site before. I spoke with Kraus years ago about this. My kickbacks 100% stopped when I started stopping at “BOTH”, counting “Thousand one, thousand two, thousand three”, then “Start”. No more kickbacks.
 
Let's hope the OP is using LSE's crank trigger, and not the mag hole Hall Effect module.
 
Thanks for the feedback thus far guys.
I bought the plane 3+ years ago with the current set up of 1x Plasma & 1x Bendix Mag. It's always done it from day one only when I start cold, hot has zero issues.
The ignition switch is a Cessna type but I think I'll have to start isolating each system one at a time to determine the offending side.
I'm aware of the 'pause' trick but that makes zero difference -(
Warmer months it's not as bad?
Thanks again guys I'll have to get serious and start pulling it all apart and starting from scratch-(
 
Ignition switch wiring

JUST A POSSIBIITY (and you probably have already considered this):

When wired in the normal fashion (to accommodate the normal single impulse coupling), starter switches ground the right mag (or E.I.) when in the "start" position (it's easy to omit this separate ground wire). Having this ground feature wired in facilitates starting on the left mag only, which is where a single impulse coupling should be located (some aircraft have dual impulse couplings, in which case one would not want this feature activated).

When starting on the left mag only, there is obviously no timing conflicts between the redundant ignitions. And as soon as the engine starts firing on the left mag, one relaxes the "start" position and goes to "both" and the engine is up to 500 rpm in a second or two and, if timed correctly, both sides are sparking their plugs pretty much at the same time.

The above nothwithstanding, the key switch possibility does not explain the cold vs hot starting differences.

Good luck,
Larry
 
The left mag has no impulse capability and the ign switch is wired to start only on the EI only. I've got the ign switch wiring diagram and it is set up to ground the Bendix nag in the start position, the problem must be in the Plasma?
The other day my 8 sat outside in the Sun for nearly two hours, whilst still winter down under and cold it started a bit easier than normal this time of the year? That small bit of warmth seemed to have some bearing on it?
Anyway I've pushed my plane to the back of the hangar for now and will fly one of my other more reliable machines till the summer.
Again thanks guys for the feedback -)
 
Call Klaus

Your best bet is a call to Klaus at LSE or email.
He can pin point your problem in short order.
99.9% of all issues with his ignition are installation errors.
What you describe is definitely not normal and as others pointed out could get you stranded with a broken starter or ring gear.
I have the same set up as you but my magneto has an impulse coupling
and I installed toggle switches as per LSE's installation instructions.
I always start on both ignitions and never had a kick back.
One of the great features of the LSE is its retard capability for easy starting.
You definitely want to use the LSE for starting.
I am certain Klaus Savier will be able to help you solve your problem.
Have your questions ready, he is not one for a lot of small talk.
 
Your best bet is a call to Klaus at LSE or email.
He can pin point your problem in short order.
99.9% of all issues with his ignition are installation errors.
What you describe is definitely not normal and as others pointed out could get you stranded with a broken starter or ring gear.
I have the same set up as you but my magneto has an impulse coupling
and I installed toggle switches as per LSE's installation instructions.
I always start on both ignitions and never had a kick back.
One of the great features of the LSE is its retard capability for easy starting.
You definitely want to use the LSE for starting.
I am certain Klaus Savier will be able to help you solve your problem.
Have your questions ready, he is not one for a lot of small talk.

Be sure you read the manual before calling Klaus :D
 
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