What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

EI kickback

Capt

Well Known Member
Hi guys/gals.
I've got an IO360 180 HP with 1x Bendix Mag & 1x Plasma 11 ignition. When I go to start it cold after the usual prime using the Std Lyc procedure the prop kicks back just about everytime, I then rengagd the starter and it cranks/starts fine. Getting worse of late. Non impulse Bendix mag timed correctly. I use the Cessna type ign switch (I didn't build my 8)....any ideas guys?
 
As mentioned non impulse MAG. Something has changed to create an excessive advanced spark? I think I'll try grounding the Mag out seperately.
 
Try cranking with the ignitions off before priming.


Then try to start normally.


My thought is something is sticking inside the ignitions on the first attempt.

Cranking first might unstick things...........
 
I can't crank with ignition off, wish I could.
I could crank without priming so no fuel to create a kickback, that might 'unstick' something, ll try that next.
 
Might be worth a try to ground the right mag and try a start.

If that solves the problem, check your P Lead and / or ignition switch.
 
EI kick back

If during first start atempt, the prop stops and then you get a kick back,
it is very likely that the EI capacitor can't hold the charge and a spark is released before top dead centre. I had this problem and I trashed the starter and the starter support gear. IO-360 180 hp.
I have a lithium battery and it never gave full power during first start atempt.
Second start atempt always worked well.
I replaced the ACS start lock (OFF/L/R/BOTH/ START) with two ON/OFF switches and a separate start button. I have the sure fly EI and I have set the right mag to 30 deg advance and clocked it 5 deg AFTER top dead centre.
So real advance is 25 deg once the engine RPM is more than 400 RMP.
I allways start on the right EI.
This has worked well, no more kick backs.
 
Hi guys/gals.
I've got an IO360 180 HP with 1x Bendix Mag & 1x Plasma 11 ignition. When I go to start it cold after the usual prime using the Std Lyc procedure the prop kicks back just about everytime, I then rengagd the starter and it cranks/starts fine. Getting worse of late. Non impulse Bendix mag timed correctly. I use the Cessna type ign switch (I didn't build my 8)....any ideas guys?

If it won't get over the compression stroke on the first try consider replacing the starter with something better and/or getting the electrical system up to snuff (battery/cables/contactors/etc) as well as following some of the above advice.
 
Last edited:
Hi guys/gals.
Non impulse Bendix mag timed correctly. I use the Cessna type ign switch (I didn't build my 8)....any ideas guys?

It is your non-impulse mag that is causing the kickback. Reconfigure your switches so you can start on the Plasma. The Plasma reliably fires at TDC during start so there is little possibility for a kickback. The non-impulse mag is firing 25 deg before TDC and likely causing the kickback. You want that one off for engine start
 
Capt,
I was running one Lightspeed Plasma 3 and one non impulse mag. My friend the builder had this happen and occasionally I had it happen. After a lot of frustration, my friend learned that it is the Electronic ignition. He told me that the EI needs to be powered on, but then to wait for maybe 30 seconds before starting. Because the EI needs to go back into a start mode. If you don't wait and let it reset, it will fire at 30 plus degrees of advance. My builder friend told me he learned this finally after speaking to Klaus but after much frustration. Also, he never mentioned just how long you should wait to let it reset though. And I have never been able to find anything in the manual.

Everything is always speculation and I am not a betting man, but I would put money on your EI box is not resetting into start mode.

Edit:
I just read Kents post above me.
I'll bet anouther bet that his keyed start is already grounding out the mag during start. (Easy to check for grounding on the back of the keyed switch).
If the aircraft was never set up with the non impulse mag already grounding the thing would have been doing this since day one.
 
Last edited:
He told me that the EI needs to be powered on, but then to wait for maybe 30 seconds before starting. Because the EI needs to go back into a start mode. If you don't wait and let it reset, it will fire at 30 plus degrees of advance.

Hmmm. Not saying you're wrong about this reset thing but it's not something I've encountered and I've been messing with them for a while. Yeah, Klaus is rather close-hold with his information but I would think it'd be in the manual.

Maybe his switch is not grounding out the non-impulse mag in the START position. I think the mag could be grounded between mag and airframe for a test or grounded with a jumper wire on the mag post of the switch to the airframe and see if it starts normally with the Plasma, or disconnect the starter and check around.
 
Starting

Turn off the non Impulse mag and let the engine start on the electronic ignition. Mag on after start- not sure how the Plasma ignition works but prob similar to Electroair on my engine and my buddy’s RV-10.
 
Thanks guys for the suggestions etc, some things to think about there. It's odd that it doesn't do it all the time or on every cold start? Battery has been replaced recently and it has a very healthy lightweight starter, the combination spins the motor over like a top once the first kickback has been experienced and when it's hot.
I did have a problem with the Cessna style ign switch ages ago, the magic smoke came out of it but it was pulled apart cleaned checked and reinstalled, just wondering whether that has now set up an intermittent fault not grounding the Bendix Mag during start?
I'll get started on the suggestions, thanks again guys, gotta luv Vans forums for assistance-)
 
Capt,

From LSE website. This procedure 100% fixed my issue. I pause for a three count immediately before cranking.

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


Link: http://lightspeed-aero.com/News/ServiceBulletins.htm
 
Guys today I did all the usual pre start stuf, prime, crack the gas pedal, mix idle cut off, ignition switch to both, paused for 30 secs hit the key and wham! No kickback and started instantly! -) that's just one try, I'll try it again when next I'm up at the hangar and its stone cold.

Thanks to everyone especially the turn it all on and wait suggestions, hoping that is the fix-)
I'll be back -)
 
Last edited:
Primary reason for a kickback is a weak battery. You should be able to read 12+ volts at the starter terminal during initial engine start. The non-impulse right mag has no effect on your engine start when using a standard Cessna type ignition switch. It doesn’t provide a spark to those extra spark plugs on the right mag until you have released the start switch. At this point you should be 400+ RPM (engine start sequence) and will enable magneto ignition on the right mag when you release the ignition switch to both.
If you want a strong start, make sure your battery is up to snuff (more important in colder temperatures), and make sure you have a good engine/airframe ground - like a 2awg ground strap. A lot of us use two engine to airframe strap grounds, because this is so important for all sorts of things.
 
Last edited:
Second cold start using the modified principle and bingo, no kickback. That was the issue all along, gotta wait a few seconds turned to both before starting.
Thanks guys, some saved me many dollars and much grief -)
 
Back
Top