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Intermittent Lightspeed Ignition problem

Bsacks

I'm New Here
LS2+ for top plugs, Slick mag for the bottom plugs.
15 years and 1250 hrs in service
O320 160hp, carbed

A recent ignition check revealed the LS2+ running very rough. I have a tach for my mag and RPM indication for the LS2+. The mag was indicating normally and the LS2+ indicating 1/2 the RPMs of the mag.

I changed the spark plug leads and the problem went away for 1 flight, then came back. Changed the plugs and problem went away, then came back after 1 start. Changed the primary leads with exact same results.

Emailed Klaus at LS and got what I think is a generic troubleshooting guide not really related to my problem. I followed up with more specific question a few days ago and have heard nothing from him yet.

So, my questions to VAF. Has anyone experienced a similar problem? Also -and I think this is critical to my situation - Is the RPM indication from the Hall effect sensor what SHOULD be happening with the RPMs based upon crank position or what is ACTUALLY happening inside with the cylinders and plugs?

If the RPM indication is what SHOULD be happening then there is a problem with the sensor indicating and firing 1/2 as much as it should. If the indication is what ACTUALLY is happening then it might point to the coils, but I tested them and observed spark from the towers so I don't think the coils are the problem.
 
IF you have the Hall Effect module trigger in the mag hole, put a little pressure on the connector laterally - the connector/circuit board inside are known to cause exactly what you describe. Also, do you have older RG58 coil primary wires, or later RG 400?
 
If it is indeed the connector/CB I can outline a permanent fix on the connector - I suffered with the mag hole Hall effect module for 2,000+ hours before converting to direct crank trigger
 
Some thoughts.

The rough engine points to half the plugs not working. If you have a spare coil (all Lightspeed users need to have one, or better two, in the plane), install it. See if that solves the problem. These coils can be fragile, especially if you have a bad plug and/or plug wire the coil will degrade in a rapid fashion. As a side action, measure each plug and plug wire resistance if not already done. Replace as needed.

Pull the Hall Effect sensor and inspect. These are notorious for having leaking O ring oil seals (you are supposed to check it at every Condition inspection or 100 hours - or something like that.

RPM signal to your display comes from the box, not the Hall Effect sensor. The Hall Effect sender however is the source of the box for timing, so the box needs the sender to work for both timing and to provide your displayed RPM indication. Here if the Hall Effect sensor is not covered with oil, then I’d assume it is good. If the problem persists after you eliminated bad coil, bad plug and bad plug leads then you are at the point send the box back to Klaus.

Good luck…..
Carl
 
Lightspeed

The sensor on the flywheel I understand is far more accurate and less prone to problems than the Hall Effect Sensor. I've had the crank sensor for 9 years working without issue. You might find it would be a good move to make the upgrade.
 
The sensor on the flywheel I understand is far more accurate and less prone to problems than the Hall Effect Sensor. I've had the crank sensor for 9 years working without issue. You might find it would be a good move to make the upgrade.

^^^^ :):):):):)^^^^

You haven't lived until you've had the LSE Hall Effect module intermittent at night, IMC, over the Sierras. It's not more than a weekend of work to make the trigger conversion if you send Klaus your flywheel for magnet installation (or ring if using the new Mini sensor) in advance.
 
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I removed the Hall sensor and looked inside. Nothing unusual noted. The cable screws weren't as tight as they could have been, but that is all I found. Verified timing and spark from the coils.
I'll run it tomorrow. Will probably end up going with the crank sensor or another system. I just really want to find out what the issue here is.
 
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