Richard, thanks for letting know what the result was. I appreciate it. Must be a 3W thing. I got a CH ignition from Bill Carpenter. I installed and timed it exactly the same way I did the Rcexcel units and it ran perfect. I wish I knew what was going on.

Genuine C&H ignitions use a timing board made in the USA....Seems like it retards for starting at a lower rpm than the EXL clone..There are no more made in USA timing boards, so if you have a genuine made in Riverton Wyoming by Bill, your hand is safe...

Originally Posted by antique

Genuine C&H ignitions use a timing board made in the USA....Seems like it retards for starting at a lower rpm than the EXL clone..There are no more made in USA timing boards, so if you have a genuine made in Riverton Wyoming by Bill, your hand is safe...

Good info...make sure you come say hello I will be at the 3D line vending booth at the Nall.(or just flying)

Ralph, do you have any input on results of a weak magnet?

I have done some weak magnet testing. A strong magnet will spark when the magnet leaves the sensor edge. A weak magnet sparks when the magnet is halfway under the edge. That means, that the weak magnet has a shorter dwell time under the sensor (hall sensor "on" time, and the ignition may be in advance mode again (short time is high rpm). Add to that the fact that 3W uses small diameter magnets, which also make the ignition read shorter dwell times.
(just my educated guess)

So what you guys are saying is one might want to pull their magnet and put a new one in.

Dunno, but I got a nice and strong 1/8 x 1/8 magnet that I would love to send to a guy in the middle of this exact problem. New rcexl don't play, second one don't play, put in the magnet and see what happens.

This magnet was in a plastic bag. When I picked it up it took a folding allen wrench tool with it. Looked funny for that small magnet holding on to the big tool.

My engines 3w 120 ib2 rcgf twin ignition

Hi, I have a problem with the Rcxell ignition that I bought

For 2 days I tried to run the engine and almost broke my fingers due to the engine kickbacking, what indicates that the ignition timing was too advanced, but I checked several times and the angle was 28°, as suggested by the manufacturer.
I moved the sensor within the 20° to 30° limit, but nothing changed.
After that I tried to use the sensor that came with the Rcxel ignition in the package (before that I was using the original 3W sensor). The problem is that this Rcxell sensor has the S/N poles inverted, so I used the first magnet point of the engine (3W engines have 2 magnet points). I installed it at 28° before deadpoint and the second magnet point, but no success with either configurations. It keeps back kicking.
I moved the sensor until almost 0°, then the engne started to run, but obviously it doesn´t accelerate because the ignition is too delayed, it should give a spark before the piston gets to the top ( thus is recommended that we install it at 28°.
Eletronic ingnitions normally do atumatically retard the ingtion when at idle so that we can install it at 28° and still start the engine without getting a kick back from the engine. It should automatically retard the the sparking time when the engine is on idle, so apparently thats the problem with my product.
Conclusion: my ignition does not perform the auto-retarding of the sparks when on idle. Is it defective? How can I solve this problem?

3W has top dead center marks on them, One on the crankcase and one on the prop hub.

Line the top dead center marks up and post a picture of the magnet and sensor location and post it

In the last 10 years I have probably sold over a thousand 3W conversion kits with no problems.

Milton

Hello everybody! Did anyone try to put the rcexl 3w sensor in the same position of the OEM one? I got a rcexl ignition labeled for 3W, and I noticed that the sensor has 4 wires, just like the original one. Furthermore I can get a spark only if the sensor sees both magnets, in the correct spin direction. I know that universal single magnet rcexl ignition (3 wires sensor) calls for 28° BTDC, but I can’t find anywhere a manual for 3W version. Is it possible that this version is made to use the original sensor position, with the second magnet just a few degrees BTDC?
I wrote that post just yesterday in another thread, which is more recent, but I was a bit off-topic. I think this thread is more appropriate. And I did a step forward. I started my engine, a new (old) 3W 75us, with the rcexl ignition for 3w. The sensor barely fits original holes, but I tried it as it comes, before going mad with zip ties and new holes in the crankcase. And surprise! After a few flips with choke, the engine started on the first flip without choke! It gains rpm smoothly, without loss of power! Definitely it is not out of timing!
So maybe these “new” 3W labeled Rcexl ignitions are designed to be plug n play swaps, without tapping new holes and loosing mind on timing!
I post a picture of the magnets and sensor position on the TDC and a video of the first run of the engine.

First run

3W engine with Rcexl ignition (1 min 19 sec)

It must be close to 28*,but you should time it to see where it's at.

I have the first magnet (green one) at more ore less 30° and the second (red one) at more or less 0°. Same as the original 3W sensor

Bolt it on and be at 30*,don't get better than that.I had no idea that rcexl made a direct replacement sensor for 3w.