Newbie question here. Do most electronic ignition systems work the same and are they interchangeable (except for plug type that is ). Do they basically have the same auto advance or retard features? Or do they only go one way ? Is there a way to find out? What about the amount of advance/retard, is it incrementally the same for all systems or are they tailored specifically for certain engines like are the advance/retard vs rpm curves the same and the amount of advance/retard angle(e.g 20,30deg)the same?

Just for my sanity,if a system has only an advance feature then may I assume that the sensor has to be at almost TDC and if it has a retard feature then it has to be in the before TDC position?

Reason is I am in the process of getting a replacement ignition system for my G20. I am thinking of using the rcexl from a friend or getting one after market variety but don't know if it'll work and if I can use the same sensor or at least the same mounting holes and if the performance will be the same.

Any help appreciated.

To many questions, but simple answer to your problem is that the RCEXL is a direct replacement for the Zenoah. You can use the Zenoah sensor, but will have to change the connector. The Zenoah color code on the sensor matches the newer RCEXL color code.

The auto advance simply delays the timing and adds it back with detected rpm, so with those systems, you set you timing at 28 to 32 degree's, and the box does the rest. Just set those so when the crank passes the 30 degree mark, it sparks the plug, and thats close enough. Some engines have a mechanical advance, so they use a different box with no auto advance function. As long as you use the correct box for you situation (auto or mech adv) you'll be fine. With mechanical adv, I like to set the timing by fully advancing the timing mechanism, and setting it to 30 degrees. Timing at idle winds up being around 2 to 5 degree's when I do it that way. Im more concerned with the full advance, and not so much what it idles at, but 2 to 5 degree's BTDC at idle is the norm.

A million thanks TKG you're the man!! Problem solved QED!

Thank you too freeonthree for your description.Still digesting, sorry I've always been slow.

Now for a bit of general knowledge.Are most ignition systems built the same way? i.e same advance/retard curve,advance/retard angle, do they advance and retard or only go one way electronically? Can I plonk in an ignition system from a junked motor to another brand of motor and will it run?



Very sorry, too many questions again.Need help from the experts.

Oh boy ! he got lucky... that was great info !

Three types I've seen.

3W uses a two magnet system. The guy that sells you the engine won't tell you how to time it though LOL.
NP CH ignition ignores the first magnet and outlasts the 3W ignition anyway.
ZDZ and others use a type that you set about 6mm advanced and somehow remembers when to spark and get advance on the next revolution.
CH type you set at 28 to 30 degrees and electronicaly retards spark when rpm's reach below about 3500.

So you can kinda tell what type you have by it's placement at TDC. If it's about 30 degrees it's a retarder. If it's about 6mm it's a rememberer.

Got a question for you.

If the C & H retards the timing below 3500 how can you set the timing at 28-30 by slowly turning the prop and watching for the spark. Wouldn't the spark be retarded at this slow rpm thus showing you the retarded degrees and not the advanced degrees ? Does my question make sense?

Computer are wonderful. the CH unit hase a chip built in the knows all. Below 180 rpm its fully advanced so you can set timing and above thea its fully retarted untin the engine is going fast enough for the chip to start advancing the timing.

Thank you, I've always wondered about that.

This is good info. Thank You.

BTW only thing bad about gas is the use of the word RETARD. Can make some guys mighty angry!!

I thought I would bump this up to date....so engine owners can figure out how to set the timing on CH & simular systems. I do think it could have been worded a little better!!! Capt,n

hay i need a ing for a zdz 160 bought it at the joe nalls from tbm and they forgot the ing in the box now they wont honar it so new engine no ing what is a replacement for this ing for this engine

Who is " tbm" ? Maybe they will get you that Ignition....but you may need to turn up the heat!!! Good Luck Capt,n</p>

http://www.ch-ignitions.com/
ZDZ has good ignitions too. Might evan be better than CH cause I believe their advance is on a curve, where-as CH has an advance to full at about 3500 rpm. It's just so easy to call CH and have them send you one. CH ignitions are also repairable, ZDZ is a sealed unit.

The CH units begin to advance at 1100 rpm and reach full advance at 4000 prm. The advance is a linear line with an infinite number of steps.

O boo hoo now everyone knos. I thought it was black magic
BCCHI

tbm = Troy Built Models. They took over from RCS.
I can't imagine that they would leave out the ignition on a purchase like that.