Changfa wiring

[KellyR]

Hello!  I've got a Changfa clone (Jiang Dong) that I'm fairly happy with, though little things keep breaking down on it.  The ignition switch went into the waste basket so I had to get a push button starting switch.  It was the only thing I could find and works.  But, and it's a big but, the old keyed ignition switch had three wires coming from it.  One went to the voltage regulator to charge the battery.  With two wires now coming from the push button switch, I have one going to negative and one to the big bolt on the solenoid (starter side), which is positive.  My question is how to wire the ignition with that two wire switch so that the battery gets charged too.  There are some electrics I can do, but this isn't one of those things.

Thanks in advance,

Kelly

ps.  It's a 7.7hp engine running a 5kW ST generator (yes, engine too small for max power) via belts. 

[mike90045]

You need a 3 wire switch starter switch.
 1 wire is common (hot, 12V)
 1 wire is Starter Motor (start) (momentary)
 1 wire is alternator engage. (run)

You could do this by adding another switch for the alternator, BUT, you have to switch it off when you shut down the genset, otherwise, the alternator field will drain the battery overnight.

[mjn]

Here is one way to wire a Changfa engine:


Since you don't have the original switch, you can make do with two SPST switches (two wire).  One is the "start" switch (preferably momentary), and the other is the "charge" switch.  Both switches have one side tied to the plus side of the battery.  The other side of the start switch connects to the small terminal on the starter.  The other side of the "charge" switch is tied to the output from the regulator.  (On my engine, the regulator output is a red wire.)

After starting, close the "charge" switch which connects the battery to the regulator.  When you turn off the engine, be sure to turn off the "charge" switch to prevent the battery from being discharged through the regulator.

[rcavictim]

Kelly,

Which engine did you get, a 185?  Have you checked it for sand?

[KellyR]

Thanks for the info.  I'm not a very good electrician, so the replies were helpful.  Too bad I can't just run the wire from the regulator without draining the battery.  I do have another switch I can use, though it will mean two switches rather than only one.  Guess I'll have to just remember to turn it on and shut it off.

I can't remember which model number the engine is.  It's been working great for me so far, except for little things like the switch.  I took it partially apart when I first got it and everything looked fine on the inside.  No sand what-so-ever.  I had been warned about that possibility

thanks again,
Kelly