I have an older 3W 60 single gas engine, I have run the engine a few times. I have mounted it on plane ready for running but can't seem to get fire to plug. This is the older module that requires 4.8 v. and I have insured that there is voltage going into the unit. Where, how, to trouble shoot this problem.

Some of the older ignitions had a problem with the cap breaking down inside......If you put a spark plug in the cap and use a starter on the engine you should see a spark...The caps with the problem were the very early ones with fiber inside VS the newer ones with molded silicone inside...
It's possible to take the cap off the wire to check for spark..If it still doesn't spark you need a new ignition..Not sure if they still supply older ignitions, the newer ones take a different sensor...
A new cap is about $20 from DA or 3W.....
If you need a new ignition I would suggest getting the whole thing from C&H, it might be cheaper and would certainly be better...

Thanks for the info. Good news is I got the cap disassemble and bad news is it still don't spark. Have C&H phone number ready to give them a call