Ignition Issue - Weak / Sporatic Spark

[paulywog60]

I have a 1985 EZ-GO TRX (model A-1885) 2 cycle gas cart. When I ground the spark plug I get no spark or very intermittent spark. So I ground myself and crab hold the spark plug wire and notice the following: when the gas pedal is depressed, a very weak pulse - then nothing when running - then a very weak pulse when I release the gas peddle.
I have replaced the following ignition parts: Spark Plug & Wire, Starter Generator, Voltage Regulator, Igniter, Ignition Coil.
FYI - after I replaced the Starter Generator, the cart ran fine for about a week and then poorly for 3 days and then back to where we were originally...weak or no spark.
Might it be the Pulsar Coil and if so, where would it be on my cart??
Thanks for any and all input - Paul

[cart around]

Here is your manual. There is a troubleshooting section with electrical values at the end.

The pulsar is under the flywheel.


You should also study this thread. http://www.buggiesgonewild.com/gas-e...3pg-carts.html

[paulywog60]

cart around ~ thank you for your response and especially the owners manual which I now have printed and in a binder for future use
As to replacing parts prior to checking ~ I agree and can now do a better job of that with the manual. The starter generator I did take to an auto electrical shop prior to replacing and it was confirmed as bad. I surmise that is why the cart ran for about 10 days.
The link for the HEI mod would have been great a few weeks ago but I'm pretty committed to my current "stock" course. I just ran into this blog a little too late!!
Thanks again ~ Paul...

[Sean5545]

Hey just curious are you getting full voltage off the battery while running? Those coils can be fussy with an under voltage....

[paulywog60]

Just thought I would tie a bow on this thread and re-thank all who gave input and those who might read this with the same issues so...
** The problem with my weak/no spark in the final analysis was a balky wire going to the pulsar. This model engine has the 2 wires accessing the pulsar exiting the motor casing at about the 7 o'clock position behind a motor mount i.e. ~ very bad placement and impossible to see/check visually.
What did I learn?? (1) Check this wiring harness first!! I ended up trying to chase this problem down from the spark plug back and ended up replacing every part of my ignition system along the way ($$) when the problem was a broken wire at the other end ~ the wires exiting the grommet at the motor casing (2) The symptom remained the same, if you have a barley perceptible spark when you let off the accelerator pedal (you can feel when you ground yourself and complete the circuit at the coil but not see on spark plug) either your wiring harness to the pulsar is bad or you pulsar is shot). I know this because...(3) when doing your final test when you install your new wiring or pulsar unit, you must replace the flywheel cover (this not clear in the o/manual) as the sending unit to emit your new and improved spark in in the cover and not on the spindle where you might think. I got the same weak pulse until I reinstalled the flywheel cover. Thanks again and I hope someone finds this helpful ~ Paul