Weak Spark; Coil - No Sec winding

[ksmechwannab]

Hello BGW: I am really at my wits end with intermittent/weak spark dilemma on an old 83 EZGO 3pg Marathon 2 stroke, and really need some expert knowledge on ye ole stock OEM IGN coil with green & orange wire because I am pretty sure I just received two new coils from the supply folks with no secondary winding - no ohms (open).

According to 85-86 repair manual, it says I should have (blank) ohms value on secondary winding (orange wire to spark plug wire)... sorry manual is not at my finger tips. Most everything I've read about coils shows the primary & secondary tied together internally.
Coils have good ohms values between green and orange wire (or blue & red), but weak spark. Thus my spark plug is wet with fuel and smokes like crazy when I try to start the ole girl.

Your thoughts/knowledge and experience regarding having both primary & secondary winding would be very much appreciated?

I've read about the HEI mod and wonder if others have had the same issue with new coils not working, noting the new OEM coil has changed to blue & red wires on the IGN coil (PN 5121). I called Nivel and they said they sell the same coil; probably others too.

As I understand the manual, both should be present. I just wonder if the parts world is aware they are selling crap from overseas. I would think if the manual says it should be there... I suspect there is a good reason. Must be there's no vendor QA/QC because they don't know what the specs are supposed to be.

I do plan to install the HEI mod eventually, just hope the auto coil is good; already have the GM ignitor module to replace factory ignitor. Maybe this is why Auto Zone & BU allows returns on electronic parts; hum?

Anyone have or know a tech contact at EZGO? Tried their website, but have not received a reply.

P.S. The engine has been rebuilt to include new seals, crank, bearings, piston, etc. Engine seems sound with S/G turning her over, but getting the ignition to bring her to life has been my issue. Carb cleaned x3 (or 4 - C.R.S.)

THANKS for any support - at it for 2 months on & off nights & wknds, not much hair left to pull.

[cart around]

Are you changing the setting on your meter?
Orange to green resistance should be 3.6 ohms to 3.8 ohms.

Orange to plug wire should be 11.5K ohms to 12.5 K ohms. 12,000 ohms is a lot. If you don't change the meter, it will read open.

Did you open the fuel pump, and check the lower diaphragm for rips? That will cause a wet plug with a weak spark.

How much does it actually run?
Did you double check that the piston has the hole facing the intake when you put it together?

An 83 is a 2pg.

[ksmechwannab]

Hello Cart Around: my bad on the coil check, original OEM coil is good, bad igniter coil. I had spark with new OEM igniter and old OEM IGN coil last night (appears weak to me), just not enough umf to get the cart to come to life.
Tonight, I have since tried a cylinder type Master Pro IGN coil (PN 2-5195) in conjunction with the HEI ignition module (DR100 auto zone), but... still no spark yet. Something is awry.
Meter set at 200k I get 097k across secondary, and 200 ohm range I get 017 ohms across primary. Not sure if the two components are compatible, so I'll get the autozone ignition coil (C839) that someone recommended to use with the DR100 IGN module for a 94 Mustang.

I'll also try to find a copper core spark plug wire someone recommended as well since I've been trying a regular auto carbon ignition wire. I tried holding the regular copper spark plug wire inside the coil, but I'm not sure I was making good contact, while holding the plug to ground. Hopefully NAPA can make one, I check O'Reilly today and no luck.

No, I did not open the fuel pump yet, tonight I looped the lines to recirculate the flow through the pump to see if I might lose capacity/volume while I was cranking it over looking for spark - no leak detected yet - fuel seems to be at the same level when I started, I can see through the fuel filters.
I'm afraid I might break a good seal on the gasket and o-ring. Don't need any more problems with this darn cart if I can avoid it. I ordered one today just in case - can always us it for testing.

Oh yes, I checked the piston (after jacking it up and crawling underneath to remove exhaust pipe) - she's good!

I have 160 compression as of tonight, and since I've been cranking without spark plug installed seems excess fuel has gone out the cylinder. I gotta get my spark right first and then I'll tackle the fuel - I think with the compression I'm getting I'll need a real good spark. She was pegging out around 180, but once I stopped cranking it settled at 150-160 (WOW!). 40:1 mix for new piston break-in - she's well lubed internally!

Using my test light tonight I have voltage on the + & - side of the coil, same for the HEI igniter module on C & B, so I know it's getting voltage to the coil - brand new battery. Pulsar still ohms out at 152 ohms. I did replace it with a new one, and maybe got it out of alignment/wack. I'll check timing again tomorrow. I did not remove timing adjusting plate, and thought the pulsar would go right back into place.

Thanks for your input - I'll keep hammering away until I figure this thing out, or I have a heart attach and die. It's become my quest to see this thing run; got too much time and $$$ invested to stop.
So far she's only managed to crank enough to produce a smoke stack, and spin the wheels, but not enough to really run like it should. Like a fast idle, but that's with wheels off the ground.

[cart around]

The best compression you should see is 120.

When I did my conversion, I used a $15 round coil from amazon. It runs great, but I also think it was a waste of time. My problem was a ripped diaphragm the whole time.

Read this for future reference. http://www.buggiesgonewild.com/gas-e...fuel-pump.html

[ksmechwannab]

Thanks CA - I'll definitely keep this in mind. I went ahead an ordered one, and a carb just in case, can always use it down the road.

Yes, I wonder what's going on with that compression with STD piston. It started out with 140, and has since increased, hopefully not a seal or gasket leak!?

I still wanna complete my HEI mod and hopefully never worry about another expensive OEM igniter module or factory coil going bad - if I can just get that darn HEI module to produce some spark.

I found out it's not as easy locating just one or two copper core plug wires as I thought it would be. Harley had them but name brand and so they're quite expensive just for one wire. Lawnmower shop was closed by the time I got there, but I found some tractor copper plug wires (set) for a decent price on the internet.

Keep your rod rollin and thanks again for you help - Cheers! Steve

[Spicyunicorn]

Had one with intermittent spark and the wire connected to the micro switch was hanging on by two strands

[ksmechwannab]

Thanks! I've overlooked switches just because it starts/cranks. Disconnected the reverse busser sw early on, but the ole kill/peddle sw is still active - I'll be sure to check it; can't hurt!

A friend of mine has one wire from the pulsar going straight to ign coil and it start and it starts & runs (I'm soo jealous) - I'd surely like to see whats behind that flywheel. HEI mod seems simple enough, but... I think this cart might be poozzest'd - like Louisiana voodoo

[ksmechwannab]

Back to the ole drawing board I sure hope its a bad NIB HEI igniter module DR100. I've tried two different style IGN coils, new spark plug & wire, new pickup/pulsar coil, and new solenoid just to rule out the original (good thing I had a couple of spare items around the shop!). I also slaved in a new V/R early on but no luck there either

And, no luck on the micro sw either; it checked good - didn't think it was bad but hey didn't have anything to lose checking.

As per other treads in HEI mod - I check AC volts coming from the pulsar and it pegged at 5.0 (highest) with voltmeter set at 20 vac if this helps anyone down the road. 2.5 seemed to be the lowest, I think it has to do with crank & S/G speed.

Can't wait to see if the another new module might work; good thing they're in-expensive or cheap enough to try!

I've found an illustration on WWW that shows an internal NPN transistor inside the DR100 HEI igniter module, and wonder if there's anyway to test output signal going to the IGN coil? Although if the internal signal converter isn't converting (uuurgh)... - good thing AutoZone allows returns on electronic parts!!!

Charlie-Mike

[ksmechwannab]

Good news! It was the (new in box) HEI igniter module. I went to AZ pick up another HEI igniter DR100 today and installed it tonight - I HAVE SPARK; YIPPEE!!! And it worked with a regular cone type ignition coil. Good thing these HEI components are affordable!!!