blowing ground fuse when trying to start

[ruger1022]

I ave recently aquired a 1987 G2 Yamaha gas golf cart. The story goes that it was running when previous owner brought home but sat with no use for 2 years.I immediately went to get it running. Would not start. Started doing what I call normal checks. Fuel, spark,etc. Had fuel but no spark. Discovered that the ground fuse was blown. started checking electrical componants for shorts. While checking for shorts found several burned spots in wire. Got wire diagram and rewired whole cart. If I disconect the ground to the pick up behind the flywheel fuse does not blow but no spark either. Ohmed pickup nothing between any of the three wires.is the pickup bad or could it also relate to the ignitor

[TheNewGuy]

I can't help, but lets bump the thread back to the top.

[ruger1022]

Forgive my ignorance but I do not know what bump the thread back to the top means. new to forums of any kind. This forum seems to have some great content and have read all the threads that could relate to my problem but none quite like it. I have read mentions to removing the ground that goes throught the motors case but no direct reply to that problem. It is awsome to have a resource such as this

[crash12888]

If a post sits long enough it will get a lot of traffic on top of it sending it down the page, A friendly bump will get it back to top and more exposure.
One of the Yamaha guys will be along......

[worqhors]

Originally Posted by ruger1022

I ave recently aquired a 1987 G2 Yamaha gas golf cart. The story goes that it was running when previous owner brought home but sat with no use for 2 years.I immediately went to get it running. Would not start. Started doing what I call normal checks. Fuel, spark,etc. Had fuel but no spark. Discovered that the ground fuse was blown. started checking electrical componants for shorts. While checking for shorts found several burned spots in wire. Got wire diagram and rewired whole cart. If I disconect the ground to the pick up behind the flywheel fuse does not blow but no spark either. Ohmed pickup nothing between any of the three wires.is the pickup bad or could it also relate to the ignitor

The pulsar coil has only 2 wires, both connected to the igniter. Talking about ground, all your ground connections should be directly connected to battery negative or A1 starter gen.

[ruger1022]

the conector on the pulser coil mounted to the side of the flywheel has three wires one of which is a ground that goes under one of the two mounting screws for the pulser coil.
should I have an ohm value across the two coil wires. I am a master electrician by trade and know that i should not have continuity between the ground and the two coil wires, but seems as though I should have some kind of value across the coil. I have none. It is also confusing me why disconnecting this particular ground keeps the 10 amp buss fuse from blowing.

[sho305]

pickup coil
495-605 ohms at 68F
15V AC PEAK at cranking speed.
(white/red ~ white/black) wire code
Since I happen to have the manual open here.

You should test all the grounds, it is very common to have them not work on these and nothing is ground, the frame is not ground like a car and don't forget the entire engine is on a swingarm not the frame. If you put lights or something on them you have to wire to the battery or that fuse blows. If the main ground is not working like to starter, all kinds of things may not work. I think you might have two problems, something shorting and power issue to ignition or bad part. I would make sure you have good ground and then power to the Ignitor/coil/etc. and keep an eye on that fuse, figure out what is shorted. I think you can take the voltage reg out, its by the fuses and connects to the small wires from the generator, but not sure it would short something. I have no idea how the ignitor could draw 10A. There should be wiring diagram posted for this in stickies (posts at top of listing in this section).

Ignitor is expensive and rarely goes out, its a CDI more or less.

coil:
gap .43 inches/3,000 rpm
primary 3.57 ~ 4.83 ohms at 68F
(orange ~ red/white)
Secondary 11.2 ~ 15.2 K ohms at 68F
(high tension code ~ red/white)
Diode ~ No
Plug gap .028 ~ .031 in

[DOOmsman]

Yamaha chose to fuse the negative return to the battery for some strange reason.
Look for an over load of positive. Your an electrician its like plumbing
a gallon in, a gallon has to get out.

[ruger1022]

Thank you all for the advice. From the last two posts I am kind of getting that the one 14 gage ground wire from the battery is not enough to support the load of all the components. I think the pickup coil is bad because I get no value when testing between the white/red and white/black. After I downloaded the wire diagram and rewired exactly as diagram showed everything works correctly except for the pickup. When the key is turned on power to stop switch. depress gas peddal power to coil. Coil engages and generator starts rolling. No start. Ground fuse blown. replace fuse and disconnect ground to pick up. go thru starting process once more. All processes work the same but fuse does not blow. if there was a short in anything other than pickup fuse would still blow. but what is baffeling is if no continuity across coil (495-605 ohms) it should not short either. Unless because no continuity on pick up the ground is the path of least resistance for the voltage coming from the ignitor. I have done a search for a pickup coil for 87 g2 yamaha but have not found it can a newer cart pickup be substituted from say a g9 as it appears several parts seem to be interchangeable between these two models

[sho305]

Did you check the pickup for AC power on the starter? The pickup just triggers the ignitor, not sure why it would draw power unless it has the ignitor on all the time/etc and even then I don't think it would, but I'm no ignition guru. The ground fuse only runs the ignition and solenoid, that is all it does and all that takes power on the cart except the reverse buzzer. The starter/gen has its own big cable to start on and make sure that one has great connections.

You could try it with the coil off and pickup on, since without the pickup the ignitor should not be running the coil.

I'm not sure about them being the same, G2 and G9 are very similar but the ignitor is different for sure. The G2 has a rev limit and G9 does not, and the wiring is a little different to it. Most other things are the same.