G16 Keeps blowing 10A fuse randomly.

[Rob_C]

Hi,

I'm looking at a completely stock G16 that keeps blowing the 10A ground fuse, no accessories fitted. I can't see anywhere in the harness that is chafed or chewed u. All the plugs and terminals I can find are clean and tight.

The cart starts and runs fine with the fuse blown but will not charge. Replace the fuse, it does everything as it should until it blows the next time and the battery goes flat making it run rough before not cranking.

I have not been able to determine exactly at what point the fuse blows, it's inconsistent.

Cheers,
Rob

[rstacy]

I have had two things do this.
If the braid on one of the starter brushes contacts the side of the end cap it will intermittently blow the fuse.

I have had the wires in the harness make contact at the back of the floorboard where it turns up towards the battery. It tends to rub on the frame at this point.

You do have a wiring issue. The engine should never start with a blown fuse. That fuse is the first thing in line and supplies power to the solenoid.

Just a comment. A low battery wont make the engine run rough. It will certainly make it slow to start but the engine doesn't use the battery for spark or fuel.

[Rob_C]

Thanks rstacy,

I did check the harness specifically where you mentioned for the same reason but there's not even chafing on the plastic conduit there. I''ll split it and check it just the same.

I hadn't pulled the starter but will do now, that's a good tip, thanks.

I did look at the wiring diagram and thought the same but there are numerous posts of the same condition on the forum here which had me second guessing myself. If there's a stray earth somewhere, it's a pretty decent one. I was aware of the fuse providing the only electrical earth for the harness but after trying all I could think of, you start to clutch at straws.

You're obviously correct on the ignition, I wasn't thinking there but oddly, it does seem to run rougher once the fuse is blown. Given it's not charging at that point, the starter generator shouldn't be applying added load so I'm unsure what the deal is there.

I'll let you know how I go.

Cheers,
Rob

[Rob_C]

Got it out and apart,

The braids all appeared to be well clear of the case and other wiring but there's been a lot of moisture inside it at some point along with a fair bit of carbon from well worn brushes. I don't see the carbon and aluminium corrosion being an intermittent fault but I can not find anything else that may be the cause.

I'll give it a good clean this morning, install new brushes, refit and see how it goes.

Cheers,
Rob

[Rob_C]

I did find an issue on clean up. Seems the field winding core and the armature laminations have been making friends, possibly bearing failure in the past given the surface rust on the armamture in that area.

I believe this is a mechanical not an electrical issue though given both should be insulated?

Bonus pic of the brush holder post cleanup. I'd have liked it to be cleaner.

[rstacy]

Overall that starter looks great. I agree that the scraping is an issue probably caused by a bearing in the past. The corrosion is usually a result of putting the rubber caps on in the wrong position There is one cap with a drain. That one goes on the bottom.

This is a really interesting problem. The fuse blows so it must be doing something yet the cart still runs after the fuse is blown. That is very strange. You have something that is not one of the run of the mill issues.
There is one other spot to check on the harness.
Under the floor board where the wiring harness goes up the kick panel towards the dash, that bend is a problem spot. You have to open the plastic and look at the wires. I know its strange but I have had wire damage with no visible damage to the plastic conduit.