1996 GTX grounding issue in front ebox

[bcritical]

First I want to thanks all the posters on this forum. I was able to find my issue but not the Root of the problem.

This is how I got there.

The ski would start right up but the rpms were erratic up and down and when rev it up the engine would shut off and gauges would go out and nothing would work not even the single press of start would do anything to gauges. I would mess with the lanyard until the gauges came back on. This happen 4 or 5 times..... then the gauges went out and wouldn't come back.

So I started checking all the fuses and grounds all looked fine. No ohm issues, no power issue, could crank the ski by bypassing the solenoid. I was kind of at a loss. THEN I read a post about a grounding issue in the front ebox so I tried what was posted and ran a ground straight from the battery to the ebox.
Wala all things came back and it started and ran fine no erratic rpm no shut down. Perfect. Then I disconnected the new ground to see if it would fail and the everything stayed on and started but the rpms were still erratic. While it was running poorly if I reconnected the new ground wire, perfect running engine, disconnect poor running. OK found the issue. But how to solve. Where is the ground coming from to the ebox.
After some research and looking through the wiring diagram it was clear that the ground came from the magneto plug. Checked that again and cleaned for good measure and all was good with ohms readings. Basically I know I have a ground issue but all points leading back to the battery show ohms at .5.

I know I could run a new ground from battery to ebox but I would have to buy something to run it into the ebox to make it water tight I see a few spare openings but I would rather fix the ground issue the correct way but can't find the failure.

Does anyone have any thoughts on what the root cause of the failure is so I can fix it instead of the band-aid of running a new ground?

Thanks

 

[Bills86e]

I have had to cut the ground cable lugs off and cut back the corroded cable end, solder & heat shrink tube seal the lugs back on, or replace the cable entirely.
The cable should be close to the starter for best spot. Electrical ground then goes thru block to stator, then G-wire goes to e-box ground lug, completeing/closeing the circuit.

 

[wfo speedracer]

Also the ground wire terminates at the stator, on the newer skis it is not attached to the stator , they just use a eyelet connector and ground to one of the front cover mounting bolts, I would try this first and see if it solves your issue.

 

[bcritical]

OK so I was checking all the grounds with my FLUKE and was getting great ohm readings. Then I decided to grab my light tester to see if maybe I had ground but not great ground. Put the light on positive side of the battery and started poking around.

engine anywhere--- dim light
e-box--- dim light
battery---- bright light
top starter bolt--- dim light
ground cable to engine as wfo speedracer suggested--- bright light.

So I then started removing the starter bolts and noticed it was not so tight, tighten it up 1/4 turn. Rechecked all the above checks came back bright lights everywhere. So I started to remove the bolt to make a better contact when doing so found that the starter was moving... that's strange checked for a bottom bolt...gone. Did some digging in the bilge and found it. Clean it up some.... put both bolts back in and everything is working perfectly.

I do have one last question though if the ground wire from battery is going to the front cover mounting plate not the starter bolts why didn't the ground work to the e-box. It seems like the bolts holding the front mounting plate to the block would be enough to make the e-box work and if the starter was not property tight then it would have issue with the ground for starting. Never had an issue starting. Seems strange. I am happy :thumbsup: it is working but I don't want another ground gremlin to find me later .

Thanks all

 

[wfo speedracer]

The ground wire from the battery is a high amperage wire mainly for the starter, everything else on the ski runs off the small ground wire but if the main ground wire isn't tight or is internally corroded then you don't have a good ground anywhere.