Engine Electrical Issue??

[flatlndr]

Hi all,
Was out tinkering on the old '82 CrossCountry today. Thought I would clean up
the frame ground on the neg. engine battery cable. Noticed when I was loosening it, it
threw some sparks????. I expect this when I disconnect the + cable but not the
neg. Since I'm not sure I understand all the wiring on a MH, don't know what good or bad.

With both ends of the - cable disconnected, I put my old analog meter between the
neg. batt. post and the frame ground post and got about 12v?????. But when
checking between coach batt. neg. post and frame ground, got 0 reading.

Do I have a short to frame ground somewhere, a bad battery, or normal(which i
find hard to believe).
As a side note, I believe I have an electrical issue, as I have two other
problems.
1 - fuel gauge is pegged at FULL, both tanks, never moves(from what I've read probably bad ground wire on tank), and
2.intermittent problem with engine not shutting off when the key switch is
turned off.
I hate electrical issues.
Anyone know what might be up for sure??
Thanks

 

[Just Lou]

Depending on how big those"sparks" were, I don't see a problem with anything you observed.

I suspect (actually expect), that if you removed the ground cable between the coach battery and frame ground, and repeated the measurement as you did on the chassis/engine battery, that you would also see 12v.

I don't immediately see a connection to the other electrical problems you mentioned.

The ignition (not shutting off) could be a defective ignition/key switch or an ignition relay hanging up.  I guess I should ask if this is a diesel or gas engine before guessing at this problem solution.

I would remove the wires from the fuel gauge and observe any movement before looking deeper.

 

[flatlndr]

Thanks Lou.
This thing is a little more complex than my old Ferguson tractors. Everything is working fine other than switch and gauge. Just hadn't noticed
the small sparks before.
Will continue to work on the other problems.
Thanks again