Polarity confused diesel pusher LY 35

[haverpen]

This is my first time post. I am repairing a 1995 LY 35 diesel pusher. The engine battery appears to have been installed with a positive ground. The coach batteries are installed with a negative ground. How can this be?

[roy sedgwick]

I am new to airstream, but have been in marine and automotive electronics for over thirty years, the brits used positive ground on some cars thirty years ago, but no more. as far as I know positive ground has not been used since. in addition there would be a problem since the coach's ground and the engines ground ( chassis ) are not seperated. double check the terminals, don't rely on the color of the cabels. Following the ground cable ( the cable coming from the negative terminal of the battery ) should be a short run to the engine block or chassis near the engine. If it is wired as a positive ground that cable would go to the starter on the engine. I can't imagine that there would't be adverse effects from a positive ground wire up on your MO

[roy sedgwick]

my first time for reply messed up. check your original intro. my reply should be there.

[haverpen]

Reply to Roy. Thank you for your insightful response to my confusion. What appeared to be a terminal of ground cables was really a junction of 4 positive cables: from the battery, from the auxilliary start solonoid, from the starter, and from the generator. All 4 are red. Thanks from haverpen@comcast.net, full name Larry Koppenhaver.