Duovac Wiring To Batteries

[BillandMarshaThompson]

We have a 1999 Beaver Patriot which has a duovac alternator.

I had the house batteries disconnected as I'm going to replace the transfer switch, while checking the push button shift selector as it was acting up I tried to start the engine and it had no response after putting the ground wire back on the house battery the engine would start as it always has this wire is apparently a ground wire directly from the alternator to the battery. I checked that wire after disconnecting it from the alternator for continuity to make sure it was the same wire as it is very hard to follow all the way from one end to the other.

My question is shouldn't that wire be going to the starting batteries?

[dickandlois]

Bill,

Welcome to the FMCA forum!

One would think that the Starter Ground would go there, But grounds are grounds and the coach and chassis grounds both connect to the chassis frame.

So if you connect the Engine / chassis batteries to the starter, that point in turn connects the engine that has a large ground Strap; in most cases that connects the starter to the chassis. There is often a separate(Smaller Gage)ground cable running between the alternators and the chassis / battery ground. This ensures a good ground for the charging circuit.

Alternators bolted directly to the engines should provide a ground point, but many engines have a large ground strap connected between the starter and the chassis frame to provide a good high current path when starting the engine.

One then has some extra ground connections between 2 points and a bad connection at any of them can limit current flow, the roundabout way uses less heavy gauge wire and saves some money.

Bottom line-- Save a buck where and when you can!

The result is the phrase, Check the Grounds / Check the Grounds. when something is not working the way it should first !

Uncle Sam says ground is ground the world around.

So if you had an issue with the transmission pad until you connected the engine battery ground to the Coach battery ground. Is there a bad ground connection or grounding strap somewhere?

You may never know, unless you try to find the ground point the shift pad did not see when wired the way you had it the first time.

Rich.