Charging System Problem…...
 

Hello All,
I am a new member of the Mariah Owners Club and Mariah owner for 19 years.
I own a 1995 Z235 7.4L Carb. Bravo1. Purchased new from Willow Cove Marine on Greenwood Lake N.Y.

I am experiencing a problem with my charging system. The dash mounted volt gauge shows @ 13 to 13.5 volts at Idle. As I increase rpm's the voltage drops to @10 volts. From @ 2000 rpm to WOT the voltage stays at 10 volts. When a separate gauge is hooked up to the posts of the dash gauge the readings are the same.

Using a separate gauge the voltage shows between 13.5 & 14 volts at the alternator discharge (orange wire) and at both batteries. The same is also found at the power distribution block in the engine compartment & behind a panel at the drivers position. The voltage does not drop as the rpm's increase on this gauge.

I have checked for loose or corroded connections with negative results.

The batteries are new and fully charged.

Thanks for reading,
any help would be greatly appreciated
Tim

Re: Charging System Problem…...
 

Hi Tim,
Welcome to the club and nice to hear from a fellow Hudson Valley Mariah owner.
To help isolate your problem I would start by obtaining a couple of lengths of wire. Connect one end of the first wire to the negative post of the battery. Connect one end of the second wire to the negative terminal of your voltmeter in the dash. Connect a separate voltmeter between the remaining ends of the two wires you just hooked up. You should see very little voltage between the two wires. Rev your motor and monitor the separate voltmeter. If you see any substantial voltage variation (like 3 Volts) then you have an issue with your ground wire to the dash. Follow the neg wire from the voltmeter in the dash and move the location of the neg wire from the Voltmeter behind the dash to the next connection and so on all while using the battery neg terminal as a reference to find your bad connection. If you see no substantial voltage variation then move the wire ends from the negative terminals of the battery and voltmeter in the dash to the positive terminals and repeat the test. If you see voltage variation here then you have an issue with your positive wire. My guess is you have a ground issue.
Good Luck,
Steve

Re: Charging System Problem…...
 

Thank you Steve.
Hopefully the rain holds off tomorrow afternoon and I can try your suggestion. Sounds like a good plan. I'll let you know how I make out.
Tim

Re: Charging System Problem…...
 

Hey Steve,
If you could see the smile I'm wearing. Thank you so much for your response to my post.
Only had a little bit of time today so I ran a ground from the battery to the Dash volt gauge.
The gauge shows charging like a champ……idle through WOT. When I have more time during the week I will check in depth as to where the bad ground is and fix same correctly.

Thanks again,
Tim

_____________________
1995 Mariah Z235 Davanti