Batteries not Charging I Need Help!
 

Put the boat in the water for the first time. Everything ran well except that I noticed the batteries where not charging putting an early end to our day, barely making it back to the dock limping in on one engine after the other shut off.

I have twn batteries, one for each engine running to one four position switch. Neither volt gauge showed a charge and both alt's where new last season. These engines where in another boat last season and just installed into this boat.

I have a pair of new batteries that I will install this weekend so that I can run the engines to check the alt's, I am not familiar with how the wiring should be to get a charge back into the batteries. I have Delco alt's with a pos+ threaded terminal and a 2 wire plug. Can someone send me a wiring diagram for a mercruiser system showing me where the alt wires should be going? I also have another switch to install and would like to add an aditional battery for each engine. Long story short I want to have 2 switches with 2 batteries on each switch and need to know how to wire the alt's to charge the batteries and thru a volt gauge. Help Me Please!

Check your PMs I sent you one.:party-smiley-004:

I was playing around and found this, But I'm not sure if this is what you where looking for? Did the other place help you out yet just wondering.http://forums.iboats.com/showthread.php?t=158077

Thanks for the reply. I will be looking at it this weekend and putting in 2 switches instead of 1 and installing 2 more batteries. I'll pull 1 alt and have it tested. Who knows maybe they crapped out over the winter? Doubt it though. Most likely I have a bad ground someplace for the wiring harness? I'll post my results and diagram when I'm finished. These will help, thanks again!

I had an issue were my keys messed up and I was not getting power to the field wire. I will see if I can find out what wire is what. One is battery voltage I think and the other is the field wire in the two prong plug.

ok hope this helps. Found it easier then I thought.

From looking at the wireing diagram the purple is your key power. This NEEDS to have power to start the alternator charging. Test this first. The Red or red and purple needs to have power all the time. This is what tells the alternator what voltage the system is at and how hard it has to work. Black goes to ground and the larger one needs power back to the starter and then to the battereies. If you are going to run 4 batteries then you will NEED an isolator.

Thanks guys, hopefully I can get a chance to look at it tomorrow. I'll throw a set of new batteries in it so I can run it and start probing around with the tester. I knew I could get some answers here.