Replacement Alternator Wiring
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=48650
Printed Date: October-06-2024 at 12:25am
Topic: Replacement Alternator Wiring
Posted By: Tofasttoocare
Subject: Replacement Alternator Wiring
Date Posted: May-05-2020 at 9:54pm
|
I am replacing the alternator in my boat (see information in signature). I bought a new Mando alternator and wired it according to a diagram I found online (see picture below). The wiring on my old alternator is below as well. The problem I am having is when I engage the starter the main 50A breaker pops and there is no power. After about 10 mins it closes and I have power again. In an effort to diagnose the improperly connected wire, I disconnected the wires one at a time. Each time with any one of the wires disconnected the breaker would pop. I also tried disconnecting two wires. I tried all of the combinations and it still popped. Last I disconnected all of the wires and it still popped. To check that I hadn't messed anything up, I reinstalled the old alternator. Everything worked fine. I am not sure what the problem could be. Any insight would be appreciated. Thank you.   ------------- 1996 SNOB 350 Chevy Pro Ski TBI PCM 1.23:1 |
Replies:
Posted By: Jonny Quest
Date Posted: May-06-2020 at 1:51am
The wiring diagram below might shed some light on your situation. JQ ------------- Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum |
Posted By: KENO
Date Posted: May-06-2020 at 9:19pm
|
TFTC I think the only way that makes any sense is : the big orange wire hooked to the output terminal The green wire is excitation and would go to the excitation terminal on the new one Black wire is ground. The sensing wire that you don't have on the old Prestolite could be a short jumper from the sensing terminal to the output terminal that the orange wire is hooked to or if you have a lot of loads run the wire from the sensing terminal back to the other end of the orange wire where it hooks to the main breaker for a little better sensing of system voltage. Either way works. And this is just me thinking, since I don't have a Mando sitting in front of me 
|
Posted By: Tofasttoocare
Date Posted: May-09-2020 at 1:24pm
|
Thank you for the responses. I am wondering what the difference is between the S terminal and the EXC terminal. They are very plainly marked on the alternator, but I am wondering if they have a similar function the EXC wire from the old alternator needs to go on the S wire for the new alternator. Thank you  ------------- 1996 SNOB 350 Chevy Pro Ski TBI PCM 1.23:1 |
Posted By: KENO
Date Posted: May-09-2020 at 1:59pm
|
TFTC The Green excitation wire from your harness would go to the excitation terminal on your Mando. The Orange wire from the harness goes to the output terminal on the Mando. In an earlier post in this thread I mentioned a jumper between the sensing terminal and the output terminal In your picture of the Mando, that jumper is already installed from the factory it's that flat strip covered by a piece of insulating sleeve. Leave that the way it is and just hook up the 2 wires as mentioned above and you should be good. You don't want to hook the excitation wire to anything but the excitation terminal It gives the alternator the kick in the butt that it needs to start making some electricity. If it doesn't work like that you have other problems, which may be the case since it looks like you've replaced multiple alternators when looking at your old posts. |