Chester Copperpot
Cadet
- Joined
- Sep 7, 2016
- Messages
- 6
I tried the best I could to find an answer without starting a new thread, but I could not find what I was looking for.
I just picked up my first boat. 1983 Sea Ray 225 Cuddy Cruiser. 260 Merc with the "pre" Alpha outdrive ....S/N 627XXXX. The boat had newer batteries in it, but they were dead. I replaced them with brand new batteries. Took it out for my first cruise, and my voltmeter wasn't looking good (soon to replace with one with actual NUMBERS rather than green/red). I noticed it was this way before takeoff. Checked batteries with a multimeter, showed 12.2volts or so on both. Everything ran OK electrical wise ( but I found out that I have the dreaded shift interrupt - cable issue). During the cruise, we used battery #1 (I have a battery selector switch)
Anyways, after we got back home, I put my multimeter on the back of the in dash voltmeter to see what my actual numbers were. Battery #1 was 12.00 volts. Battery #2 was 12.2 volts. I started the engine (on muffs) and the voltage did not change. I turned the engine off. Tested voltage right at the batteries. Voltage was around the same as pre-cruise numbers but #2 was higher than #1 now. I didn't write them down this time but #2 was higher again...... Started the engine....no change.
Since it looks to be an aftermarket cheapie alternator, I figured it was bad, so I disconnected the orange wire at the alternator. Started engine.....put the + lead of my multimeter on the alternator positive terminal and grounded the - lead on a battery negative terminal. It showed 121 volts DC...NOT 12.1, it was 121. Kinda freaked out at that. Turned off the engine. Put the + lead of the multimeter back on the alternator positive terminal and I could watch the voltage bleed back down to zero.
Then I checked for continuity from the alternator end of the orange wire to the other end of the orange wire where it is also connected directly to the red/purple wire at the 90 amp fuse and I had continuity so I knew the alternator cable was good. Then I checked for continuity from the alternator end of the orange wire to the main battery cable connection at the starter (which is the other side of the 90 amp fuse) and I didn't have continuity. To me that means there's no continuity through the fuse.
So, my thinking.....alternator went bad and threw out an overvoltage and also fried the fuse. But my question is, if the fuse was bad, why does everything in my dash work, the engine runs, etc etc?
Am I wrong in my assumption? If the 90 amp fuse is bad, could you still have power at the dash and the rest of the boat? I ran out of time but tomorrow I hope to completely remove the fuse to test it for continuity sitting by itself.
THANKS IN ADVANCE!!
I just picked up my first boat. 1983 Sea Ray 225 Cuddy Cruiser. 260 Merc with the "pre" Alpha outdrive ....S/N 627XXXX. The boat had newer batteries in it, but they were dead. I replaced them with brand new batteries. Took it out for my first cruise, and my voltmeter wasn't looking good (soon to replace with one with actual NUMBERS rather than green/red). I noticed it was this way before takeoff. Checked batteries with a multimeter, showed 12.2volts or so on both. Everything ran OK electrical wise ( but I found out that I have the dreaded shift interrupt - cable issue). During the cruise, we used battery #1 (I have a battery selector switch)
Anyways, after we got back home, I put my multimeter on the back of the in dash voltmeter to see what my actual numbers were. Battery #1 was 12.00 volts. Battery #2 was 12.2 volts. I started the engine (on muffs) and the voltage did not change. I turned the engine off. Tested voltage right at the batteries. Voltage was around the same as pre-cruise numbers but #2 was higher than #1 now. I didn't write them down this time but #2 was higher again...... Started the engine....no change.
Since it looks to be an aftermarket cheapie alternator, I figured it was bad, so I disconnected the orange wire at the alternator. Started engine.....put the + lead of my multimeter on the alternator positive terminal and grounded the - lead on a battery negative terminal. It showed 121 volts DC...NOT 12.1, it was 121. Kinda freaked out at that. Turned off the engine. Put the + lead of the multimeter back on the alternator positive terminal and I could watch the voltage bleed back down to zero.
Then I checked for continuity from the alternator end of the orange wire to the other end of the orange wire where it is also connected directly to the red/purple wire at the 90 amp fuse and I had continuity so I knew the alternator cable was good. Then I checked for continuity from the alternator end of the orange wire to the main battery cable connection at the starter (which is the other side of the 90 amp fuse) and I didn't have continuity. To me that means there's no continuity through the fuse.
So, my thinking.....alternator went bad and threw out an overvoltage and also fried the fuse. But my question is, if the fuse was bad, why does everything in my dash work, the engine runs, etc etc?
Am I wrong in my assumption? If the 90 amp fuse is bad, could you still have power at the dash and the rest of the boat? I ran out of time but tomorrow I hope to completely remove the fuse to test it for continuity sitting by itself.
THANKS IN ADVANCE!!
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