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Accidentally swapped battery terminals during install

G

geroms

New member
"I made a silly mistake while

"I made a silly mistake while reinstalling my battery this weekend. I mistakenly hooked up the positive cable to the negative battery terminal and visa versa. They only touched for an instant but it was long enough to generate a few sparks and make an evil hiss. Afterwards, all of the accessories still worked (stereo, trim, bilge pump, horn, etc.) however the engine will not start. Turning the key now does nothing. I can normally hear fuel pumping into the injectors when I turn the key to half on and my gauges come to life. None of this happens now... there's no clicking or anything, it is just completely dead.

I have a Merc 5.0 EFI 260hp. The boat is a 2004 Baja 202 Islander. I've checked everything I could think of: All fuses in fuse box, two fuses just past the ignition switch, two fuses just past positive battery terminal and the breaker switch on the back upper part of the engine. All look good. Anyone have any suggestions?"
 
"down on the starter ,where th

"down on the starter ,where the batt lead hooks up, is a fuse . it is square and has two wires on it. one orange the other is red. . replace this fuse. hope this helps."
 
"George;
When you turn the ke

"George;
When you turn the key to ON; do the gauges come to life?
If so, that does not sound like the 90 amp fuse on the starter solenoid that AK is suggesting, but I hope he is right.
If not, then likely it is that fuse. They are only a few bucks.

Rod"
 
"No, the gauges do not come to

"No, the gauges do not come to life. Nothing at all happens when I turn the key now. So that fuse could also control whether or not the gauges come on?"
 
"Yes, that most likely means t

"Yes, that most likely means the 90 amp fuse is toast, and that's very good news compared to all the other things that could have cooked.

Hopefully once you replace that you are back in business. It may be a bit of a bear to get to depending on how your doghouse is set up. It is right at the top front end of the starter solenoid, just below the stbd side exhaust manifold. It will have a heavy red and a heavy orange wire connected to it, and the other end of it is bolted to a large stud on the solenoid where the battery red cable connects.

NOTE: Suggest you draw a diagram or take a picture of how all is connected before you start ripping things apart!

Rod"
 
"If you find that fuse Rod is

"If you find that fuse Rod is talking about and it is a good fuse, it may be easier to pull the alternator and have it tested before going any further."
 
"I found the fuse and it was b

"I found the fuse and it was burned. And wow, what a fuse it is... never seen anything like it. I found it online and ordered a replacement. It appears to be the first thing in line coming from the battery positive so hopefully, nothing else got damaged. Thanks again all. Much appreciated."
 
"George;
That what it is ther

"George;
That what it is there for. To protect all the other much more expensive stuff down the line.
Hope it all works out for you.

Cheers,
Rod"
 
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