What wire did I mess up?

[GJarrett]

2009 5.0MPI in a '99 240 Sundancer. I believe the original engine was a 5.7

While working in my bilge, I heard an electrical arcing noise and saw that I had stepped on a red wire on the port side bilge floor that I had evidently pulled out from somewhere while stepping on it. The wire was very hot so it had either just been pulled out, or my foot had moved it to a ground and shorted it. The other end of the wire goes directly to my battery switch and is connected to the same terminal that the wire that goes directly to the starter. I cannot find anywhere on the port side of the engine or other electrical items there that this wire might go to.

The first photo shows the wire connected directly to the battery switch, and the second shows its position laying on the bilge floor just to the port side of the engine. Can anyone tell me what this wire is and where it is supposed to connect?

 

[Quint4]

I will guess bilge pump, although it looks a bit large.

Perhaps a stereo power amp?......if so, I would expect a fuse near the battery switch.

 

[Creekwood]

Not bilge pump. they should be brown. Its a DIY add on for something non OEM.

 

[SCORPIO]

What accessory doesn't work now? That will tell you where it went.

 

[Mike Blake]

Can you follow the wire? Or does it hide? LOL

 

[Nehalennia]

Look at your starter.

 

[rpasquarello]

I will guess bilge pump, although it looks a bit large.

Perhaps a stereo power amp?......if so, I would expect a fuse near the battery switch.

My vote is for an add-on or replaced bilge pump.

 

[Happy Hour IV]

battery wire to alternator. if so starting engine could burn out alternator if not connected

 

[rpasquarello]

battery wire to alternator. if so starting engine could burn out alternator if not connected

If you are correct, he should easily find the other terminal end still connected on the alternator where it pulled out.

 

[GJarrett]

Thanks - alternator will be the first place I look. I could have easily missed that - looking upside down while twisted around in there leaves plenty of possibility for not finding something obvious

The bilge pump was the first thing I thought of, but then it occurred to me that it should always be hot, right? Since it is connected to the same terminal as the starter cable I assume that turning the battery switch to the "off" position would turn it off too.

BTW, there's no powered subwoofers or aftermarket stuff on the boat that I am aware of. It does look like some sort of aftermarket add on wire, though.

 

[SCORPIO]

A volt meter will tell you if the wire is hot or not. I'd check it to be certain it isn't sitting in the bilge live waiting to make a spark. Look at the alternator for orphaned terminals and also look around the engine for sensors etc that have a terminal but no wire. Also look at the starter solenoid where the main battery cable and other wires connect. Since you heard an arcing sound, the wire was hot when it came apart and what ever it was attached to must have been 'hot' at the time otherwise it would not have arced.

 

[AFD]

how did you make out? any luck finding the empty terminal?

 

[GJarrett]

Nope. I cannot find anything at all to plug that in to. I do have another idea. My other Sundancer had an engine alarm that went off if I left the key on too long without starting the engine. I seem to recall when I bought this one a year ago that I heard it work once, but it never did again. I don't have any sort of engine alarm on this boat. I wonder if it could go to some sort of alarm? If so, where would that be? And while we are at it, what was that alarm for anyway?

 

[Bt Doctur]

a second bilge pump , a high water bilge switch, or powers a oil pressure fuel pump switch.???????????????

 

[rpasquarello]

a second bilge pump , a high water bilge switch, or powers a oil pressure fuel pump switch.???????????????

Hmmmm....let's follow that train of thought.

Look for a couple of screw holes down in the bilge where a pump or switch may have been been at one time. Chances are that they were not filled back in.

 

[SCORPIO]

Most engine alarms are triggered by low oil pressure or high temp. I'd guess low oil pressure would be the most likely.

 

[AFD]

well i would use a piece of string the same length and make an arc to see where it could have come from and look EVERYWHERE that it could have come from .

 

[2000SEARAY280SS]

Are you sure the two pictures show the same wire? From the pictures they look to be different sizes.

My battery charger has wires about the size of the bilge wire that go directly to the batteries.

i also have a small gauge wire going to the mercathode module from the battery switch area but it is on the powered side of the switch not the common.

It's not a power trim wire is it?

 

[GJarrett]

Well it's raining a flood here now and I've got a huge honeydoo list besides the boat, so it will be next weekend before I can continue the investigation. It is the same wire; the photo at the battery switch was taken a lot closer than the one in the bilge. I'll try the suggestions here and report back later what happened. I did try to find EVERYWHERE that wire could reach, but need to give that a second try in better lighting and more time to methodically check it out. Currently I am thinking along two possibilities....

Firstly, I did find a green wire with a "Mercathode" label in the bilge but this boat does not have a Mercathode anode thingy on the outdrive. Since it has had an engine swap I assume it may have originally had a Mercathode system but it was never replaced during the swap (?). I don't know a thing about Mercathode system except it should have the anode unit thingy on the outdrive - what would it have had in the bilge, and could this wire have been a Mercathode wire of some sort? I cannot track the green wire because it goes somewhere under the engine to a place I could not find without pulling the engine out. Maybe this wire went to a terminal that the green wire goes to under the engine?...

Secondly, I had mentioned the engine alarm in a prior post. Yesterday I drained my oil for a oil change so I warmed the engine up for a few minutes to thin the oil out before sucking it up the dipstick tube. The engine alarm that I thought I did not have went off and stayed on, beeping once every second the whole time. I checked the oil gauge which was showing 40-60psi so I know I had oil pressure. I wonder if that wire went to a terminal at the oil sensor on the engine? I am confused since the gauge was showing pressure, but the alarm was going off. Where would the oil sensor be on this engine (5.0 MPI)?

 

[SCORPIO]

The oil sensor would most likely be screwed into an oil gallery hole in the lower part of the block. Could be back by the oil filter head or somewhere else. It would most likely be low on the engine rather than in the heads. If that alarm has never gone off before but is now constant, I think you're on the right track. There is probablly a sender with a terminal on it with no wire attached just waiting for you to find it. Good luck and report back what you find.