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View Full Version : Electrical experts: what is wrong with this?



Bob Weisner
05-24-2006, 2:28 PM
It took most of the day to get my boat across the ice and into open water. I hook up the battery and all I get is a whirring noise, then nothing. Try it again with the same result. I figure the battery is low so I pack it back up the hill, dig out the generator, locate the battery charger and hook it up. The meter jumps all the way to the top...15 amps. I leave it for an hour and its still at 15,

I pack it down to the boat and repeat the procedure. Nothing. I check the in-line fuse and find it is blown. Replace the fuse and it blows as soon as I hit the start button. Replace the fuse again. So I remove the starter and disassemble it. I douche it out with Brake Kleen. My thought is that some of that dust from the brushes is arcing to the case and shorting everything out.

I decide to take my voltmeter down and check continuity on all the wiring. Voltmeter won't work. I disassemble it and find a blown fuse. I don't have a replacement. I wrap the fuse in aluminum foil and the thing works. I check the wires and all are good.

Back up at the cabin, (which is a heck of a hike from the boat for an old guy) I hook the starter to the battery charger. It works fine.

I take it down to the boat and lay it on the bottm of the boat and hook it directly to the battery. It runs backwards. I reverse the polarity of the connections and it works correctly. I install it on the engine and hook up the battery BACKWARDS and the engine fires right up. So I now have the negative cable going to the hot post on the starter and the positive to ground.

The only thing I can figure is that the battery somehow changed polarity while connected to my solar panel all winter. I can see no other explanation. Hopefully some of you will have had a similar experience or ideas.

Mike Henderson
05-24-2006, 2:40 PM
I don't think that a lead-acid battery will hold a charge in backwards polarity. You might get a small amount of current out of it (backwards) but the voltage would fall fairly fast. At least that's my experience with hooking up a lead-acid battery in reverse.

But batteries are marked + and - so you should be able to check the polarity with a volt-meter to see if the battery is charged backwards.

Long time ago, on a six volt VW with a generator (not an alternator), I had a dead battery and jumped it backwards. I was able to start the motor but the generator was charging reverse polarity. When I stopped the car, it had a dead battery. When I jumped it properly, I was able to start the car and the battery charged. No permanent damage.

Mike

Tom Jones III
05-24-2006, 2:54 PM
Wait a minute, forget the battery where are you that you have to push your boat across ice at the end of May. Second, why would you live there? I went for a run today and it was 92* outside. I have had 52 ounces to drink and I'm still a little low.

Marty Walsh
05-24-2006, 3:12 PM
Wait a minute, forget the battery where are you that you have to push your boat across ice at the end of May. Second, why would you live there? I went for a run today and it was 92* outside. I have had 52 ounces to drink and I'm still a little low.

Tom,

You beat me to it! I'm taking a break from doing the site work on my new shop, and I'm dripping sweat! It's 91* here...

Ice in May? Boating in ice? I think that might be part of the problem! :eek:

Sorry I can't offer any assistance with the actual problem, Bob. Good luck.

- Marty -

Frank Fusco
05-24-2006, 3:36 PM
I don't know why I even read this post. I need two Boy Scouts just to help me change flashlight batteries. I'm going to help you? Well, yes. Move to Arkansas, no ice. It's in the 90's today.

Cliff Rohrabacher
05-24-2006, 3:42 PM
It took most of the day to get my boat across the ice and into open water. [...]
I'm with Tom here.

I have applied the most sophisticated technology to the issues presented in your post and concluded that
1.) your equipment is angry with you for making it freeze it's butt off.
2.) you need to move to a place where they only have ice occasionally and preferably only in the drinks.

Other than that you may have a reverse polarity fairy sneaking around at night.

Jeff DeVore
05-24-2006, 3:55 PM
Are you sure you did'nt put the fuse in backwards?:D :) :p

Bob Weisner
05-24-2006, 4:47 PM
I don't live there!:D It was from a friend up in central Alaska that had asked the question. He lives in a small town that is about 40 miles off of the road system.

Tyler Howell
05-24-2006, 8:20 PM
Cells of the battery sound shorted. Time to replace.