2002 BF50 Not charging ?

[MarkCaf]

Hello,

I'm new to the Forum and have a few questions (need help) after recently making some repairs.

It all started with the motor acutely misfiring while on the water after about 20 min. (Mixed; idle, Troll, WOT)

My first suspicion was a fuel/carb issue. So I did the following :

Complete carb. tear down including gaskets, New Racor, New priming bulb, Tank pumped, New fuel filter, New plugs, New fuel pump, New thermo., New Battery

After it still mis-firing a new CDI was installed which fixed the problem.

Then...while on the water, I noticed the idle RPM jumped from 950-1000 to 2000. I figured this was a quick idle adjustment so I brought her into the beach and shut off the motor to grab a screwdriver. When I came back the motor was completely dead. No trim, no start, nothing just an electrical click/buzz when I tried to trim or start the motor. Not thinking it was the battery ( since it was 3 days old) I was at a loss and trailer'd her back home. When home I went through the whole motor searching for a, "Loose connection". Nothing. Then for the heck of it I hooked the battery up to a charger and to my surprise it worked.

I noticed some corrosion on the positive terminal. ( Hooked up to a low volt solar charger when parked) The battery tested at approx 12V not under load. Is it likely that the battery was/is bad/overcharged ? ( getting a new battery this week) or is more likely a problem with the Coil, Rectifier, Exciter not charging ? There was no aux. drain on the battery at the time it went dead.

My plan is to try the new battery and check the volts at the battery while the motor is running. What's throwing me off is some people are saying the tach does not work along with the oil pressure light. So whats the rule out/in ? If the tach/oil works, the Coil is Bad or Rectifier ?

Any help would be great

Thanks
Mark

 

[iang6766]

Tacho and oil light works off the CDI/ ignition system. To check charge rate, use a cold meter at the battery, if good it should be over 13 volts when running above 1000rpm.If not charging I suggest getting a workshop manual to troubleshoot.

 

[jgmo]

A 12 volt storage battery has 6 cells. Each cell, when fully charged, will have 2.1 volts
"electrical potential".
Therefore, a fully charged "12 volt" battery will have approximately 12.6 volts potential.
A battery that reads 12 volts is considered to be about 25% discharged.

Sounds weird but true.

I would guess that you're not charging. Like Ian says, you must see over 13 volts ((13.6 in my book) with the engine running for the system to be able to keep your battery topped up.

But, don't automatically assume that you have a bad component that needs replacement. 50% of charging and starting system problems are due to dirty connections. Another percentage are due to bad wiring, damaged/contaminated connector housings or internally corroded cables.

If you have a 1-2-Both switch, that is a usual suspect for faulty connections.

The marine environment, even for trailered boats, is much harsher on these things than with the typical car.

Good luck.

 

[Alan Hicks]

X2 on the likelihood of finding a bad connection vs. a bad part. Make sure you check the ground connections!