1990 Johnson 90 hp V4 Charging

[Marinewithaboat]

What is the easiest and most effective way to see if my motor is charging my battery properly?

 

[Dhadley]

Re: 1990 Johnson 90 hp V4 Charging

A voltmeter.

Does the tach work? If so, at least one side of the charging system is working.

Does your battery go dead?

 

[Marinewithaboat]

Re: 1990 Johnson 90 hp V4 Charging

Tach works. I had one battery die on me, last time out the voltage was getting real low on the battery but we were trolling alot. Does the motor not charge the battery at low rpms?

 

[Dhadley]

Re: 1990 Johnson 90 hp V4 Charging

It will but it only peaks after 2000-2500 I believe. Might be higher. And remember you only have a 9-10 amp system.

Now, when you say you were trolling do you mean with the outboard or a trolling motor? Once the motor is running it won't pull anything from the battery. If you run other things, lights, radio, depthfinder, GPS etc, they will.

 

[Marinewithaboat]

Re: 1990 Johnson 90 hp V4 Charging

Yeah trolling/idling with the motor itself. Did have the fish finder running. I just dont understand how a fish finder can drain the battery. Does it really pull that much from that battery. It was on for almost 5 hours I guess.

 

[Dhadley]

Re: 1990 Johnson 90 hp V4 Charging

I wouldn't think a ff could drain a healthy battery in 5 hours. How old is the battery?

 

[Marinewithaboat]

Re: 1990 Johnson 90 hp V4 Charging

Maybe one year.

 

[Walker]

Re: 1990 Johnson 90 hp V4 Charging

I think fishfinders are only 1.5 amps so I wouldn't think that drew your battery down. Your dash guages probably draw more than that.

 

[Silvertip]

Re: 1990 Johnson 90 hp V4 Charging

If the battery was not fully charged when you left the dock, then made a very short run to the fishing hole, then a short trip back, the battery will not fully charge. It takes a fairly long run at high speed to bring a discharged battery back to anywhere near full charge. If your voltmeter reads 13.5 - 14.5 volts at anything above 2000 RPM its charging.