How much voltage??

[Rapprunner]

Hey Again All,
I got the rectifier back on my motor, secured in place as it should be. See my other thread: "Motor Not Charging - Rectifier".

Any way, once properly installed I started the motor, the volt meter was showing 12.6 to 12.7 volts, this is definitely an improvement as before I would only get readings of 12 volts max, then a decreasing drop. At least now it is greater than 12 volts and maintaining.

My next question; however, is: What would one expect the voltage output to be with the motor running? I was expecting greater than 13 volts, like 13 to 13.5, not 12.6/12.7.

I also suspect that my starting battery may be be bad as I had charged this only a week ago, it was dead today. I put the charger on it, the needle went to 10-12 amps immediately then within 10 minutes it was down to less than 3 amps. It seems to me that the battery isn't actually accepting a charge. This battery is about 5 years old. What do you think, is it a bad battery? Maybe a defunct cell?

Thanks again in advance for any insight/help that you can provide!

Regards,
Howard V.

 

[trendsetter240]

Re: How much voltage??

Hey Again All,
I got the rectifier back on my motor, secured in place as it should be. See my other thread: "Motor Not Charging - Rectifier".

Any way, once properly installed I started the motor, the volt meter was showing 12.6 to 12.7 volts, this is definitely an improvement as before I would only get readings of 12 volts max, then a decreasing drop. At least now it is greater than 12 volts and maintaining.

My next question; however, is: What would one expect the voltage output to be with the motor running? I was expecting greater than 13 volts, like 13 to 13.5, not 12.6/12.7.

I also suspect that my starting battery may be be bad as I had charged this only a week ago, it was dead today. I put the charger on it, the needle went to 10-12 amps immediately then within 10 minutes it was down to less than 3 amps. It seems to me that the battery isn't actually accepting a charge. This battery is about 5 years old. What do you think, is it a bad battery? Maybe a defunct cell?

Thanks again in advance for any insight/help that you can provide!

Regards,
Howard V.

It sounds to me like your battery is past it's useful life. 5 Years is a long time for a starting battery, especially if it's been cycled a lot or stored without a full charge for any extended period of time.

12.6/12.7 is the resting voltage of your battery and likely your rectifier is not charging at all. You should see greater than 13v when the engine is at a fast idle.

My suggestion would be to replace the battery with a brand new one then test it again while hooked up to the new battery.

Cheers!

 

[Rapprunner]

Re: How much voltage??

It sounds to me like your battery is past it's useful life. 5 Years is a long time for a starting battery, especially if it's been cycled a lot or stored without a full charge for any extended period of time.

12.6/12.7 is the resting voltage of your battery and likely your rectifier is not charging at all. You should see greater than 13v when the engine is at a fast idle.

My suggestion would be to replace the battery with a brand new one then test it again while hooked up to the new battery.

Cheers!

Thanks, I sure hope that the battery is the culprit now. I just replaced the rectifier, although I don't think it was bad based upon testing, plus as I said in the other thread it wasn't secured properly.

I am going to replace the starting battery as you suggest and see how it goes from there.

Thanks Again,
Howard V.

 

[14ftgrumman]

Re: How much voltage??

These things won't charge at idle. Replace battery -or have yours load tested first to make sure it's bad- and check voltage at a high idle. Don'g
t know exactly what rpm's, but definatly not at idle.

 

[trendsetter240]

Re: How much voltage??

These things won't charge at idle. Replace battery -or have yours load tested first to make sure it's bad- and check voltage at a high idle. Don'g
t know exactly what rpm's, but definatly not at idle.

At fast idle (1000 RPM) you should see voltage of higher than 13v coming from the rectifier.

You can have your battery load tested if you like but a 5 year old battery that goes dead after 1 week of no use is not something that I'd want as the only means of starting my motor out on the water.

 

[oldrudedude]

Re: How much voltage??

Your rectifier is probably OK. But make sure the connections are good and shiny (including the ground connection). Bad connections can cause a voltage drop. The charging voltage will probably come up to spec when the battery is replaced and the rpms are at cruising speed. Best to measure it cruising speed to be sure. What kind of volt meter are you using for the measurement?

 

[Faztbullet]

Re: How much voltage??

Thats only a 6-9amp system so 12.7 at idle is about right, you will see a slow climb in voltage as rpm increases. At WOT you should see 12.9-13.5 at battery,also do not use a maintenance free battery on a unregluated system such as yours.

 

[Rapprunner]

Re: How much voltage??

Your rectifier is probably OK. But make sure the connections are good and shiny (including the ground connection). Bad connections can cause a voltage drop. The charging voltage will probably come up to spec when the battery is replaced and the rpms are at cruising speed. Best to measure it cruising speed to be sure. What kind of volt meter are you using for the measurement?

Thanks - I too believe the rectifier to be ok, especially since I properly installed the new one today, that is when I started getting readings greater than 12 V @ idle speed.

Now, regarding the volt meter readings, I did not have a multi meter with me so I was relying on the voltage reading from my HB 997. Albeit probably not the best tool for the job it was the only thing I had to measure with at the time.

I will take the battery and have it tested, hopefully that will point me in the next "right" direction!

Thanks to All for the help! I will keep you posted as to my progress.

Regards. Howard V.