Charging System on a 850.

[Ace1948]

I have a two part question.
I need some help checking my Charging System.
I have a Mercury 850 motor the serial number is 4423397.
The best I can tell is it's a 1975 motor it has CDI Ignition I don't
know if the power head has been changed. Is there any where
on the motor I can find a ID number to verify the year model?

I would like to check my Charging System to see if it's charging.
Any help would be appreciated.

 

[Moody Blue]

Re: Charging System on a 850.

With the motor running at a fast idle (1200 rpm), measure the battery voltage with a digital voltmeter.

If it reads between 13 and 15 volts, then the charging system is working. If it reads 12V or under, the charging system is not working.

As for tracking down the S/N, you can look in a few places. The standard place for the engine S/N plaque is on the front of the tilt tube between the transom clamps. Failing that, you can look in one of two places on the powerhead. First is on the top starter motor mounting bracket. Next place to check is on the distributor mounting bracket.

 

[Ace1948]

Re: Charging System on a 850.

Thanks for the help.