1991 mercury xr4 150 hp
my battery seems to be not charging when motor is run.
How do I check the charging system? Motor runs excellant. wiring diagram would be helpfull.
thanks.
voltmeter.
the battery should read about 12.7V with nothing running.
with the motor running it should be higher than 13V.
if it is not over 13V you are right it is not charging.
if it is not charging a service manual would be a good investment.
If your engines like mine you have a rectifier that is connected to the stator, I am in the process of replacing my stator as it no longer works properly. When I pulled my stator I noticed that the two wires that connect to the rectifier where dry rotted and corroding very badly (may be a common problem). Or your rectifier is going bad. There is a test procedure in the manual that uses a VOA meter and checks the ohms between the terminals to find if it has a fault. Could also be neglect of the boats wiring and the current from the rectifier just isnt getting back to the battery.
Thanks for the replies, I assume I should check the voltage at the battery first with engine running.
do I put the volt meter on the pos and neg post?
on dc or ac?
Ok, put new battery on , and my volt meter reads
220 dcv ma set on 150dcv with motor running 2000
rpms.
when set on 15dc v--- pegs out.
does this sound right?
my volt meter does not read just dc volts
