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1990 Johnson VRO 150 battery charge?

M

mwh98

Member
Just opened up the boat for the season and it appears to have a charging issue. Had the boat on the lake for the entire weekend and noticed the battery volyage was only 11.2v, the entier time. Engine off, engine on 1000rpm or 4000rpm. Never had a starting problem and ran the stereo, GPS, and VHF (transmitting frequently) with not change in the volts.

I figured the analog guage in the cluster was going, but the gps has a digital battery meter on it and it gave the 11.2 reading.

Any ideas?

Mark
San Antonio
 
Alternator on an outboard consists of a stator, rectifier, and usually a regulator. On the later model engines the regulator and rectifier are combined in one unit. Charging issues are usually caused by a bad regulator/rectifier. If your battery voltage is the same with the engine off, as it is with it running at cruise, IMHO you have a problem. With a good battery and light load, it should read about 14.5V if it is charging correctly.
 
I thought it may be the rectifier/regulator, however the tach is working fine. Other threads reference the tach not working as a sympton of a blown rectifier/regulator. I could go ahead and change out the rectifier/regulator, but they are $200 and I have to pull the flywheel to gain access to it.

Just hoping for another course before I dig in.

Mark
 
A blown rectifier can affect the tach but it doesn't have to. It all depends on which of the 4 diodes is bad and if its shorted or open.
Your manual will give you instructions for testing it.
 
ibnfshn said:
A blown rectifier can affect the tach but it doesn't have to. It all depends on which of the 4 diodes is bad and if its shorted or open.
Your manual will give you instructions for testing it.
Click to expand...

Or it can affect the tach and not the charging. That's what happened when my 1990 200 Johnson's R/R went out: no tach signal, charging was normal.
 
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