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TinarooTriumph
17-08-2015, 07:40 PM
Have just purchased a 25N Yamaha 2-Stroke outboard and have installed a rectifier/regulator from Ebay to charge battery (N70Z - large battery for Minn Kota use).

Question is the rectifier/regulator doesnt appear to be putting too much charge into the battery. I keep my battery on float charge when I'm not using it so the battery is always at about 12.85V or there-abouts. With the rectifier installed and hooked up to the battery the voltage is not increasing at all (this is just having the boat run in the backyard in neutral, half rev's for 10mins). The rectifier is regulated to 14.2V so it will not charge past this point but the battery is just staying neutral at 12.85.
The output on the outboard states 12V/6A (which is only 6amp... doesnt seem much at all?????) Any thoughts?

My 15hp Suzuki 4-Stroke (electric start with rectifier) would charge the battery beyond 14.5V easily, but perhaps this wasnt regulated?

scottar
17-08-2015, 08:50 PM
Could well be normal. Take the meter with you when you use the boat next and try it when you have some more revs on.

BM
17-08-2015, 09:25 PM
Check with Yamaha as you may not have a winding on the stator for running the rectifier (may need a different stator). On a small outboard you will usually only see a fairly small charge current capacity so 6A is about right. However I would be expecting to see in excess of 13V whilst running, particularly at half throttle.

scottar
17-08-2015, 11:20 PM
All small yammy's I've ever had anything to do with had the coil as standard. It will take a considerable period of time with a large battery before you will see any sort of variation. It's the same with my Merc 15 Super and the rec/reg I built and I only use a 75 amp AGM. The volts go to the regulators set limit instantly if the battery is removed from circuit but in circuit, the battery loads the output of the outboard and slows the voltage rise.