1990 - 120 HP Force Outboard Not Charging Battery

Steveh79

Recruit
Joined
Aug 31, 2016
Messages
3
I have been reading the Threads but have not found one directly related to my specific HP. I'm not sure if it makes a difference, because I'm new to outboard motors so please bare with me. I just bought a boat and was out on the water when I went to start it and the battery would not turn it over. I flagged someone down for a jump and after charging the battery for a minute through jumper cables it fired right up. I brought it home and started my research. Everything points to the rectifier or stator. I ordered a new rectifier and installed, but upon doing so, I tightened the ground to much and broke the ground lug. Out of frustration I went ahead and fired up the engine. To my surprise the motor was idling beautiful which it never did before. It actually stayed running for like 5 minutes without stalling. I have been nervous on the water because whenever I pull into the dock it always would stall when I'm going to put it in reverse to stop and tie off. I was told that because its a 2 stroke they don't really like to idle and being I was new to boating, like a dummy I believed them. Back to the issue though. Being I broke the rectifier ground I had someone hold the ground wire to the lug that broke off. I ran a couple of test but not sure if they're accurate. Anyway it still wasn't charging, but was idling great. I noticed the RPM gauge wasn't working anymore either. I ordered the new rectifier and a stator just in case. If I install the new rectifier (without breaking it) and it doesn't charge the battery, my next step is the stator. Correct? Also I can't find a tag that shows what exact engine I have. The only tag is a little white sticker that says 1201A90A. Can anyone help with this or point me to where it might be inscribed in the engine? All help will be greatly appreciated.
 

Steveh79

Recruit
Joined
Aug 31, 2016
Messages
3
Thank you for the information. I will be working on it today and will post the results. Thanks for the video links as well. I had a hard time finding anything on a force motor.
 

Steveh79

Recruit
Joined
Aug 31, 2016
Messages
3
So I installed the new rectifier. I put the lead for the RPM gauge on the other rectifier lead as suggested. It worked! Okay, So double checking all connections including ground the best voltage reading at the battery with the engine revving between 2800 and 3000 RPM was 13.48 VDC When I back it off and it was at idle it was staying around 13.08 VDC.. With the old one on it was at 12.78 VDC with the engine running. to me it still doesn't seem like that's is good enough but maybe it is. Also, I was thinking maybe the voltage will go up with the throttle opened all the way up on the water??? Other noticeable differences was the fact that it idles nicely now. Now only that but it starts up without hesitation which it did the whole time I have owned the boat. It has always hesitated when starting even after warming up.:confused: PNWBOAT, please let me know what you think. If you think I should replace the Stator or not.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,817
The rectifier/regulator is working as designed. Even at WOT rpm, the most you will ever see is probably just around 13.5~14.0 volts. The reason for this is because your charging system has a voltage regulator that is designed to dump over voltages past 14.0 volts to ground. I say you are good to go.

Now remember, the charging system is rated only at 7 amps which is roughly equal to 84 watts only. Yup, if you have many elex equipment running that is barely enough before you actually discharge your battery.
 

pnwboat

Rear Admiral
Joined
Oct 8, 2007
Messages
4,251
I would agree with Jiggz in that your charging system is working properly now. I would hold off on replacing the stator.

If you have the rectifier that has 4 lugs on it, the charging voltage may go as high as 15 to 16 volts at WOT.

If you have the rectifier/regulator that has 4 or 5 wires (depending on which model) coming out of it, then your charging voltage should not go over 14.5 volts.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,926
Do like a lot of boaters do: install a 2nd battery and a switch.
They sell different switches.
The base one just turns the battery off or changes to the other battery.
Should be used when not running.
The better ones are ignition protected.
And can be turned when the motors on.
I've got the cheaper one.
 
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