90 hp force not charging battery

Joined
Sep 30, 2011
Messages
11
I just realized that my battery is not charging. I read the previous post on batteries not charging and I replaced the rectifier but I am still having the problem. On the old rectifier there was not a wire connected to the negative post. There was a red wire on the positive and two yellow wires. There was also a grey wire coupled with one of the yellow wires. I assumed ((possibly incorrectly) that the grey wire was to the negative and had been incorrectly placed there by the last owner so when i replaced the rectifier I placed the grey wire on the negative terminal. Now at idle I am reading 19-20 volts on the yellow wires (ac) and 70 volts from the red wire to the grey wire. But at my battery I am still reading 12.9 volts at idle. Same as the battery without motor running. So i am sure there is a problem down stream of the rectifier. I read on a previous post that there is a breaker but im not sure where to find it. Did i connect the grey wire to the wrong terminal. If so where the heck is my black wire. I have attached a picture and the grey wire in question is traced in red. It goes into a connector and comes out purple. rectifier.jpg
 

wolfie-uk

Petty Officer 2nd Class
Joined
Dec 8, 2008
Messages
122
Re: 90 hp force not charging battery

your rectifier looks wired incorrectly, it should be marked up with a AC on one post and a + on another, so the two yellow wires go to the AC and the one diagonally from it, the one marked + goes to the live terminal from the battery, and the diagonal one from it should go to earth ( ground), if i remember rightly the alternator does not start giving a charge till about 1000 rpm.
 
Joined
Sep 30, 2011
Messages
11
Re: 90 hp force not charging battery

the two yellow wires are on the ac ( the symbol on the terminals looks like ~ ) the red is on the + and the grey is on the -. Is the grey wire the ground ? Also after the new rectifier the motor starts allot faster but is seems to be skipping now and it did not do that before.
 

bentle

Chief Petty Officer
Joined
Aug 2, 2011
Messages
492
Re: 90 hp force not charging battery

Your grey wire is used as part of the ignition probably a tach or something. It needs to be connected to one of the yellow wires that come from the stater. Either one is fine. It is not a ground. Now the post that the grey wire is connected to is for ground only. You need to run an extra wire from that post to a good ground on your motor. Mine is wired to the starter bolt closest to rectifier.
The other wires all look correct and are correct as long as they are wired as you said in your last post.
 
Joined
Sep 30, 2011
Messages
11
Re: 90 hp force not charging battery

ok, sounds good. You guys are awesome and I really appreciate all the help. I just disconnected the grey wire from the negative terminal. At idle i am reading 20 volts ac from yellow wire to yellow wire. I am also reading about 20 volts dc from red wire to the top bolt on the starter. Does this voltage sound correct? I am going to run a ground wire to the starter in the morning. Do you guys think that the ground wire from the rectifier missing is the reason my system is not charging?
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,817
Re: 90 hp force not charging battery

Well, yes. If the ground wire is not connected to the rectifier and ground no charge will ever be delivered to the battery. On my setup the black (ground wire) is connected right there on the starter mounting bolt shown in your picture. The gray wire is more likely the tach connector which goes to one of the yellow wire from the stator. 20V at idle is pretty high. You might want to double check because there's no way you can have 20 VAC input and then 20 VDC on the output of the rectifier. There will always be a voltage drop internally and also with the load (battery) connected. So double check your readings.
 

bentle

Chief Petty Officer
Joined
Aug 2, 2011
Messages
492
Re: 90 hp force not charging battery

Yes no charge if no ground. Could also be giving you the numbers your getting. Make sure you connect that grey wire back up to one of the yellow wires coming from the stater. Don't run motor until you can get the rectifier grounded properly. You may damage the rect. or the stater. Good luck and let us know what you find out.
 
Joined
Sep 30, 2011
Messages
11
Re: 90 hp force not charging battery

okay, I ran a ground wire and I reconnected the grey wire to the yellow stator wire. Now I am getting 15.5 volts from the yellow wire to the other yellow wire. I am getting 12.7 volts from red to black at a high idle. Seems a little low to me. I am getting 12.5 volts red to black with the motor NOT running. I think my battery is slightly low. Does this extra draw from charging a slightly low battery cause the voltage to be so low or does this sound correct. If this is too low of a charging voltage what should me next step be?
 

bentle

Chief Petty Officer
Joined
Aug 2, 2011
Messages
492
Re: 90 hp force not charging battery

Test it at the battery with motor at idle and see what you get. Should be around 14.5 at charging rate. Your rectifier may already be toast because it was not grounded properly. I will double check that charging rate and post it later.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,817
Re: 90 hp force not charging battery

12.5V battery is not that low but at normal charge. The 12.7 at idle is not bad at all unless your idle is running above 1200 RPM. If it's lower than this then it's normal. You need to rev up the engine at little bit like 2,000 RPM to see if the charging voltage goes up to at least 13.0 Volts and at WOT it should be between 13.5 - 14.5 VDC. Sometimes, it even gets as high as 16.5V! If the charging voltage doesn't come up above 13V then you might have to replace the rectifier.
 
Joined
Sep 30, 2011
Messages
11
Re: 90 hp force not charging battery

Ok sorry it took me so long to get a reply. So i replaced the rectifier again. 12.5 volts at idle 12.5 volts at wot. 15.6 volts ac at idle. I didnt try to test ac at wot going across the lake as i didnt want to loose a finger on the flywheel. But shifting into neutral and idling up made no difference in ac voltage. Are there any fuses or breakers below the rectifier i can check? What suggestions do yall have at this point?
 
Joined
Sep 30, 2011
Messages
11
Re: 90 hp force not charging battery

Ok sorry it took me so long to get a reply. So i replaced the rectifier again. 12.5 volts at idle 12.5 volts at wot. 15.6 volts ac at idle. I didnt try to test ac at wot going across the lake as i didnt want to loose a finger on the flywheel. But shifting into neutral and idling up made no difference in ac voltage. Are there any fuses or breakers below the rectifier i can check? What suggestions do yall have at this point?
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,817
Re: 90 hp force not charging battery

Can you post a pic again of the wiring? If that's a new rectifier, the output voltage at idle should be higher than 12.5V with an AC input of 15.6Vac. Make sure you are reading at the rectifier terminals and not to ground. Voltmeter positive probe (usually red in color) on the + terminal of the rectifier and the negative probe (usually black) on the negative rectifier terminal. If read voltage is still battery voltage (12.5V) it means the rectifier is either bad or improperly connected. Can you also include a pic of the rectifier showing the terminal ID. You can just take a pic of the old rectifier.
 

fucawi

Banned
Joined
May 18, 2011
Messages
1,039
Re: 90 hp force not charging battery

Run a wire from the output of the rectifier ( thats the + ve one) direct to the battery positive and that will make it charge ..you have enough AC volts and if your rectifiere is good and the neg is earthed it will charge...you have a broken wire between battery and rectifier or a miss wire ..it does not have to go through a switch though you might want to fuse it once you have it working ..
 
Top