Charging Systems

[mnmfors]

Hi, I have no charge on my 1986 90hp Mercury. <br /><br />Is anyone willing to help me trouble shoot?<br /><br />I have an earlier topic that describes this problem in detail, however, we can start from scratch.<br /><br />I have a new battery, starting, not deep cycle. It is 1000 CCA. <br /><br />I Disconnected the battery switch I had on it, hooked up battery direct, that did not help.<br /><br />It has a new stator, and tested good.<br /><br />I would guess to get a new rectifier? <br /><br />Thanks for any help.

 

[jee70611]

Re: Charging Systems

I don't know whether you have a voltage regulator or not but if you don't I would suspect the rectifier. Also, check all the wiring between the battery and rectifier. You might want to make sure you connected the wires in the correct places. An easy way to troubleshoot the rectifier, in my opinion, is to turn the key to the run position and check for battery voltage at the rectifier on the wire that runs to the battery. Good Luck and keep us posted. <br /><br />James<br /><br />PS: If you do have a regulator, I would check it first.

 

[Down South]

Re: Charging Systems

mnmfors, I read your other post. I would think that your rectifier is bad from all that you have done so far. Do you have another Mercury motor that you can swap the rectifiers with? This is one way that I did this one time. I had an old 85hp mercury that wasn't charging. I swapped the rectifiers with a 50hp Mercury that I had to check it. Sure enough it started charging. I'm sure there is a procedure that can be performed with a multi meter to check the rectifier but I wouldn't know how to do it. Maybe you have a friend that has a Merc that has the same rectifier you can borrow for a little while. Another possiblity would be someone who has an outboard repair shop. They usually will have one or two rectifiers around off junked motors.<br />Anyway, Good luck,

 

[mnmfors]

Re: Charging Systems

Thank you for the replies. My CPU has crashed, so it will be some time between posts. (I am using a friends CPU)<br /><br />Jee, I will check the voltage at the rectifier. If I do happen to have voltage, should I try to "hot wire" (bypass system), and if so, which pole do I use?<br /><br />Down South, that is funny you say that, I tried using my old 115 merc's rectifier, and it did not work. After further inspection, I noticed one of the poles was loose, so that basically told me nothing. <br /><br />If the "hot wire" doesnt work, I think a good place to start is a new rectifier.

 

[clanton]

Re: Charging Systems

I dont know what this motor has , but radio shack has a rectifier that looks like the one in the book, I think it was under 10.00 and rated at 50 amps.

 

[mnmfors]

Re: Charging Systems

Thanks Clanton, I will check that out.<br /><br />I just came from radio shack too, got a power cord for my laptop, so I am back on line.<br /><br />I will post my results as soon as I replace the rectifier

 

[petryshyn]

Re: Charging Systems

mnmfors<br /><br />First off, don't bypass or jumper the charging system. It won't do any good as the voltage applied to the rec. is a/c, and jumpering can burn the stator if left connected.<br /><br />Secondly, before buying anything, if you have a multimeter, you can check for proper rectifier operation and voltage being applied from the stator as well.<br /><br />*if you have access to a meter, let us know and we'll guide you through....

 

[mnmfors]

Re: Charging Systems

Yes Schematic, I would like to do that. I wasnt sure if you were still willing to help. I will get the multi meter, I checked them out at radio shack, ranged from $20 to $90. If you wouldnt mind, let me know which one to get again. I thought I remembered you said to get one with a diode tester or something. I should just get one that says multimeter on it?

 

[petryshyn]

Re: Charging Systems

buy or borrow a digital meter that has the diode test function in it. You don't need to spend a whole lot of money..<br /><br />Even this one will do....<br /><br /> click me