Rectifier? Who knew?

[davejohnson]

Confession here: I bought my old boat 2 years ago, with a 1977 Mercury 900 inline six on the back...and I knew *nothing* about outboards. Long story short, I got a book and lots of trial and error and busted knuckles, and the motor runs fine now. I've always rotated/charged my batteries out every six or seven trips when they'd run down. I never knew a rectifier existed that was supposed to charge the battery. (yes, I'm retarded). Actually, I'm so much more concerned that the thing runs, that I accepted the battery situation. Well, I ran my meter test on the rectifier today, and it is indeed bad. (Looks bad too). So, do I just replace that little block with the three leads on it, or is there more to replace? And is $25.99 too much for that block? So far, I could only find one online. Thank you.

 

[Laddies]

Re: Rectifier? Who knew?

You can ck the alternator windings (yellow to yellow) and make sure you have continuity if you do then all you need is the rectifier--Bob

 

[molsenice]

Re: Rectifier? Who knew?

not knowing any "data" about the motor - make model - hp? Try old mercs.com - grubbs marine - nice folks. Replacing it will help battery

 

[emckelvy]

Re: Rectifier? Who knew?

Try Sierra 18-5707, replaces Mercury 62351A1, 62351A2, 816770. Check out the factory part #'s at www.mercurypartsexpress.com and for good deals on Sierra aftermarket parts, www.boatfix.com <br /><br />The Sierra parts pricing query is here:<br /><br /> http://www.boatfix.com/searchsierra.asp <br /><br />You might also search this forum on "Radio Shack" as I believe there have been some discussions on using a Rad Shack rectifier in a marine application; the Rad Shack part is considerably cheaper.<br /><br />HTH............ed

 

[JasonJ]

Re: Rectifier? Who knew?

Don't feel too bad, I did the same thing for most of the first season I ran my current rig. Replacing the rectifier fixed it, and I also gained several hundred rpms because those ignition systems really need optimal amounts of juice.

 

[davejohnson]

Re: Rectifier? Who knew?

Thanks to all who replied. Solid advice as always.

 

[etienne]

Re: Rectifier? Who knew?

Dave, thanks for sharing your story, similar situation, trying the Radio Shack route. How did yours turn out?

 

[etienne]

Re: Rectifier? Who knew?

Success! Here are the steps:<br /><br />1) remove Merc regulator (unbolt wires & housing)<br /><br />2) pry off metal baseplate & grind smooth.<br /><br />3) drill a countersunk hole in the center of the <br /> plate so a tapered head bolt will sit flush.<br /> <br />4) put thermal grease (from computer store) <br /> between the regulator and the plate<br /><br />5) bolt on the Radio Shack regulator ($5) & <br /> threadlock so it doesn't vibrate loose. <br /><br />6) replace Merc wire terminations with spade type <br /> or solder directly to regulator. Use heat <br /> shrink tubing to protect connections.<br /><br />7) solder negative terminal to motor housing <br /> ground since Radio Shack has 4 leads & Merc <br /> internally connects 2 together.<br /><br />8) put thermal grease on back of base plate & <br /> bolt on using original bolts & holes.<br /><br />Nice to have a fully charged battery without lugging the thing around to charge it!

 

[mnw001]

Re: Rectifier? Who knew?

I've used the same bridge rectifier for schack on omc's worked great

 

[timmathis]

Re: Rectifier? Who knew?

Simple as 123.