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1985 Merc 115hp Not charging

Re: 1985 Merc 115 Not charging

Looks like a good job in restoring the boat.-----------Not many people recognize the fact that glass boats have wood in them. worse yet many are out there on the lakes.----------------The first thing to check would be the stator.Yellow wire to yellow --ohms are ?----------then one yellow to ground --ohms are ??---------------the rectifier is checked and the diodes only let current go one way. I do not have a manual handy ( in the shop )---------------Most likely the rectifier is bad.
 
Re: 1985 Merc 115 Not charging

Looks like a good job in restoring the boat.-----------Not many people recognize the fact that glass boats have wood in them. worse yet many are out there on the lakes.----------------The first thing to check would be the stator.Yellow wire to yellow --ohms are ?----------then one yellow to ground --ohms are ??---------------the rectifier is checked and the diodes only let current go one way. I do not have a manual handy ( in the shop )---------------Most likely the rectifier is bad.

Thanks......I assume I can check the rectfier lead to my battery to engine ground and if I don't get 13 + v that part of the rectifier is bad and the rectifier needs replacing. As stated, my tach is registering so that would mean my stator is working and the rectifier is ok to the lead to the tach. Make sense ?? Don
 
Re: 1985 Merc 115 Not charging

If your tach is working it means that the charging system is working.-----------------What voltage do read on the battery with engine not running. -What voltage do you read with engine at a fast idle ( 1500 RPM )
 
Re: 1985 Merc 115 Not charging

Let me butt in on this one. I have a 1987 115 Mariner (Merc) that had a faulty stator, causing the alternator not to work, but the tachometer worked fine. The volt meter read 12.5 volts at WOT and after replacing the stator it now keeps the battery up and show 15 Volts at WOT. The tachometer never missed a lick either way. Were the Mariner's wired differently than the Merc's?
 
Re: 1985 Merc 115 Not charging

Replaced the rectifier and it's showing 13.4v at 1200 rpms......... Should it be higher - 14+ ??

Don
 
Looks like the rectifier was the culprit.----------13.4 at a fast idle means that it is charging,at full throttle it will be more.
 
You are in good shape now. It depends on what diode in the full wave bridge rectifier goes bad as to how it affects the tach. One side of it can be bad and if the tach is connected to the other side, sometimes it will work fine.
 
The " tower of power " is a wonderful motor.------------Many people do not like them anymore for some reason.-------------Maintain it with regular new impeller, check bleed inserts, run carburetors out of fuel when not in use for more than a week,and use top quality oil.Then you will enjoy it for a long time.
 
Bleed inserts ?? I am a litle confused.....Any pics of where they are and how to find out if they need replacing and do they help the idle. I can't seem to get my Merc down lower than 1000 by adjusting the throttle cable back as far as it wil go. It likes to stall out when put in reverse at 1000.Drops down when in gear and I have to throttle up a bit to keep it running. Pain when coming into the dock and it stalls and you have no reverse !

PS Do you know David Scott ?? http://www.scottcraftboats.com/index.html
 
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I do not know that gentleman.-------------Your idle should be a lot better than that ( compression #'s are ?? )-----------Bleed inserts are wee plastic bits that tend to get blown out or fall out.-------They are found just inside the tranfer port covers ( 5 of them ) for 6 cylinders.This also allows you to inspect pistons and rings.-------they do change idle characteristics.-------------Go to ----------------"' fiberglassics.com "-----------for more discussion info on them.
 
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