replaced stator and rectifier still not charging

priorlakemn

Cadet
Joined
May 21, 2007
Messages
6
1985 johnson 140hp this motor is new to me. the motor runs well but my tech dosn't work and battery dose not charge. i was told it could be stator or rectifier. i replaced with brand new parts. no voltage coming out of stator. something wrong with the field circrut?
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: replaced stator and rectifier still not charging

I assume your engine has the water cooled voltage regulator/rectifier assembly? If so, the red wire leading from it to the starter solenoid or engine wiring terminal strip should register 12 volts positive (+). Does it?

Or is the rectifier the smaller 3 wire type unit that attaches to the engine with 2 screws/bolts?

Have you taken a ohm meter reading of the 2 yellow wires leading from the stator? Disconnect the wires before taking a reading.
 

priorlakemn

Cadet
Joined
May 21, 2007
Messages
6
Re: replaced stator and rectifier still not charging

yes it is a water cooled rectifier. i will check for 12 volts on the red wire today. I checked stator ohm reading on yellow wires it was ok.
 

cbucking145

Recruit
Joined
May 21, 2007
Messages
3
Re: replaced stator and rectifier still not charging

I get 12.43 from that red wire coming from starter solenoid to the rectifier.
 

cbucking145

Recruit
Joined
May 21, 2007
Messages
3
Re: replaced stator and rectifier still not charging

How can i check if the powerpack is supling power to the stator.
 

ezeke

Supreme Mariner
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Sep 19, 2003
Messages
12,532
Re: replaced stator and rectifier still not charging

Start a new thread, cbucking145, You will get the answers that you need.
 

cbucking145

Recruit
Joined
May 21, 2007
Messages
3
Re: replaced stator and rectifier still not charging

same person differnt computer i am priorlakemn
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: replaced stator and rectifier still not charging

Put your voltmeter on the battery posts and take a reading with the engine off. Start the engine and take a reading. If the reading went up at all the rectifier is at least partially working.

The powerpack has nothing to do with the charging circuit. The rectifier takes AC voltage from the alternator and converts it to DC voltage for charging by using multiple diodes.

The diode basically allows the flow of current in only one direction. Diodes are easily damaged. Just reversing the battery cables for an instant or disconnecting while running will destroy them. The most common cause of rectifier damage is loose or failing battery cables.
 

priorlakemn

Cadet
Joined
May 21, 2007
Messages
6
Re: replaced stator and rectifier still not charging

the reading was the same. there is no voltage coming from my Brand New $250 dollor Stator
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: replaced stator and rectifier still not charging

Perform the following tachometer test. If the tachomer operates as it should when connected to the yellow wire, the stator is fine.... and most likely the water cooled voltage regulator/rectifier is faulty. Be sure to do the test accurately as follows, then let us know the results. I'm assuming you did not replace the regulator/rectyifier assembly..... you didn't say.

(Testing Tachometer With Water Cooled Regulator/Rectifier)
(J. Reeves)

A quick check is to simply plug in a another new tachometer as a piece of test equipment. If the new tach works properly and the old tach didn't, obviously the old tach is faulty.... but usually boaters don't carry around a spare tach (see below).

A faulty rectifier wouldn't damage the tachometer, the tachometer simply wouldn't work. This is due to the fact that the tachometer operates off of the charging system and the rectifier converts AC voltage to DC voltage, enabling the charging system. A faulty rectifier disables the charging system, and the tachometer simply doesn't register.

However.... those watercooled regulator/rectifiers that are used on the 35amp charging systems (and some others) bring into play a different type problem, and as you've probably found out, they are really a pain to troubleshoot via the proper procedure. There's an easier way.

The tachometer sending/receiving setup operates off of the gray wire at the tachometer. That same gray wire exists at the engine wiring harness which is connected to the engine electrical terminal strip. You'll see that there is a gray wire leading from the regulator/rectifier to that terminal strip, and that there is another gray wire attached to it. That other gray wire is the wire leading to the tachometer which is the one you're looking for.

Remove that gray wire that leads to the tachometer. Now, find the two (2) yellow wires leading from the stator to that terminal strip. Hopefully one of them is either yellow/gray or is connected to a yellow/gray wire at the terminal strip. If so, connect the gray wire you removed previously to that yellow/gray terminal. Start the engine and check the tachometers operation, and if the tachometer operates as it should, then the regulator/rectifier is faulty and will require replacing. If the tachometer is still faulty, replace the tachometer.

If neither of the yellow wires from the stator is yellow/gray, and neither is attached to a yellow/gray wire, then attach that gray tachometer wire to either yellow stator wire, then the other yellow wire, checking the tachometer operation on both connections.

I've found this method to be a quick and efficent way of finding out which component is faulty.... the tachometer or the regulator/rectifier. It sounds drawn out but really only takes a very short time to run through. If the water cooled regulator/rectifier proves to be faulty, don't put off replacing it as they have been known to catch on fire with disasterous consequences.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store
 

clanton

Rear Admiral
Joined
Jul 9, 2001
Messages
4,876
Re: replaced stator and rectifier still not charging

There should be app 18 volts between the 2 yellow wires using a peak reading meter. If you are getting this and the stator ohms, and short to ground checks , connections are good, magnets in flywheel good. replace the regulator.
 

seahorse5

Rear Admiral
Joined
Jan 24, 2002
Messages
4,698
Re: replaced stator and rectifier still not charging

IF your regulator has a purple wire on it, check that it reads 12 volts when the key switch is turned to ON and the motor not running. The charging system will not operate without the 12V.

Late model factory replacement regulators do not have a purple wire on them.
 
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