Regulator or Stator?

[BassScratcher]

I just purchased a 93 Mariner 200 EFI. I purchased a new starting battery. I noticed after the second time that I had the boat out, that the engine is not charging the battery. The volt meter is only reading 11 volts. The engine has 2 regulators and it looks like it is set up in a split output configuration (20 amps to starting battery and 20 amps to auxillary battery). I've determined by the wiring, that the upper regulator is used to charge the starting battery and the lower regulator is used to charge an auxillary battery. I connected an ohm meter between the 2 short yellow leads from the stator and received .5 ohms. I did the same test to the 2 long yellow leads from the stator and also received .5 ohms. According to the service manual, this is an acceptable reading. Does this eliminate the stator? I think the fault is in the upper regulator, because when I connect the leads to the battery (upper regulator), I do not get the normal spark. When I connect the leads (lower regulator), I do get the normal spark. What's baffling me though, is that the tach is connected to the upper regulator. Is it possible to have a bad regulator, but still get a tach reading? Any help would be appreciated.

 

[Trent]

Re: Regulator or Stator?

While the engine is running check the yellow wires for AC voltages. This will tell if the stator is putting out or not. No AC.....No charge.

 

[oldboat1]

Re: Regulator or Stator?

...and if you are getting AC output, the rectifier is probably burned out -- no conversion to DC and therefore no charging current to battery. I had not heard of a two-circuit system such as you describe, presumably two isolated circuits -- I gather neither battery is getting charged -- perhaps two faulty rectifiers? If the engine was running at some point with one or both batteries disconnected, the rectifier(s) would be damaged.

 

[BassScratcher]

Re: Regulator or Stator?

Where do I test for AC voltage? Across the 2 long yellow and across the 2 short yellow? Am I looking for any voltage out or a specific value?

 

[oldboat1]

Re: Regulator or Stator?

think at this point just noting AC voltage present might be all you need. I think, though, I would find the rectifier and get a replacement, even if you aren't sure about the AC output -- probably $30, and maybe you can find a used one that somebody has tested. It doesn't hurt to have a spare. Substitute a known good rectifier and see if the battery charges.

 

[BassScratcher]

Re: Regulator or Stator?

I think what I'm going to do is switch the upper and lower regulators. As I stated in one of my earlier posts, I think the lower regulator is still good and I do not use an auxillary battery. At some point, I would like to get rid of the split output wiring and change back to using both regulators for the starting battery.

 

[oldboat1]

Re: Regulator or Stator?

But wait -- If one of the charging circuits was not connected to a battery while the motor was operated, the rectifier (at least) for that circuit will likely be shot. Was this rigged by a prior owner? I operated a dual system for a number of years from an Evinrude alternator -- involved installation of a battery isolator in the charging circuit. It worked well, but I think I would have burned out at least the rectifier if either of the batteries had been disconnected while the motor was running -- possibly not, on that system, because a charge would still have been completed to the other battery. But if you have two separate charging systems (dual regulators, etc.) I think either of the circuits will have been damaged if a battery was not hooked up in that circuit while the motor was running.<br /><br />just opinion here ... don't want to overextend.

 

[BassScratcher]

Re: Regulator or Stator?

According to the service manual, the isolator kit can be wired two ways:<br /><br />Split output: 20 amps to starting battery and 20 amps to auxillary battery. This method does not use the isolator.<br /><br />40 amps to isolator: This method has both regulators attached to the isolator and then from the isolator, you can attach two batteries.<br /><br />I may be completely off base, but here is the reason why I think the lower regulator is still good. Again according the service manual, the regulators will cause a small spark when you connect your battery cables. When I connect the leads destined for the starting battery, I do not receive a spark. When I connect the leads destined for the auxillary battery, I do get the spark.

 

[clanton]

Re: Regulator or Stator?

The tach gets signal before regulator, the 2 short yellow or 2 long yellow should have 16 volts AC at idle.

 

[BassScratcher]

Re: Regulator or Stator?

I'm confident that I have confirmed that the upper regulator was bad. Last night, I switched the the lower regulator and upper regulator and now I am getting 14.33 volts at the battery while the engine is running. My next step is to purchase a new regulator to replace the bad one and then re-wire the regulators back to factory (eliminate the current split output configuration). Thanks for all the help.