Question about rectifier

hyde11

Recruit
Joined
Aug 29, 2008
Messages
2
Hi all,

I have an 1985 Evinrude 90. Starts fine, runs OK...though coughs every 20 seconds or so on idle. I have found my battery draws down after a couple of outings, so I tested my rectifier by checking for voltage at the battery running and off and see no difference. I also disconnected the battery while running, and found the rectifier is delivering 1.82 volts (I figure it should be around 14). So, it appears that the rectifier is not working properly, however, I am not sure. I have a few questions.

First, the VRO has been disconnected (prior owner)...could the way this has been done affect the charge generated by the rectifier? What is the proper way the rectifier should be wired with the VRO disconnected (wouldn't be in the manual)? How do I test?

Second, if the rectifier is not working properly, could this explain the cough every 20 seconds...like voltage is building up in the stator and then gives off every 20 seconds disrupting ignition? Or is the cough a separate issue? I have checked the timing and it seems OK. Also have new plugs and leads in the engine.

Third, do I need to replace the rectifier if it is not working...or can I just charge the battery now and then, and keep an extra in the boat for emergencies? What impact will just leaving it have?

Thanks.
 

hyde11

Recruit
Joined
Aug 29, 2008
Messages
2
Re: Question about rectifier

More digging on the forum here, and I see I should disconnect if it is the rectifier. So, I answered one of my questions. Still not sure the problem isn't related to the VRO...I will keep digging.
 

R.Johnson

Rear Admiral
Joined
Sep 24, 2003
Messages
4,446
Re: Question about rectifier

If you run the engine with the battery disconnected, now you probably do need a rectifier. The VRO does not effect the rectifier. The backfire means a lean condition. First, sync, and link, then adjust the low speed needles. If that don't help, clean the carbs.
 
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