can i run without rectifier

[new2fish]

hello
i put on a new rectifier on my ob,90 hp mariner 1983 sn# 639.. inl 6.
soon i put that think on i have no rpm.can I run without it?

 

[WillyBWright]

Re: can i run without rectifier

Sure can. Just won't charge the battery or signal the tach. The ignition system makes it's own power. If there's no other draw on the battery, you only have to worry about starting current.

 

[ricksrster]

Re: can i run without rectifier

did a new rectifier quit working too?

 

[new2fish]

Re: can i run without rectifier

thanks for the reply.I don't know. Soon i put the new one on ,i had no rpm,if i disconnect the rectifier i have rpm. any thoughts?

 

[TriadSteeler]

Re: can i run without rectifier

When you connect the rectifier, It sounds like you aren't firing on all 6. You need to do a spark test to find out which cylinders aren't firing. Depending on which cylinders are dead, that will help diagnose the problem as to whether it is a trigger problem or a switchbox problem. If I remember correctly (and someone chime in if I am wrong) #1, #3, and #5 are on one switchbox and #2, #4, and #6 are on the other. I'm not sure which cylinders are paired up for the triggers.

Since you have some spark, I'm inclined to believe that your stator is OK.

Do a search on switchbox problems and trigger problems and you will find many people having the same issues you are having. You will also find posts to test each of the ignition components.

 

[new2fish]

Re: can i run without rectifier

Thank you Triadsteeler
Can i run without it? Or i am going to burn up the switch box?

 

[TriadSteeler]

Re: can i run without rectifier

I think you can run without it. The rectifier serves two main purposes.

1. To convert AC Current from the Stator to DC to recharge the battery.

2. To send a frequency of stator impulses to the tachometer.

Keep in mind that I am much more familiar with the older 4 cylinder models with a single switchbox and single coil.

Do a search here for the user Clams Canino. He has many posts on the electrical systems of various models and is definately the resident expert on those types of issues.

With all that said, If it were my engine, I would track down the issue of the cylinders not firing with everything connected and get it running properly.

 

[tashasdaddy]

Re: can i run without rectifier

go to maxrules.com technical assistance. there are testing procedures there. like i said i wasn't sure, but you are getting replys now.

 

[emckelvy]

Re: can i run without rectifier

OK, Silly, Stupid, question, (and I'm assuming this 90 is an ADI motor);

??Why should hooking up the rectifier have anything to do with spark??

UNLESS there's something wrong with the stator that kills the ign charge coils when there's current flowing thru the battery charging coils??

Not sure I understand how a bad trigger or bad switchboxes would be affected by current flowing thru the rectifier. If the motor is running fine with the rectifier disconnected, doesn't that rule out problems in the switchboxes or trigger? (although one of the links below suggests a high-speed miss can be caused by a bad recifier; I'd certainly be interested in a technical explanation for that one!).

Probably be a good idea to check resistance of all the stator windings and if anything looks even borderline, pull the flywheel and check the stator for burn marks.

http://outboardparts.com/mercury/troubleshooting/troubleshooting10.htm

http://outboardparts.com/mercury/troubleshooting/troubleshooting11.htm

http://www.marineparts.com/partspages/Outboard/trouble2.htm

Just brainstorming..............ed

 

[ricksrster]

Re: can i run without rectifier

What do you mean by no RPMS. The engine doesn't run or the tach doesn't work?

 

[Rick_Criswell]

Re: can i run without rectifier

I had a very similar problem with my 84 90hp. Would only go 2000rpm max. Unhook the rectifier and she would scream. Replaced rectifier. Now I got 3000rpm max. ?????
Pulled the flywheel and had a few cracks and brown ooze coming out of stator. High speed windings were going. Replaced stator and everything is good now.

 

[new2fish]

Re: can i run without rectifier

90 hp cdi engine.won't go over 2500 rpm with the rectifier hooked up.

 

[TriadSteeler]

Re: can i run without rectifier

Is it possible that the stator is going bad and not putting out the max current and when the rectifier is disconnected 100% of the available current is sent to the ignition system, while when the rectifier is connected, the recharging system is taking up substantial current and there is only enough left over in the ignition system to produce spark for 2500 RPM?

Just a guess.