rectifier heats up

[dreamchaser]

have a 1983 evirude 115 ,replaced rectifier and new one is heating up temp is roughly 135f have been pulling my hair out tryin to find the problem any suggestions would be much appreciated

 

[ezeke]

Re: rectifier heats up

Probably on the battery side. You may be trying to charge a bad battery, a auto battery, or a battery that has been excessively discharged. Try charging the battery with a charger first and see if the problem goes away.

If you are trying to run a lot of accessories with an unregulated rectifier you may have a continuing problem.

Another possibility is that the cables are bad or badly connected. Feel the cables at the battery connection the next time you start the motor. If the terminals are hot, check and clean the connections. Often the cables corrode beyond the visible portion of the wire, the heat will be a tip-off.

 

[F_R]

Re: rectifier heats up

If I may speak in generalities here, rectifiers normally produce heat. And the higher the current, the more heat. That is why they are mounted in some sort of heat sink to carry the heat away. Offhand I would say your motor is probably perfectly normal. I don't know if your motor has any sort of current regulation other than the built in capacity, but I doubt it.

 

[ezeke]

Re: rectifier heats up

I agree generally with F_R. However, if you think the heat you are experiencing is excessive, or, if you want to assure that you will not be replacing the rectifier unnecessarily, you may want to check the items that I mentioned anyway.8)

 

[dreamchaser]

Re: rectifier heats up

thks for the leads guys ...as for the rectifier being normally hot well the old one was burnt out this leadin me to believe maybe it was caused by to much heat. ie wires burnt off no guts left of the diodes ..this am took fully charged battery from truck checked all terminal leads checked the grounds and positives good contacts everywhere as i can tell .started the motor up ,no accessories on. and the same heat at the rectifier, im hoping it isnt a issue like u say ....oh and also this motor does have a seperate voltage reg if that makes any diff? thks for ur input 8)

 

[F_R]

Re: rectifier heats up

Rectifiers get burned up by loose or dirty battery connections and/or battery cables being installed backwards....even if only for a split second will do it. NEVER disconnect the battery with engine running (same as loose connection as far as the rectifier sees it). I still don't think you have a problem unless the output is shorted to ground (?).

 

[dreamchaser]

Re: rectifier heats up

ok so now im almost on the water getting ready to take it out for a sea trial as i had just powered up from a 90hp rude ..i dont know the history of this 115 but had some wirin issues that i fixed ,changed the control box out as well and everything is good now, but this new rectifier is the only thing keepin me on land" shorted to ground "the red wire u mean from the rectifier ? how do i go bout checkin it? thks

 

[F_R]

Re: rectifier heats up

Reading back over all this, have we established that the rectifier is working and the battery is charging? Does it heat up just when motor is running or does it get hot even if it is not running. If it gets hot without running, it could already be burned up (shorted diode) and battery is feeding back through it into the stator or to ground. Re-read the cautions about loose/backwards/disconnected cables.

 

[dreamchaser]

Re: rectifier heats up

only heats up when it is running ,havent tested the new rectifier yet as it is new 2 days ago ....all cables and connections are hooked up properly ..well im off to work gonna leave it for another day ....thks guys what a great site.....