Rectifier/Regulator fried, 2004 Johnson 25HP

chuck1252

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Jul 12, 2013
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Have searched but my problem is unique. 2003-4 Johnson 25 HP, Model J25PL4RS. Rectifier/ Regulator is literally fried, and wiring is burned 1 inch back from unit. After searching for replacement, discovered that it is a Suzuki, #32800-89J11. Who knew? Hoping that someone might know what would have caused the french-fry. Hesitant to install the new one, ($240) if there is underlying cause. Thanks!
 

daselbee

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Re: Rectifier/Regulator fried, 2004 Johnson 25HP

Suzuki Outboard 32800-89J11 Rectifier & Regulator - Browns Point Marine Service, LLC

http://www.**********/parts/search/Suzuki/Outboard/2003/DF25/RECTIFIER/parts.html

NOt as high as 240....

Generally, when any electrical part fails, it is due to an excess of load, either a voltage spike in excess of it's ratings, or a current load in excess. That's in general.

So, whenever a rectifier blows I look for too much load on the rectifier circuit, and that usually translates to a bad battery.
Battery gets old, sulfates up the plates, takes more current to even keep it charged...etc. Rectifier works extra hard for extra long, generating heat, just to try to keep the bad battery charged up.

When you put the new one on, use a liberal amount of heat sink grease between the reg/rect and the block for good heat transfer.
Also, that's air cooled....you have a good unrestricted airflow around it? I know it's under the electrical plastic box...but you sure it is being cooled well enough?

That's what I look for anyway.


EDIT: I see the website blanks out competing online parts merchants. I think you should be able to get this reg/rect for about $160.00.
Look around some more.
 
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chuck1252

Recruit
Joined
Jul 12, 2013
Messages
5
Re: Rectifier/Regulator fried, 2004 Johnson 25HP

Suzuki Outboard 32800-89J11 Rectifier & Regulator - Browns Point Marine Service, LLC

http://www.**********/parts/search/Suzuki/Outboard/2003/DF25/RECTIFIER/parts.html

NOt as high as 240....

Generally, when any electrical part fails, it is due to an excess of load, either a voltage spike in excess of it's ratings, or a current load in excess. That's in general.

So, whenever a rectifier blows I look for too much load on the rectifier circuit, and that usually translates to a bad battery.
Battery gets old, sulfates up the plates, takes more current to even keep it charged...etc. Rectifier works extra hard for extra long, generating heat, just to try to keep the bad battery charged up.

When you put the new one on, use a liberal amount of heat sink grease between the reg/rect and the block for good heat transfer.
Also, that's air cooled....you have a good unrestricted airflow around it? I know it's under the electrical plastic box...but you sure it is being cooled well enough?

That's what I look for anyway.


EDIT: I see the website blanks out competing online parts merchants. I think you should be able to get this reg/rect for about $160.00.
Look around some more.



Good stuff to know, and I appreciate the input. Installed a new battery less than 2 months earlier. But....the heat thing just might be the culprit. I drop the skiff off my beach, and it gets bogged down on seagrass more times than not. The buzzer goes off, as well as the warning light on the motor, until I clear the crap. I just might have overheated to a point where the rectifier melt-down happened, or could have happened over repeated overheats. I was thinking of a short somewhere in the electrical lines. I really appreciate your thoughts. Thanks.
 
Joined
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Re: Rectifier/Regulator fried, 2004 Johnson 25HP

Is there any possibility that the battery was ever connected backwards? That'll cook the rectifier in an instant.
 

daselbee

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2,765
Re: Rectifier/Regulator fried, 2004 Johnson 25HP

see that's just it....a short IS an excessive current load.
However it is such a huge load, that it would be noticeable in the form of smoke immediately, not over time...in other words, you would know!!!

The output of the reg/rect goes right to the battery. That is the only load. IF you have some load that is too much for the reg/rect to handle, then the battery would be going dead real soon after you shut the boat down. That load would still be there....

For example....I once had one of those cheap cigarette lighter sockets for a power tap...handheld spotlight use, etc. Over time it rusted up, and began conducting across the two terminals down deep in there. It would draw the battery down. That though is still not enough to burn up a reg/rect.

If you really want to be on the safe side, attach an ammeter between the reg/rect output and the load (battery). In other words, wire it in series. Does that reg/rect have a white wire that goes to the battery? I forget. You have to be very careful. If set on the wrong setting, you might blow your meter up. Too much current through the meter...(as noted above regarding exceeding the electrical circuit's capacity). Set the ammeter up for the greatest current setting, usually they are 10 amps max. Then switch down one setting at a time til it reads actual amps.
Look for say maybe 5-10 amps charging current only for a short time after start, thirty seconds or so, then it should drop off to nearly nothing..maybe less than 1 amp.....all this is off the top of my head....no specs are referenced here....

Are you using a deep cycle marine battery, or a gel cell? Should be regular deep cycle lead acid battery.
 
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