79 Evinrude 35HP - how bad is this?

CatfishMN

Petty Officer 2nd Class
Joined
Jun 14, 2009
Messages
170
So I took the boat out of the garage today to fire it up in a barrel after sitting all winter. I went to hook up the battery and for some reason I reversed the connections. I know, I know, I feel like punching myself in the face.

I believe the key was in the on position. I saw a spark, and disconnected. I think the cables were backward for maybe 5 seconds. I looked back at the motor, and there was smoke coming out from under the cowl. I let that clear, and then tried it again. Sometimes the starter spins fine, others it seems sluggish and will 'chug' really slowly. I did notice that the starter gets uncomfortably hot if the ignition wires are hooked up to the battery, but then it cools down if they are removed from the battery.

My question is - what did I damage? I did find a small inline fuse toward the back of the motor, and it had not popped. I have not had the motor running since this happened.

Any help is appreciated. Oh yeah, I bet I NEVER do that again.

Thanks!
 

bonz_d

Vice Admiral
Joined
Apr 22, 2008
Messages
5,274
The fuse is to protect the ignition circuit from a short or over voltage should not have affected the starting circuit as there should only be power there when the key is in the start position not the run position. Though it certainly sounds as if you have a starter motor problem.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
You absolutely blew the rectifier for sure. And possibly, but not likely, the stator as well. When you connect the cables backwards, the rectifier destruction is instant. You can't disconnect it fast enough to prevent it. The battery is not connected to the power pack,, so don't worry about that.

Disconnect all wires from the rectifier and see if everything else works.
 

CatfishMN

Petty Officer 2nd Class
Joined
Jun 14, 2009
Messages
170
Thanks for the responses. I switched batteries and was able to start the motor and it appeared to run as normal, but with the amount of smoke that came out, I am sure something burned up, most likely the rectifier. Will everything run normally without the rectifier (until I replace it)? The battery won't charge, of course.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Depending on which way the rectifier shorted it may hurt the stator if you keep on running it. I'd replace it asap.
 

CatfishMN

Petty Officer 2nd Class
Joined
Jun 14, 2009
Messages
170
Thanks Boobie. After closer inspection, the rectifier is definitely burnt. I ordered another on tonight and won't be running it until I replace it.
 

jasper60103

Commander
Joined
Sep 18, 2008
Messages
2,055
Yes, spring has finally arrived in Minnesota, I think. LOL.
I did my first startup this weekend as well. In a rush to hear the ole girl come to life,
I reversed the fuel hose. I did discover it before firing her up though.
Hope it all works out.

-jasper
 

NicoPags

Petty Officer 1st Class
Joined
Mar 24, 2014
Messages
217
Did something like that once myself too. I ended up destroying the brushes in the starter. Very simple repair which could have been avoided. Might make sence testing the starter since you have the time at the moment. Or let a sleeping dog lie. Not sure if yours was working 100% after the battary swap. You did mention it started though. Best of luck hope she works for ya
 
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