1964 big twin electrical gremlin

kawk

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Jul 5, 2006
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don't understand electric anything. started motor for the first time this year. started right up and ran fine. overnight had a hard rain. tried starting this morning and nothing. in line fuse coming off negative battery post was blown. each time i try to replace fuse,10 amp, it pops. would appreciate if someone could lead me to the next step.
 

F_R

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Well in the first place, the negative post is normally not fused. Secondly, could be a problem with the boat wiring, not the motor. We simply cannot trace the trouble down from a distance.
 

tphoyt

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make sure your wires aren’t backwards from the battery. No reason for the negative to be fused.
 

kawk

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sorry i made a mistake. positive cable has the inline fuse. installed a new inline fuse box. same problem. have a new solenoid that im putting on when the rain stops
 

kawk

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new solenoid installed. still popping fuse. in line fuse wire is red, comes off positive terminal. grey wire comes off negative terminal. both red and gray wire are connected together at back of boat to what i guess is the voltage regulator. cleaned those connections. still popping. would a bad voltage regulator cause a short?
 

F_R

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Well the solenoid factory sold another one. They get replaced needlessly 'most every day. Sorry, I couldn't help commenting.

Anyhoo, your boat obviously is not wired correctly, and we have no way of knowing what has been done. Does your boat even have a voltage regulator? Only used in accessory generator kits. Pictures might help. I do think you are on to something with the red/grey/whatever it is connection. And don't be running out and buying a new voltage regulator.

Your motor isn't Electric Shift is it? It would be a "Lark" if it is.
 

kawk

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im sure my boat isn't wired correctly.. this boat has run for almost a decade without a hiccup. im sure luck has been on my side. and that's the frustrating thing. started right up then the next morning nothing. didn't do anything but turn the key off. motor is not an electric shift. i will take pics of the battery wiring and post later.
 

kawk

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red and green wire connect together on the far right . these are the culprits. red comes off positive with 10 amp fuse. green comes off negative.
 

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F_R

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Well that certainly is not right. I haven't got time to look right now---later
 

Crosbyman

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well... E=R x I E/I=R so 12v/10amps = value R value of 1.2 ohms or...less to blow that fuse

start ohming out the load on the 12 volt distribution side of the blown fuse measuring with Bat. ground

if equal or less than 1.2 ohms begin disconnecting loads along the 12v distribution till ohms jumps UP.

anything lowering ohms below 1.2 ohms will blow the fuse . anything on that distribution which is grounded can be a culprit incl accessories etc...
 

F_R

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Sheese, no wonder the fuse blows. + and - are connected together for a dead short. Not only that, as the decal warns against, the battery + is connected to the field terminal. And even if it didn't burn up the regulator, the field connected to the bat (-) would defeat the purpose of the regulator.

I suggest you disconnect all those small wires from the battery, and see if the motor will start and run (it should). Then, you can sort out all that junk wiring.
 

Crosbyman

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strangely this set up worked for years ??? is the green on the red BAT + wire on the Regulator the same as the green on the Bat - ground post
if I dare ask..:-(

if it is may as well take it off and retry a new fuse. )

some drawings show the BAT+ out of the reg just going to a ammeter
with feeds to START and Choke buttons ... the rest goes to the BAT +12 post to charge the Battery (if so equipped)
 

Crosbyman

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see pic if similar to your more modern engine
 

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F_R

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Sheese, no wonder the fuse blows. + and - are connected together for a dead short.


I suggest you disconnect all those small wires from the battery, and see if the motor will start and run (it should). Then, you can sort out all that junk wiring.

Sorry in my haste, I mis-identified the regulator terminals. Untrue statement deleted.

Even so, I stand by my suggestion to disconnect all those small wires and establish that the motor runs properly, then sort out the wiring. As it is now, it is not the way it left the factory.
 
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