Battery fuses

[Jamie 10017]

Does anyone use a fuse between the battery and the starter ? I know it's not required by ABYC but some people use them. I will use them between the battery and the main switch but I was thinking about the starter cable , what if the solenoid welded itself together or something freak happen. I have 2 498 BBC and I was thinking of 300 amp used on a 1/0 cable what do you think of this set up? I would rather the fuse be smaller than what the cable could stand amp wise. just getting ideas for my wiring install. Thanks Jamie

 

[jtybt15]

Merc used to have a 90 amp(I think) circuit breaker/fuse on some starters. Not really sure why they had them or why they stopped. Since it could have a disastrous outcome, my guess is the wiring within the starter would burn up if something internal grounded.

Now if a battery cable grounded, that'd be another story.[:O]

 

[Billylll]

The resetting type breaker are on my Merc 2005-07 8.1L HO's right at the starter. I think they are > 90 amps though. There is also one <90amps near the top of the engines wiring harness conector.
Bill

 

[alien1952]

There are no starter fuses,breakers, etc. There is a 90A system fuse on the starter. This goes to the 50A resetable breaker on the engine, then thru the rest of the boat. The marine battery switch either on=off or 1 - both -2

 

[Pa Mikee]

Fusing circuits is not a bad idea. The only downside is that it creates additional connection points that may corrode or come loose. If I were to fuse the starter, I would fuse it at least 150% of the maximum starter draw; or the minimum ampacity of the the cables. My main battery bank can put out over 4000 cranking amps. It wouldn't take long for my 2 gauge starter cables to catch fire on a dead short.

 

[Jamie 10017]

The fuses I'm speaking of go into the starter cable form the battery to the starter. ABYC does not require them as of now but they recommend them. It's my understanding that they will soon be required on new boats. My OEM harness had 60 amp breakers in the start wire running from the switch to the solenoid. Blue seas makes a fuse that mounts directly onto the battery. I just thinking of things that could go wrong and start a fire or worse, I'm not real sure about if I am going to fuse the starter or not just looking for ideas and thoughts.

 

[Billylll]

I use large class "T" type fuses from my 4/0 wiring from the 2 house banks and the thruster bank on my boat.
Jamie I always carry a set of 24" Greenlee cable shears on-board if the fuses didn't work and I could get to a point in front of the DC feed that was melting down.
Properly mounted and rated battery switches should disconnect if you have a runaway starter or DC meltdown.