Fused wire to Starter

[Tom Glennon]

Well, it was a lovely day on Buzzard Bay Saturday, as I motored from Onset Harbor to Mattapoisett for my haul.  After hanging on a mooring while I finished up stripping sails,etc. so the mast could be hauled, I pressed the starter and there was nothing!  Knowing I had plenty of juice in the batteries, I suspected the starter button, so I pulled the panel, and found everything to be fine.  Going below, I discovered that the wire exiting the fuse holder at the end away from the starter had corroded off.  I stripped some bare wire, cut the fuse holder off and did the same at that end, attached my trusty "jumper wire" I keep in my tool box, and she fired right up.

Now the question is.... what size wire should be used for this when I reinstall the fuse holder?  The schematic in the engine manual says a "#6" but the wire that was there with the fuse holder looks to be no more than 14 Ga.     I picked up an in-line fuse holder at an automotive store with 12 ga wires and it certainly looks more substantial than what was on the engine.
Slow Dance is an '87 with an M25XP.

your thoughts and empirical wisdom would be much appreciated!

[Craig Illman]

Tom - How big is the fuse? That should give you an idea of the required amperage. Then go to: http://www.powerstream.com/Wire_Size.htm and figure in the  15-odd feet of one way distance to the starter button on the panel. That should get you close. I think 12 gauge should be fine. All this circuit provides is voltage to activate the solenoid.

Craig

[Tom Glennon]

Its a 20 amp bus type fuse.

Thanks for the guide!

[Stu Jackson]

Tom,   Starter Fuse Flix

Keep it simple:

1.  Use a step down butt connector from the fuse holder to the existing wire

2.  Use a 12ga (identical) wire from the fuse holder to the quick connect that slides on the starter solenoid (it's way inboard, hard to reach).  Use a new quick connect.

3.  Locate the new fuse holder somewhere (anywhere!) a LOT easier to reach.

4.  We built up from a 5 to a 10 to a 15A fuse, go to 20 only if you have to.

5.  Wire sizing and voltage drop tables don't really bear on this quick repair - the wire's there already, has been working for years except the fuse holder, that's all!   

Here's what we did.  I even marked the purpose and size of the fuse on the holder, although it doesn't show up on the picture.  The solenoid is our glow plug solenoid.

[Craig Illman]

Tom - I agree with Stu, except I'd use a blade-type fuse holder. It's easier to identify amperages with blade style fuses and easier to tell when they're blown.

Craig

[Stu Jackson]

I sure don't disagree with that, because the old style fuses are impossible to read, even with a magnifying glass.  The ONLY advantage is that I don't have to "stock" different types of fuses on the boat, nor different types of fuse holders.  I have a few auto types on the regulator, but still have to write down which type they are since there are two different sizes of those, and I might simply swap them out to "regular" fuses when and if they do go south.  Our 1986 panel is the old style fuse holder panel, so we have quite a stock!

[Tom Glennon]

Thanks Stu for the image.  By the way, what is the solinoid attached to? It looks like its suspended there!

[Stu Jackson]

Tom, it's a "Sky Hook!"  There are two bolts that you can make out in the vertical position screwed into the horizontal wood strip running athwartships at the aft end of the opening.

[Ron Hill]

Tom : Surprisingly, I just had to put in a new starter fuse solenoid holder this last week for the same reason.  The vibration of 20 years had the wire on one end break off!!  Some what of a bear to repair, without removing the alternator, but it got done. 

[Stu Jackson]

Just the other day, after a delightful sail across the Bay the engine wouldn't (re)start.  Nothin', nada, zip, zilch.

I went down below, opened up the engine compartment, and opened up (the VERY accessible) fuseholder (pictured above).  While everything looked fine, I cleaned off the ends of the fuse, reinserted it, and the engine restarted!

Point being:  If you're gonna go to the trouble of replacing the possibly decades old fuseholder, at least put it somewhere easy to get to.

I'm also considering one of those more rugged yellow watertight fuseholders, 'cuz the one I put in is black plastic and most likely getting brittle as well as being in that nasty environment down there.  Another option is to run the wire around the corner into the space under the head.

[Phil Spicer]

Do you really think you canget MORE under the head sink ?

[Stu Jackson]

Do you really think you canget MORE under the head sink ?

But, of course.  The Admiral has insisted that the Krud Kutter and Odlorlos get moved out of sight.