Starter and Ground Cable Size

[Rick Johnson]

I've looked at all the topics I can find, but it's not clear to me.  What is the largest cable size that can be run through the single conduit to the starter and ground?  I know the C34 comes stock with #4 and I've see that others have pulled #2.  Is #2 the largest that will fit and has anyone run #2 or larger outside the stock conduit?

Thanks,

Rick

[Ron Hill]

Rick :  It's not the size of the cable that you can pull; it's what size do you NEED?!!
A #4 is what I've got and has worked for 19 years.  Some people have added another #4 or changed out to #2.  The real key to my lack of problems is that I've crimped and SOLDERED all of the battery cable connections. 
I also added another #8 negative wire from the batteries to the negative bus bar.  I also have a negative #4 from the alternator direct to the negative on the batteries.  In other words I have many paths for the negative flow. 
A few thoughts.   

[Craig Illman]

I got some surplus 1-1/2" flexible network fiber duct from a data network contractor. We ran it from under the head sink to next to just forward of the water heater and under the house bank. We managed to pull, I believe, one #1 and two #2 cables through it. Also there's the regulator high temp sensor wire and one other small gauge (18/2) wire. This new conduit keeps the battery cables out of the bilge and protected from any chafe. The factory conduits are pretty small. Maybe a bit overkill, but not if you follow Calder's recommendations. The factory wiring really needs to be crimped and soldered as Ron recommends. The starter pulls 150+ amps and my alternator is 80 amps. My starter battery is forward of the mast and needs a large gauge to deliver optimal watts. I wanted my alternator to be able to maximize it's capbablity to the house bank. My shore-power is likely to be on overnight, so I'm not so concerned about it's efficiency and therefore used the factory wiring from the panel back to the house back, without supplement. The factory wiring on my 91 wasn't tinned and the terminals were pretty sad after fifteen years.

Craig

[Rick Johnson]

Ron and Craig.  Thanks! That's what I was asking.  I figured that I needed to upscale my cabling because of moving my starter battery forward.  I was thinking that Ron had suggested #2.  Then, I got this great deal on eBay on some marine #1 (bad idea).  The cables I bought were too short by 2 1/2 ft (but hey, it was cheap) but now the idea of #1 cabling was stuck in my head.  I ran by the boat tonight and there is no stinking way that 2 - #1 cables (starter and ground) and the existing #4 (to the 1-2-both switch) will all fit.  It does look like I can run 2 - #2 cables and the existing #4. 

I know I have asked a ton of questions during this project and I would like to thank everyone for their help!  Moving to Texas has involved a huge number of changes and my C34 represents a large part of my income (and fun).  I like to upgrade what I can, but need to make sure I do it right the first time and spend the money wisely.  I would particularly like to thank Ron Hill who was offered good advice on many occasions and sold me one of the best upgrades yet (Hood 900 SL line drive drum).  Jim Moe was also nice enough to help answer my questions, even when I asked the same question two different ways.  To those who are unhappy with my questions or postings, I will try to limit them in the future and will take the advice to join the C36 group instead.

[Craig Illman]

Rick - Geez, like they say in school, the only dumb question is the one you don't ask!! You just have to accept that most of this boat stuff approaches religion and pick what's best for you and your situation. I think the bottom line is that the more you know about your boat, the safer you are. While not quite as dramatic as aviation, I still think we're dealing with three dimensions and if something goes wrong, you can't just pull off to the side of the road and call AAA.

In the two years I've owned my boat, I've had a lot of enjoyment participating in this forum, using it to research, plan and prioritize improvements to my boat. I don't plan to stop adding my two cents to some of these threads just because someone has a different opinion. I hope to continue to have an open mind and stay willing to be educated from other's experiences.

Craig

[Ron Hill]

Rick : Sometimes a bargen is more of a "pain" than it's worth! 
When I said "the size of the cable you need", oversizing cable is a great example.  Have you looked at the price of #1 connectors and how you're going to crimp them??  Cable #0 size is some big stuff and as I kid one of our Fleet members "now you can start your upgraded 8 cylinder 1230 HP (M25XP?) engine"!?!

Another example of a bargen is many years ago, C34 friend got a 60 amp ferro resistant shore power charger at a "lark"!!  It weighed a TON and generated enough heat to fry eggs on!  So select your BARGINS carefully. 

A thought.   
 

[Stu Jackson]

When we did our alternator upgrade, we were "furnished" an over-sized cable from a friend (for no cost).  It was a tad too short.  We popped in a butt connector with a short extra length of wire, and it's fine, and saved us big bucks.