Welding Cable - Any Downsides when used for Starter Motor???

[Wotname]

What are the downsides of using welding cable for starter motor wiring?

Apart from being un-tinned and possibly different insulation characteristics, I am hard pressed to think of any others but maybe I am missing something.

The question arose after I searched for 70mm2 (~0 AWG) 'marine cable' for redoing the starter motor wiring for a friend.

It seems the Aussie suppliers do not stock anything greater than 50mm2 (~2AWG) in tinned copper marine cable. Anything bigger is welding cable (un-tinned and more flexible). Further researched suggest all the 'bigger' engines around here use it. The existing wiring is welding cable but after 35 years, it is getting dodgy.

I could just use two conductors of 50mm2 but that introduces other issues so right now, I am planning to go with the local flow and use welding cable unless you guys know something I don't.

The starter motor in question draws around 500 amps and the duty cycle is perhaps 5 seconds in 12 or 24 hours!

[Spot]

I watched a wiring video where (the insulation on) welding wire was found to be susceptible to damage by diesel fuel. It was from Pacific Yacht Systems, cannot find the exact link.

[Hartleyg]

There are big differences in the insulation used on welding wire - neoprene (and similar like "Carolprene", etc.)) are fine in the engine room, but EPDM is not. Unfortunately, EPDM is VERY common nowadays - if the wire comes in any color besides black, it's probably EPDM.

The problem with EPDM is its susceptibility to deterioration in the presence of oil, diesel fuel, etc.


Otherwise, just make sure your joints are properly sealed (adhesive-lined heat shrink, etc.) and welding wire works fine. My preference with welding wire is to crimp, solder then heatshrink (belt & suspenders approach!).



Hartley
S/V Atsa

[capt jgw]

Yes, tinned boat cable is better at maybe twice the price, but a lot of boat builders use welding cable and their buyers rarely have any problems with it. I'm on my third boat now that came with welding cable and it's worked fine. No excessive corrosion, degradation of the insulation, etc. If I were rewiring I'd probably use it again. The good stuff can be gotten from places like Genuine Dealz (they sell on eBay) for less, maybe not much more than welding cable. I haven't really compared the prices. When I hooked up my windlass it was more convenient to just order from Genuine Dealz than to source welding cable so I didn't compare.

[smac999]

I've seen welding cable with the sheath completely removed for about a foot due to a leaking fuel line. the bare metal pos and neg unfused battery cables were less then an inch apart... luckily they were clamped seperatlly one above the other to the wall, and not together.

[CharlieJ]

@Wotname
Other than the insulation is not rated for the environment in the engine room and the ultra-fine stranding will wick moisture like you wouldn't believe if there is a breech in the insulation or at the crimp; no problem at all.

I have removed many, many feet of 1/0 welding cable from Taiwan built 1970/1980's vintage trawlers with breeched insulation in the middle of a run, water damage, etc.

And, if there is any concern about adhering to Standards, welding cable does not comply with the ABYC (voluntary compliance) or the ISO (law) standards.

[mike d.]

If you have the room, why can't/don't you cover the welding wire cover with another material not, or less prone to degradation ! That being said our battery cables are 41 yrs young and still going strong, inside engine compartment !

[witzgall]

ABYC does not approve the use of welding cable in any use on a boat. The reason is the insulation is NOT resistant to damage from fuel and oil. You can get a big mess in a hurry if fuel or oil melts the cable insulation away. It is just not worth the risk.

Chris

[Cheechako]

Bottom line is Welding Cable has been used by boaters for several decades. Welding cable is intended to be dragged across dirty floor and sharp metal pieces, wearing far in excess of normal boat routing use. If 3 or 4 decades of use for your starter is good enough then use it. If I have diesel or gas floating around in my boat I have bigger issues than cable type.

One questions if you need that big a cable for a starter though? and whether just marine cable wouldn't be easy and fine.

[witzgall]

So if you develop a fuel leak, the insulation dissolved, the cable shorted resulting in a fire, the I suppose you are right you have bigger problems.

Standards like this are designed to keep people and equipment safe even when the improbable or unthinkable happens. I am not an ABYC zellot, but I think it is reckless to suggest something like welding cable is safe, because it has worked for you and some others. There are many newbie boaters here on the forum, and they may take this as gospel, make a few install errors -- and bingo we have a bad situation. We have all made installation errors and mistakes. Why not use parts that mitigate the effects of said mistakes to keep us safe?

Originally Posted by Cheechako

Bottom line is Welding Cable has been used by boaters for several decades. Welding cable is intended to be dragged across dirty floor and sharp metal pieces, wearing far in excess of normal boat routing use. If 3 or 4 decades of use for your starter is good enough then use it. If I have diesel or gas floating around in my boat I have bigger issues than cable type.

One questions if you need that big a cable for a starter though? and whether just marine cable wouldn't be easy and fine.

[Cheechako]

Originally Posted by witzgall

So if you develop a fuel leak, the insulation dissolved, the cable shorted resulting in a fire, the I suppose you are right you have bigger problems.

Standards like this are designed to keep people and equipment safe even when the improbable or unthinkable happens. I am not an ABYC zellot, but I think it is reckless to suggest something like welding cable is safe, because it has worked for you and some others. There are many newbie boaters here on the forum, and they may take this as gospel, make a few install errors -- and bingo we have a bad situation. We have all made installation errors and mistakes. Why not use parts that mitigate the effects of said mistakes to keep us safe?

While I agree with what you are saying, the bottom line is we make tradeoff decisions all the time. I'll bet dimes to donuts having propane on board is far more risky than welding cable. 1 or 2 boats seem to explode each year here locally from propane or gas issues. Welding cable is very rugged and no, the cover won't "melt and disappear" with a splash of oil or diesel, much less a drop or two.. It may soften over years.

[Cadence]

Originally Posted by Cheechako

Bottom line is Welding Cable has been used by boaters for several decades. Welding cable is intended to be dragged across dirty floor and sharp metal pieces, wearing far in excess of normal boat routing use. If 3 or 4 decades of use for your starter is good enough then use it. If I have diesel or gas floating around in my boat I have bigger issues than cable type.

One questions if you need that big a cable for a starter though? and whether just marine cable wouldn't be easy and fine.

on the bigger issues.

[OS2Dude]

People (& manufacturers) have done a LOT of silly things 'for decades', doesn't make it the smart thing to do. ISO and AYBC both say NO, so take the hint.

Items that affect the safety of the boat and/or crew are not the things to cheap out on.

I read a good article somewhere that experience is actually a lousy teacher. The person who gets away with drinking and driving, or texting and driving, or any number of stupid/illegal activities thinks they can 'handle it' because their experience has taught them so. Right up to the moment someone gets hurts/dies. . .

[Jono as 2234]

Was bringing a very old, poorly maintained wooden ketch back to Sydney from the reef, for a refit. Off Newcastle the welding cables in the engine room shorted from Diesel damage and we had a fire. The op had stored paint in there, so a bit of panic ensured. The boat was an old Bass Strait fisheries patrol boat. Op had a trailer winch on the mast for the main, and the bilge pump was a $20 special we lowered into the bilge on a bit of wire. I guess there are weldng cables and welding cables.

[Thumbs Up]

Look up Locomotive cable