Replacing old (original?) engine to main battery earth cable (1 Viewer)

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Toronto, NSW, Australia
I've been working on a replacement for my 80's primary engine earth cable linking the neg terminal of the main battery direct to the connection point at the bottom of the 1hz engine block. This is what the end fixed to engine looked like until I took it off yesterday:



pic page

The bolt is a short M10 fine thread (not sure yet of exact pitch) with a 14 mm head. The big washer is captive to the bolt.

I had an aftermarket new battery lead with a straight (not 90 degree) lug so have worked that up into a substitute while I source some 25 mm sq welding cable and suitable lugs to make up a proper replacement.

I cannot work out from any of the 80 series part listings what the factory p/n is for the bolt or the main cable to the battery, or for the main cable from battery + to starter motor, but all of those can be replaced with custom-made cabling. Welding cable is very flexible so good to work around other stuff but normal high-current AC mains cable as used in industrial sites, mines, etc. probably works just as good.
 
Too bad you are in AUS. I have plenty of those 90º lugs, especially if you are running 1/0. If the bolt is M10 then its 1.25 pitch.
 
Electrical mains cable is very different. It's made up of less, thicker stands of copper. It's far more rigid and less able to cope with the vibrations it would be exposed to in an automotive application. Copper work hardens becomes brittle when its bent back and forth. Vibrations and engine movement can be enough to cause this. I had '70s era cars that had battery leads made with coarse copper strand cabling, failure through work hardening was a problem.

Welding cable is a good option
 
Electrical mains cable is very different. It's made up of less, thicker stands of copper. It's far more rigid and less able to cope with the vibrations it would be exposed to in an automotive application. Copper work hardens becomes brittle when its bent back and forth. Vibrations and engine movement can be enough to cause this. I had '70s era cars that had battery leads made with coarse copper strand cabling, failure through work hardening was a problem.

Welding cable is a good option
The OEM cabling is pretty coarse for what its worth. Thin jacketing too.
 
I've used welding cable before and over time I wasn't pleased. When I cut into it, it had wicked up moisture. As usual, I think NLXTACY is right, marine cable. Not only is the jacket better for this application, the strands are tinned for improved weatherproofing.
 
Just make sure your crimps are good and just about anything will be fine. Nothing wrong with welding cable if done well, it will definitely be better than stock.
 
NLXTACY is absolutely correct on this. I researched battery cable in aid of replacing the leads in my truck with the correct stuff. Here in the States, there are a few different cable grades that comply with SAE specs. Grades SGT and SGX are the most common. Welding cable is not designed for oil and grease resistance. Neither is it designed to withstand engine compartment temperatures. SGX cable is designed to tolerate higher temperatures than SGT, and the price is about the same.

I used #2 cable because that is what Mr. T used when he built my truck. I wish I had used #1. Nowadays it seems the lug manufacturers are phasing out products made specifically for #2 wire. They label the #1 lugs as suitable for use with either #1 or #2 wire. High end lugs are (or are supposed to be) marked with 3 bits of information on each lug: 1)The size of the wire the lug is designed for. 2)The size of the hole to accommodate specific post sizes i.e.1/4",5/16",3/8". (Using a larger hole on a smaller post is considered bad practice. Match them correctly and be happy). 3)The letter designation of the correct die size to utilize when crimping the lug to the wire. There is a lot of space left over in the #1 lug's wire cavity if #2 wire is inserted into it and it makes for a sub-optimal crimp. I do not know if the connection is sub-optimal (yet), but it looks like hell. To me, if something does not look right, it probably does not work right. More info on crimp tools below.

When buying lugs be aware that there is a bewildering array products out there, some of which are not designed for automotive applications, and may not crimp properly if you use them. The heavy duty "Power Lugs" are the highest quality and are the most expensive.Your local electric supply or home center is NOT the place to buy this stuff, unless they sell products specifically for auto and marine applications. If you buy lugs from your local auto supply, be aware that those products are generally of low quality, being made of thin metal to (probably) imaginary standards. Marine supply stores seem to have better stuff than the auto supply houses. Buy the tinned copper lugs (silver in color) as they resist corrosion better than bare copper. Use adhesive backed shrink wrap as it produces a more water tight seal than non adhesive backed.

The amount of ignorance on the part of the salespeople in this industry is absolutely appalling, as is the avalanche of internet B.S. on the subject. I am no expert on the matter but I have spent considerable time in a rather vain attempt to figure it out. Some of what you are reading here comes from my mistakes and depleted pocketbook. You may want to avoid components made in Mainland China. From what I have been able to discover, the Chinese stuff looks viable, but is manufactured to no standard known to god, God or man. Then again,even the U.S. made products may not be made to any universal standard.I suggest buying components manufactured in the U.S. (or possibly another outpost of Western Civilization) exclusively if you want top quality, but be aware that each manufacturer may have their own crimp die size standards. The best practice may be to buy a crimping tool made by the same outfit that makes your lugs, if possible.
Quick Cable and FTZ are U.S. manufacturers that make this stuff.

So far the best place I have found to buy quality components Stateside seems to be Del City (www.delcity.net) . I have their print catalog, and on the pages where the lugs are listed, a suitable crimping tool (that they also sell) is listed for each lug.

BE CAREFUL WHAT YOU ORDER AND FROM WHOM YOU ORDER AS THE RETAILERS MAY UNKNOWINGLY SUBSTITUTE CHEAP JUNK FOR THE QUALITY STUFF YOU THINK YOU ARE ORDERING! IT MAY BE BEST TO PLACE YOUR ORDER OVER THE PHONE SO YOU CAN ASK DIRECTLY. Be not surprised if they get annoyed with you for asking about the quality of their merchandise. They probably have no clue as it all looks similar. Anything I order from here on out will be of a specific brand, probably Quick Cable, with no substitutions tolerated.

Proper, U.S. made crimping tools for large wire, battery applications are ruinously expensive. We are talking somewhere in the neighborhood of 1500 smackers for a tool that looks like a pair of medium sized bolt cutters! There are power crimpers that look like cordless drills which cost around 3 grand! A set of the interchangeable dies for the power tools costs over a thousand bucks!
Del City carries Asian import tools (possibly made in Taiwan) that are under $500.00, some with interchangeable dies.
Harbor Freight and Amazon carry hydraulic tools that all look to have been made in the same (expletive deleted) factory in China. These generally cost less than a 100 bucks. As usual, the 5 star ratings are best ignored. Pay studious attention to the one star ratings which tell rather a sordid tale.
For a low BS review of the HF offering, google "Compass Marine" and/or "How to make Your Own Battery Cables". (Haven't yet figured out how to post a link) Much of the info I relate here is from this article. I do not agree with his assessment of the FTZ crimping tool however. I bought it on the strength of his recommendation before discovering Del City. It is not as versatile as I want. Sometimes I have found it necessary to improvise crimp die settings as the lugs do not always crimp right even with the die settings specified on the lugs. "A little bigger' or "a little smaller" is extremely difficult to do with this tool.

These are the facts as far as I know them. If I have erred in any particular, please post a correction. If you are "in the know" on this subject, kindly expand on these comments.
 
Awesome range of replies so thanks everyone.

Yes it's difficult to get through the minefield of lug options but I'm getting there.

I didn't think about 'marine' grade high-current power cabling vs normal welding cable. The reason I looked at welding cable is that it's very flexible fine-stranded so going to far better handle vibrations/movement. Plus most of it is double-insulated.

The cable I used to replace the factory earth lead isn't 'mine spec' type quality but it's doing the job temporarily.
 
His article on "Marine Wire Termination" is a triumph of bedtime reading, besides being super informative. That package of Harbor Freight terminals that includes the (expletive deleted) crimping tool you bought because it was cheap will be on it's way to the round file as soon as you regain consciousness...
 
His article on "Marine Wire Termination" is a triumph of bedtime reading, besides being super informative. That package of Harbor Freight terminals that includes the (expletive deleted) crimping tool you bought because it was cheap will be on it's way to the round file as soon as you regain consciousness...
It is some heady stuff, for sure. Especially because I don't know anything about boats beyond that they are about as healthy for your wallet as a gambling problem is and I just am too much of a tightwad to be a boat owner.

I built up a boat with the principle that I would spend $0 and figure out a way to get a boat. It only took a couple of months and I wore a guy with 3 DUIs down from five hundred bucks to no bucks and then I patched together a motor and some oars and tried to get excited about boating, but I think I am already just too far down the canoeing path to enjoy it.

My boat is for sale at the moment, just as a side bar. She's a trusty sloop, I will give her that...

https://duluth.craigslist.org/boa/d/14-aluminum-boat-trailer-with/6612347750.html

That will probably be my last boat unless I can find something simple that I can use on the big lake for cheap. I have a line on a FJ62 that I might part out and build a little fund with. Probably not a boat fund though.
 

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