Took the truck for a spin yesterday and all was well for the first few stops. Went to get gas and when I went to restart the starter cranked for a couple of seconds and then sounded like it was jammed or not really turning. So I pushed out of pump area tried again and it would crank for a couple of seconds and then the noise. Looked in the engine compartment and the main line from the battery was smoldering and wire was visible. Had it flat bedded home and when I tried again it started like normal. I assume the resistance went up due to the poor condition of the line, which caused hi amperage. I plan to replace all the wires and ground straps and clean all connections. Anyone think I should be doing anything else?
Battery Cables When you replace them , you'll have to special order the correct 1 or 0 gauge ones as that's a 4 gauge . Also , the ground cable *MUST* be connected to the transmission or engine ! you MUST NOT attach it to the frame . Then , I'll cover the other issues but first , the correct battery cables .
thanks I ordered the wire from our sponsor, assumed it would be correct guage. I will attach as you suggest, thanks.
Never ! Assume anything that's what these forums are for ~ clarifiying how to do things right and easily .
guage I checked with classic parts and their battery cable is 2 guage, which I had already ordered and they have shipped.
I had Brad in our parts department do some research on the situation and here is what he found out. "After talking to American Autowire the only way a cable will melt is if it is hooked up backwards or it is continually cranked from a non starting situation. This draws so much current it will over heat. The correct gauge is 2 gauge and if a 1 or 0 gauge is used the truck will be very hard to start as it takes too much current. We sell the correct gauge and have been for years with no problems. Thanks Brad S. Research and Development for Classic Parts" The 43-412 cloth covered and the 43-413 rubber covered cables we sell are both 2 gauge. Adam
I'm on board with Bill...the larger the conductor, the less resistance and the more amps it can handle. I believe that the #2 is probably correct if you are still on a 6V system (as the volts go up, the amps decrease, if your wattage draw/load remains the same), but a #1 or heavier should not adversely effect anything. Thats about all I got to say about that.
Ohms Law I = V / R so if #2 is correct for a 6v system. I have a 12 v system so the amperage will be higher. I found a wire resistance table and 1 gauge is .1265 ohms/1000' and 2 gauge is .1594 ohms/1000' Now what I am not sure is how significant that difference in resistance (about 25%) is in 40 inches of wire? Clearly if one has to crank a long time amperage will be significant. However my truck starts nearly instantaneously. So my plan, since the 2 gauge has shipped is to replace all wires/grounds, clean all terminals, and see what happens. If you think this is a mistake please let me know. Anyone have a source for 0 or 1 gauge?
resistance calculator I found an interesting website for wire resistance. see http://www.cirris.com/testing/resistance/wirecalc.html This site shows no difference in resistance for 1 and 2 gauge at 40 inches. I am sure there is a difference but the test will be is there a practical difference. Hope to get my parts today and install. Denis
Brad S. in our Research department received this information directly from American Autowire which is a manufacturer for some of our battery cables. They also produce complete wiring harnesses for these old trucks. Adam Classic Parts of America
Sadly , This just means yet another cheapo supplier that isn't interested in doing things correctly , just for maximum profit . " if a 1 or 0 gauge is used the truck will be very hard to start as it takes too much current. " ~ this boggles my mind , 7th grade science failed . "After talking to American Autowire the only way a cable will melt is if it is hooked up backwards " ~ so wrong it is scary .
7th grade science failed You must have been a bad student Nate, if I remember right, you also failed 7th gade math!
How does one hook up the battery cables backward? Just saying, the ends are quite different..............
A wire CAN get very hot and melt the insulation when a lot of current goes through it. I've done it. It also melts quickly when grounded out. Too big a wire won't cause issues, but too small can.
Backwards Battery Cables When you get into Marine , Bus or Heavy Duty applications , the battery cables often have ring terminals on each end . I always solder the ends on , maybe American Autowire thinks that's bad too ? . I'm having much fun repeating the silly claims made by them , the Journeyman Mechanics are rolling on the shop floor pi$$ing themselves with laughter . BTW : a # 2 gauge cable is fine for a 12 volt system , I just prefer my vehicles to roar into life with maximum cranking speed using minimum battery reserve , by using # 1 or 0 gauge cables . For a hobby truck in a heated garage I suppose any old thing is O.K. but I work my vehicles , every one of them so instant starting in 125° F heat or sub 0° temps , is important to me . I also never have to rebuild starters because they don't wear out if your engine cranks so fast it always starts in one or two revolutions .
