How to make a cheap isolated dual-battery setup for $50
- Thread starter evldave
- Start date
dwh
Tail-End Charlie
Try this, might be close...
http://www.ttguide.net/checking_and_replacing_fuses-143.html
Couple of possibilties I see...
Engine compartment fuse box:
#7, seat heaters. Do the seat heaters work with the key on ACC or only when the engine is running (or key turned to run)?
#9, trailer battery charge. Again, does it only work with the key to on or engine running?
Under dash fuse box:
#15, wipers. Do they work on ACC?
http://www.ttguide.net/checking_and_replacing_fuses-143.html
Couple of possibilties I see...
Engine compartment fuse box:
#7, seat heaters. Do the seat heaters work with the key on ACC or only when the engine is running (or key turned to run)?
#9, trailer battery charge. Again, does it only work with the key to on or engine running?
Under dash fuse box:
#15, wipers. Do they work on ACC?
Here are the photos of my engine compartment fuses. Nothing there that I can use the add-a-fuse dohicky. I've decided to use the cab fuse box, connecting to the ignition fuse. (I did have lots of other choices in that box that were hot when the key was "on" but off when the key was on "aux".)
To pass the 14 gauge wire through the firewall to the isolator, I'm hoping it's OK to just poke it through the big rubber grommet that the wire harness passes through. I tried threading it next to the harness, but the way the boot works, that would thread it into the cable protector, hiding it from me. I figure a little round hole punched through and "sealed" with the wire won't compromise the sealing property of the boot. Please tell me if I'm wrong.
To pass the 14 gauge wire through the firewall to the isolator, I'm hoping it's OK to just poke it through the big rubber grommet that the wire harness passes through. I tried threading it next to the harness, but the way the boot works, that would thread it into the cable protector, hiding it from me. I figure a little round hole punched through and "sealed" with the wire won't compromise the sealing property of the boot. Please tell me if I'm wrong.
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scott7022
Nobody
Punched through a ton of rubber grommets that way without issues. If you're worried about water save that part till the end of the day. Pull your wire, add some silicon to it, pull it back and forth a bit, in the hole. Add a little more silicon engine side and go to bed. Let it dry overnight.
Help! Crimping issues
I'm finally diving in and immediately ran into trouble. I purchased a 16 ton hydraulic crimper and ran a couple test crimps. Using the #25 die, the wire slips right out. After the dies met, I cranked down another 1 1/2 pumps, where I didn't feel I could go any more. I was worried I'd pop the seals. Dropping down to the next smaller die size in the kit, #16, wings form on the crimp, indicating an over-crimp. What's faulty, the die, the wire, the terminals, or me? Here's what I bought:
4 aug all-copper, made in the USA welding wire - Ebay
Conductor Size: 4 AWG
Feet Per Pound: 6.8
Stranding (qty. x dia): 364 / 30
Nominal O.D. (in.): 0.331" (I thought that was the width of the conductor, but it includes insulation; the diameter of the copper is about 1/4")
Conductor Material: Copper
Approvals: NEC article 630 electric welders, Meets SAE J1127 and ASTM B-172 standards. RoHS Compliant.
I'm using FTZ starter lugs from Marine Bay. The diameter of the interior is about 5/32." The metal is not very thick.
NOTE: Most of my connections will be made with the FTZ lugs but I'll also be installing a set of Anderson quick disconnect terminals. They have an interior that is close to 5/16" and the metal is much thicker. I don't have any extras of those.
I'm finally diving in and immediately ran into trouble. I purchased a 16 ton hydraulic crimper and ran a couple test crimps. Using the #25 die, the wire slips right out. After the dies met, I cranked down another 1 1/2 pumps, where I didn't feel I could go any more. I was worried I'd pop the seals. Dropping down to the next smaller die size in the kit, #16, wings form on the crimp, indicating an over-crimp. What's faulty, the die, the wire, the terminals, or me? Here's what I bought:
4 aug all-copper, made in the USA welding wire - Ebay
Conductor Size: 4 AWG
Feet Per Pound: 6.8
Stranding (qty. x dia): 364 / 30
Nominal O.D. (in.): 0.331" (I thought that was the width of the conductor, but it includes insulation; the diameter of the copper is about 1/4")
Conductor Material: Copper
Approvals: NEC article 630 electric welders, Meets SAE J1127 and ASTM B-172 standards. RoHS Compliant.
I'm using FTZ starter lugs from Marine Bay. The diameter of the interior is about 5/32." The metal is not very thick.
NOTE: Most of my connections will be made with the FTZ lugs but I'll also be installing a set of Anderson quick disconnect terminals. They have an interior that is close to 5/16" and the metal is much thicker. I don't have any extras of those.
What do you expect from such a cheap crimper?
They are metric dies, not quite matching up with US weird imperial.
And won't last long if used much.
http://www.pbase.com/mainecruising/wire_termination
http://www.pbase.com/mainecruising/battery_cables
https://forums.sailboatowners.com//index.php?threads/crimper-shoot-out-load-test-results.125926/
https://www.google.com/search?q=maine-sail+crimp
If you're patient and good at eBay sniping, you can pick up the proper tools for 10% their new value, but will still be $100s, just not thousands.
Or best of all just get genuinedealz.com to make it for you custom.
Resolved
I also purchased some different lugs before I read that the FTZ lugs were excellent quality and combined their purchase with other things I was ordering. I just did a test crimp with these other lugs and the crimp held fast. Apparently, the FTZ lugs are made of thinner gauge metal.
On to the next step.:wings:
I also purchased some different lugs before I read that the FTZ lugs were excellent quality and combined their purchase with other things I was ordering. I just did a test crimp with these other lugs and the crimp held fast. Apparently, the FTZ lugs are made of thinner gauge metal.
On to the next step.:wings:
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Hillbilly Heaven
Explorer
I like the thick wall tinned copper lugs. They crimp much better.
I only need them for a dozen lugs.
That article is what led me to order the FTZ lugs, but I didn't read carefully enough. It said "heavy duty" so I thought I was getting the Power lugs...but it turns out, they were starter lugs.
Too much for me to spend for a dozen lugs.
I imagine that would be just, or more, expensive that the cheap tool and would be harder to ensure the lugs were oriented correctly to avoid twisted cable on short runs. I also wouldn't get the "joy" of learning more about electricity and just how the stuff I own - and may need to troubleshoot - works.
I think they charge very fair pricing for the materials - definitely top quality, no research/guessing required.
And I believe the charge per crimp is $1
Their sister site http://www.bestboatwire.com sells the supplies in bulk, including Pacer Group marine wiring, as good as but much more reasonable than Ancor.
And I believe the charge per crimp is $1
Their sister site http://www.bestboatwire.com sells the supplies in bulk, including Pacer Group marine wiring, as good as but much more reasonable than Ancor.
Thank you for the information. Now if I could only go back in time...
I'm not sure what makes these lugs "heavy duty." They seem anything but. A knock off?
patoz
Expedition Leader
The Starter Lugs you have are the light duty ones. These Power Lugs are the heavy duty ones. Look at this link and scroll about half way down the page.
another_mike
Adventurer
I know you claimed to have read this page, but you need to keep rereading, many of your mistakes and questions are already answered in it http://www.pbase.com/mainecruising/battery_cables
It goes into adequate detail the differences between a power lug and starter lug. He also was able to make a successful crimp on a 4 awg wire and a heavy duty lug with the harbor freight tool albeit not using the die for "4 AWG". Now you just have to hope the cheap harbor freight quality control isnt so far off that you get the same result.