65beam
Donation Time
I'm a gambler. What are the odds of dropping a screw driver on the battery considering it's in a covered box behind the seats?Jerry, Me being a dummy, I can appreciate your rant
Thanks for the advice....and the warning!
-
Welcome to the new SAOCA website. Already a member? Simply click Log In/Sign Up up and to the right and use your same username and password from the old site. If you've forgotten your password, please send an email to membership@sunbeamalpine.org for assistance.
If you're new here, click Log In/Sign Up and enter your information. We'll approve your account as quickly as possible, typically in about 24 hours. If it takes longer, you were probably caught in our spam/scam filter.
Enjoy.
Wiring Harness Recommendations
- Thread starter DaisyPusher
- Start date
DanR
Diamond Level Sponsor
Bob, I don't believe Jerry was referring to "dropping a screwdriver", probably more like maybe using one to jump across the see if the battery was hot!!! I'm known of folks doing such stupid things
And of course, in the event of accidentally having the posts make contact any time, the fuse would and could prevent what he was attempting to forewarn!
And of course, in the event of accidentally having the posts make contact any time, the fuse would and could prevent what he was attempting to forewarn!
Not a rant, just good advice. There were quite a few of my customers who installed a 60 amp fuse as per your suggestion. Thanks for all your good common sense advice. PeteOne additional comment on this. Fuses are all about the concept of "Safe Failure" - When something goes wrong in the system a fuse should blow open instead of a wire melting and the resulting fire.
In this particular situation, for ALL Sunbeams, new or old wiring harness, this means that you should be able to short any wire to ground at any location in the car, and the worst thing that happens is a fuse blows.
For the above reason, this is why I suggest the 350A inline fuse back near the battery. That protects the battery cable from the battery up to the starter solenoid, if it chafes through and grounds out. 350A is plenty to crank the engine (original 4 cylinder or the V6) - At some point you might make the mistake of shorting a screwdriver across a battery, and a typical car battery can put out 600A (or more) and melt the screwdriver. (been there done that)
In addition, I suggest the 40-60A inline fuse in the wire that goes from the Battery side of the starter solenoid, to the ignition switch. because this wire, and the Run power, and accessory power wires from the ignition switch are not fused either. Full battery current is available on all of those wires.
Those two changes should be introduced into all cars, new or old wiring harnesses.
Rant over!
loose_electron
Donation Time
The comment about melting the screwdriver across the posts of the battery is to illustrate the amperage available from the battery.
Your problem area is that long cable directly connected to the positive post of the battery. If that cable chafes through to the frame of the car anywhere that's the issue. The fuse, in line with the battery, right near the battery, makes this situation a lot safer.
loose_electron
Donation Time
One other piece of information -
The high amperage fuse in line with the battery is not seen in most modern cars, because of the fact that the battery cable to the starter solenoid is very short and the battery is close to the starter.
If you look at aircraft and boats, where the batteries have longer high amperage cables coming off the battery, this is a widely observed safety practice.
https://www.pbase.com/mainecruising/battery_fusing
Above is how it's done in boats.
The high amperage fuse in line with the battery is not seen in most modern cars, because of the fact that the battery cable to the starter solenoid is very short and the battery is close to the starter.
If you look at aircraft and boats, where the batteries have longer high amperage cables coming off the battery, this is a widely observed safety practice.
https://www.pbase.com/mainecruising/battery_fusing
Above is how it's done in boats.
This reminds me that I never updated the group on my experience with a master fuse discussed in a previous thread (http://forum.sunbeamalpine.org/index.php?threads/replacement-wiring-harness.27508/). We had some discussion about what 1.0 gauge wire was vs stock wiring. It took a gamble and bought the fuse. Here is a photo of the wire that came with it, sitting next to the stock wire. A pretty big difference. I need to figure out a good way to connect the stock wire to the fuse holder
.
.
loose_electron
Donation Time
I used an ANL fuse holder for the battery:
https://www.ebay.com/itm/1-Waterpro...767006?hash=item1cb969405e:g:sE4AAOSw~kVbm7AR
Similar to the above. Hid it under the car right where the cable leaves the battery box.
There are other solutions out there too.
65beam
Donation Time
Dan,Bob, I don't believe Jerry was referring to "dropping a screwdriver", probably more like maybe using one to jump across the see if the battery was hot!!! I'm known of folks doing such stupid things
And of course, in the event of accidentally having the posts make contact any time, the fuse would and could prevent what he was attempting to forewarn!
He said it but common sense would tell you not to do it. It's hard to find a group 24 battery that matches the original battery that the battery hold down will fit over. I do have the hold downs but I choose to only use them if the cars are in a show where judges may look for them. I glue a rubber matt to the underside of the battery box lid on my cars. There are subtle ways to eliminate potential problems without re engineering the car including the proper use of grommets and the tabs under the car to secure the battery cable in the original locations. I use a rubber sleeve over the cable where secured by the tabs. My battery cables are made using a #4 cable I buy at O'Reilly's. It's flexible and easy to use. At one time someone mentioned quick disconnect cable ends for the battery. I bought a set just to see what they were and they're an accident waiting to happen. Anybody want them?
Last edited:
65beam
Donation Time
Because they will not fit the terminal posts of a group 24 battery. The inside diameter of the clamp is less than the outside diameter of the post. Have you ever tried to fit a 5/16 inch bolt thru a hole intended for a 1/4 inch bolt? Doesn't happen!That would be me.
That wouldn't work. Mine fit my group 24 battery just fine, but they are more than 20 years old.
A lot of battery clamps will spread or otherwise accommodate both battery
65beam
Donation Time
Bill,
The group 24 is what I use in all of our Beams. The problem is that these clamps are not your normal battery clamps. They're quick release clamps . There is no way to expand them to fit over the terminals. Haven't tried them on the small Craftsman tractor battery. When opened to hook them to the terminal they actually get smaller in diameter.
The group 24 is what I use in all of our Beams. The problem is that these clamps are not your normal battery clamps. They're quick release clamps . There is no way to expand them to fit over the terminals. Haven't tried them on the small Craftsman tractor battery. When opened to hook them to the terminal they actually get smaller in diameter.
Charles Johns
Donation Time
1789, Bad Grounding is probably the most common car electrical problem. I wire my cars from scratch then make a schematic so I know where things go at a glance. AND like you, I make sure things are well grounded.
Charles Johns
Donation Time
I plan on putting a 24 battery in the stock position behind the pass seat, but change the lid from metal to plastic or fiberglass. My only fear of a problem is being unable to quickly disconnect it if a need arises. Because I wire my cars the big battery wire is always a major safety issue. Keeping it out of danger is a main consideration. This fuse idea sounds like an answer.
DanR
Diamond Level Sponsor
Charlie, I like the original battery box metal cover and especially like the quick disconnect locking device. Do you still have the "locking" device with the O ring ? Do you have the battery strapped down?
The metal cover will withstand most abuse even if you should stand on it whereby I don't believe a plastic one would do the same.
I think another method of security could be a piece of rubber sheet underneath the cover.
The metal cover will withstand most abuse even if you should stand on it whereby I don't believe a plastic one would do the same.
I think another method of security could be a piece of rubber sheet underneath the cover.
puff4
Platinum Level Sponsor
That’s what I’ve got under mine... put it there 30 years ago.
loose_electron
Donation Time
The rubber sheet glued to the bottom face of the metal cover is what I did. Gets it done. Fiberglass would be a yet safer option. I don't think most plastic (without glass/carbon/kevlar fiber reinforcement) would be suitable.
Charles Johns
Donation Time
When I said "plastic" I referred to some black heavy-duty stuff I have, probably more like Lexan. My battery cover is bent/bowed like many and I may do the rubber glued on bottom idea. The idea of a "Fail-Safe" device in the main supply on a daily driver hits my HOT button. YES, with Air, Cruise, Stereo, Overdrive Automatic, and insulation to make it quiet, I may make it a regular use or even daily use ride. If I do that, my "spares car" will be a keeper...just in case.