DEAD BATTERY?

66Sprinter

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My battery keeps dying. I have a FORD one wire alternator and it was hooked to the start solenoid. (Battery dies in a week)
Then I added a two post cutoff switch and put the alternator 1 wire on the starter side of the switch to keep the battery from draining and just in case the diodes in the alternator are faulty and starts a draw.

I have heard that you are supposed to put the alternator wire on the (+) side but I haven't yet. I don't need the kill swtich for racing, just normal storing. This whole thing was to allow me to cut off the battery so it wouldn't drain. Seems like I made it worse? Any thoughts?

Last time I drove it...the battery went down to 8.1 volts and my tach was running backwards :roll: Jim
 
Well that's a simple fix you have two options.

A: Wire it correctly

B: Put in a Battle switch and shut off the power to the battery when it sits.
 
I am confused about what you're doing, but the charge wire from the alternator needs to go as directly as possible to the battery positive terminal (and that usually happens via the starter solenoid) and the sense wire from the alternator needs to go to an ignition-switched source (and that often happens on the other side of the GEN/ALT light). That is the correct and only way of installation an alternator.
 
thesameguy":py21d7cs said:
I am confused about what you're doing, but the charge wire from the alternator needs to go as directly as possible to the battery positive terminal (and that usually happens via the starter solenoid) and the sense wire from the alternator needs to go to an ignition-switched source (and that often happens on the other side of the GEN/ALT light). That is the correct and only way of installation an alternator.

One wire alternators have no excite circuit and do not require a switched source. What your doing is not confusing but more than likely it is just a band aid and if you want to solve the problem you need to perform a few tests. First remove the alternator and have it bench tested. If it checks OK, check for shorts or draws on the battery by connecting a simple test light between the disconnected negative battery CABLE and the negative POST on the battery. If the light glows, you have a draw and you need to find it. You can pull fuses one at a time until the light goes out to narrow down the circuit. Once you have found the circuit, you can look more closely from there to find where it is ie: radio, heater blower, etc... And fix it.

The power wire from the alternator should then then be routed directly to the battery and with a heavy gauge wire of at least a 10 gauge. Let us know what you find. :beer:
 
Which side of the solenoid is the alternator connected to? If you have it attached to the starter side, it won't charge the battery. The solenoid is a switch and there's no connection to the battery from that side of the solenoid. Your car will run on battery power but it will eventually run out of juice.
 
Sorry for the late reply. I was called out of town.
First, before adding the 600v/600A two post switch, I wired direct from the battery (+) terminal to the non starter side of the solenoid. The alternator 1 wire goes there too!. The other side is just one cable to the starter. I am using 8ga

After adding the two post cutoff, the battery POS cable went to 1 side of the cutoff switch by itself. The alternator wire and the lead from the cutoff switch went to the other post. Turn the switch ON and the battery comes in to help the alternator and power the starter solenoid. I have never shut it off wth the car running, suspecting that the engine will continue to run with the alternator still spinning. (I dont have the paperwork for the alternator so I dont have the specs for it) Thats something I need to look at as well as if it has a two terminal (small box) located to run a volt meter in the dash panel if one so desires)

The switch was not intended for a KILL switch but a convience to not having to disconnect the battery for storage. (I travel alot and have always disconnected the battery when I am gone for more than 2 weeks at a time.

This weekend, I am going to rewire it back to where it all started and then setup my meter to check the charge voltage at 1000, 1500 and 2000 rpms. It may be that it won't excite until 2000 and I usually cruise between 12-1800 rpms with my 54 speed. I will post findings. If so then I am sucking the battery for everything and the alternator is not helping at all. (including recharging the battery.)

Be back on Sunday evening for the results. Jim
 
OK..its Sunday night and I am feeling PO'd and about $100 more stupid than yesterday. I purchased this alternator from Summit. SUM-8108308 and its a GM style (internal regulator) with FORD mounting. Its 6 months old (out of warranty?) and up to 3K rpms there is no excitement to start the charging!! So the entire time I have been working on a parasitic drain, it was my alterntor not charging the battery. (Throw in the cost of a new battery too). :rolflmao:

I will get it down to the Zone tomorrow and have them test it..but results should be the same. I wil aso be calling Summit to see if they can help me with this? What a bummer :banghead: On the good side I have rechecked all other wiring hon the car, added two new ground straps and tightened every thing up really good. :roll:
 
Took the Summit alternator to Advance Auto for a check. One wire setup (no way to know RPM's but I suspect 2000) and it checked OK giving out 14.8 volts. So my next assumption is the crank pulley. Does anyone have a dimension for the pulley? Anybody with a L6 pulley off the block they can measure up for me? i do appreciate the help. I can only surmise that the L6 is smaller diameter than the V8..or maybe not. I don't have a spare one to compare it to.
Thanks, Jim
 
You have something else going in here man. The pulley would have to be waaaaayyyyy off in size to not charge at 3000 rpm. And also, yiur cruise rpm doesnt really matter for your charging voltage. Once a wire alternator is excited after starting, it stays that way until the engine is shut off. So even if you had to zing it up to 2000 rpm after starting which is common, it will jump up to the standard charging voltage and stay tickled until it is deenergized after engine shut down. A generator, yes... Very rpm Dependant but not your alternator.

How is the wiring from the alternator to the battery? I have seen crimp-on connectors come loose on the alternator output terminal and still looked OK at a glance but would not pass the current to the battery. If the charging wire disappears anywhere into a harness, remove it and make sure it has not been cut or damaged or that it may contain a blown fusible link.

You can also try a direct jumper wire from the battery + to the alt output while the engine is running to temporarily by pass the in-car wiring. After attaching the jumper wire, goose the throttle to tickle the circuit and if it starts showing proper charging voltage, your problem is somewhere in the under hood wiring.
 
Thanks for the tips guys. I kinda gave up on the pulley change after researching different pulleys from various years and they are not much different than the L6. So I am giving up on that idea.

With alternator installed, I checked alternator case to NEG on battery and had a good circuit. There is only 1 wire from the alternator post to the POS side of the starter soleniod. Doesn't go through any harness. Its #8 gage and crimp connectors are tight. There are two spade terminals on the case. Without a data sheet on the alt. I cant confirm what they are for, although I suspect they are for gages.

Also checked for drains with my meter. Removed all wires from the POS side of starter solenoid and checked each. No tic's at any ohms for any of them. Did not do the bulb test though. Grounds are good, but I may add a ground strap from the case to the frame just for a test.

Called Summit yesterday and they do not have a data sheet for install on the alternator. Would not replace my alternator since I was 14 months old (1yr warranty). CS gal said I had not purchased enough $$$ in the year to warrant special consideration. (That made me feel good!)

Heading to Michigan later this week for work, so I will only have tonight for spare time. Then it sits for two weeks when I return and start over again. Thanks again for all your tips. I do appreciate it. Jim
 
Have you checked the battery's condition? IE did a load test and checked the total voltage at posts. Good luck :nod:
 
Thanks for the tip. I purchased a new battery 4 months ago when I had killed my other one (3hrsold) Again, my bad, but I never suspected that I was not charging while driving. As far as troubleshooting goes, I started at the wrong end and made it worse in time and $ doing things backward.

Now that the alternator has been checked, it goes back on and then I start with the POS post and start testing if the alt. excites and starts the charging circuit. Add the wire between post and solenoid and check again. Its got to be something simple. I may even add a ground strap to the mounting bolt of the alternator to insure a good ground. At the ZONE the alt. was putting out 14.8 which should be good enough while driving. My btty charger puts out 16.2 at FAST and 14.0 at SLOW settings. Most of the time I am tinkering then on the road for a week or two and then back to tinkering again. So now I have to focus and not get distracted. I am gone again next week. My goal is to resolve this by the weekend.

Thanks All, Jim
 
Ok ,if you have in fact got a gm one wire please do not believe it only needs one wire. The two spade connecters need to be attached as well.
the sensing wire that often gets connected to the charging wire at the alternator should in fact run along side the charging wire to its connection point, generaly the selenoid, to read the draw at that point. the other wire should go to your idiot light to let you know if is charging. Look up Delco Remy wiring diagram for schematic on proper wiring and alt identification. Wired the proper way you should start charging immediately when needed without having to goose rpm.
 
The alt he has is a GM 10si style unit. I tend to agree that trying to run a 10si as a one wire is not going to be reliable. I would try wiring it properly as a 3-wire - it's not like there is much involved in doing that.

I don't understand what you wrote here:

Add the wire between post and solenoid and check again.

?
 
I reinstalled the alternator after checking it many times on my bench. After seeing the setup at ZONE, i used my drive belt and hooked it up to my bench grinder pulley and spun it up. 14.8vdc each time for 5 times in a row. So I put back in the car and used a ground strap on the swing bolt and then hooked it up. Started the car and checked 14.5vdc at the POS post of my battery. Hummmmm. I guess you never know what you dont know until you listen to someone else. Early in the post someone mentioned about grounding. That was the reason I added the ground strap. Now its fixed. Works great. I even added my KILL swtich back and all is well in middle earth 8) My thanks to all for your input. My brother tells me that there is no age limit on stupid. I will wear it proudly now that my car is back on the road. :rolflmao:
Thanks again to all - Jim
 
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