Hot Rods One wire Alternator question

Thanks, I will check. Just had shoulder surgery, working one handed takes longer.

 

Just cause its new , don't mean its good .

 

That is true, I switched out alternators. We will see now.

 

I can appreciate that. One thing that helps is using either some slip on alligator type clips that go onto the probes of the volt meter that allow you to clip the probe in place.
https://www.amazon.com/Multimeter-A...s=multimeter+clip+leads&qid=1656080065&sr=8-6


A great alternative to those are short test leads with alligator clips on both ends, you can clip one end to the probe and the other end to the point to be measured. I use those all the time when working with high voltage (it's not a great idea to have high voltage/current run across one arm, across your chest/heart and down the other arm, for obvious reasons.

https://www.amazon.com/WGGE-WG-026-...s=electronic+test+leads&qid=1656080187&sr=8-3


Make the measurements when you can and post back here, I or somebody will explain what's happening and help you through this.

 

Thanks very much, lots of knowledge on the HAMB for sure.

 

If the alternator is charging, a screwdriver should stick to the back center bearing of the alternator. If it doesn't stick, the alternator is not charging. Got to be an iron or steel screwdriver.

 

Not magnetic, still only 12 volt charge at battery with 8 ga. wire direct from alternator to positive post. This is the second new alternator. Out of ideas on this end. I checked meter on our Ford van, at idle charge was 14volts plus. I ordered an alt from summit, local parts house has only rebuilt from china, we'll see. Thanks for all your ideas.

 

Grounded alternator, ran 8 ga wire to positive terminal on battery from alternator, still only get 12 volts charge at battery. Out of ideas here. I checked the meter on my Ford van, at idle charge was 14 volts plus. I ordered an alternator from summit, local parts place has only rebuilts from china. We'll see. Thanks for your help.

 

Check to see if all your connections are actually good. Start the car, rev the motor to 2K+ to ensure it has reached its trigger RPM to start charging. Then use your meter to check for voltage drop between the output terminal on the alternator and the positive battery post and also between the alternator case and the negative battery post. If you see more than a small fraction of a volt (.2 Volt or less) reading in either measurement, you have a poor connection somewhere. If the connections are good, the alternator isn't.

There are reasons why GM never used the one-wire units on cars/trucks, these were designed for use on industrial/farm equipment only.

 

Thanks, will do as soon as I get the Summit alternator.

 

I should have also noted that you should do these checks both loaded and unloaded. A connection that can show 'OK' unloaded can be much worse sometimes when a load is applied. Voltage drop is directly affected by current flow, applied voltage has nothing to do with it.

 

And have since been adopted far & wide by the multitudes used on most everything with very few problems .
Because GM did not use them may be due to multiple reasons , the first being cost benefit , a.k.a. the bottom line .

 

It wasn't about cost, these would be a cheaper install. No, it's about suitability for the application. The main flaw with these is the lack of the 'sense' circuit and their inability to adjust voltage output according to load and the corresponding voltage drop to the main harness. These alternators are a contributing factor in many cases of complaints about dim lights and other low-voltage ills.

I'm not saying they don't work, they just don't work as well as a three-wire. I would personally never use one except on a very bare-bones car, and even then I'd pay extra attention to wire sizes to prevent voltage drop.

 

If your instructions look like these you should be good to go. Summit sell some “inexpensive” products too.

 

Power Master one wire alternator from Summit-SUCCESS! Charging 14.5 volts at the battery. Third time (third alternator) is the charm. Thanks guys!!!!

 

I ran one wire setups for years, but have converted all mine to standard 3 wire 10SI Alternators in the last 10 years. The one wire alternators seem to be less reliable on when they will start to charge. Sometimes a little throttle blip would work, but not always. Never have had a problem with the standard 10SI setup. It isn’t really hard to wire.

 

One of the advantages of the standard 10/12SI 3-wire hookup is the sense terminal T2 - instead of just connecting the T2 sense terminal to the output lug of the alternator and losing its advantages as many people do, T2 can be connected with a small gauge sense wire to the + battery terminal or other point close to the battery (battery cable lug on the starter) to sense the system voltage at the battery, and to adjust the alternator output to keep that point at 14-1/2 volts, automatically making up for any voltage drops in the wiring between the alternator and the battery. Besides never having to rev a cold engine to get a 1-wire charging, proper use of the T2 sense terminal to insure the battery is getting full charge voltage is a real advantage of the 3-terminal system.

 

Happy motoring !

 

If you move the sense connection close to or right at the fuse panel, that will reduce voltage drop to the whole harness, not just between the alternator and the battery. This is what the factories do, and this will help with issues like dim headlights.