I bought a new truck to me, and am having some problems that i guess the previous owner has been working on.

75 f100 360

If it sits for a day the battery is dead. Has had a new battery, and voltage regulator put on it. When i touch the positive cable to the battery the regulator clicks one time real loud is this normal?

I guess it could be a bad regulator again i didn't put these new parts on it.

My next thing is to unhook radio etc and see if these are the problem also. Just curious about the clicking regulator.

Thanks!

 

You disconnect the NEGATIVE battery cable, install a test light or VOM and start pulling fuses until the light goes out.

If you pull all fuses and the light remains, have the alternator tested for a bad diode.

Josh

 

the voltage reg shouldn't make a sound id cut that harness apart and check it or disconect it and let it sit a day. ill bet the bat is good after sitting.

there's a few options my
#1 is a 3g swap
#2 a 1 wire gm alternator
#3 rewiring the puny stocker

 

The battery isn't going to magically fix itself if it has been drained. The correct way to approach this problem is to understand where the exact issue lies and focus on that, not randomly cut into the harness or throw upgrade parts at it with no direction.

To the OP: The one-time click from the regulator sounds like the field relay in the regulator closing. This would make sense if it's an electromechanical regulator, but I'm surprised that's the case if it's a new regulator. Are you sure the click is coming from the regulator and not the starter solenoid? If the regulator were to click, it shouldn't be very loud at all.

Assuming the noise is coming from the regulator, however, this should not be happening with the truck OFF. If your truck has an amp gauge, this could happen if the key was left ON or there's a short in the upstream wiring to the key, either of which would apply power to the S terminal of the regulator and energize the field relay. If your truck has an ALT light, the field relay isn't supposed to close unless the engine is actually turning (and the alternator stator terminal has power).

Try this test: disconnect the regulator, and connect the battery (always connect the NEGATIVE last). Measure the voltage at the S terminal of the plug that connects to the regulator with the key off. The voltage should be ZERO. If it is, yet the relay clicks, replace the regulator.

If your regulator is closing the field relay while the alternator is not charging the battery, it will drain the battery. Josh's fuse test is also a useful tool for determining if the short comes from any accessory loads. It won't tell you if the short is coming from the regulator, but unplugging the regulator while performing the test will do the same thing.

 

Thanks fmc400,

I was looking at it in the dark, and wasn't sure if it was the regulator or solenoid. They are right by each other and it was hard to tell. I will do the test you say and see what i get. If it is the solenoid making the noise then what?

Bullitt390

thanks for the help i will use that for sure.

 

If you're not sure which one was clicking, then I would recommend figuring that out first before proceeding any further.