Single phasing is when you have two hots or more going to an electrical source. My battery keeps dieing and I think I know why. I hook up the battery box, key is off and soon as I turn the battery box on I hear a low humming, grinding sound. I unplug the here fan. I am thinking it's coming from the starter. When I try to start the jeep it sounds like a starter kicking in but with a low battery. My thought is the starter solenoid or solenoid is bad sending a little bit of juice to it so the gear is spinning but not engaging because it's not getting the full voltage. What do you guys think?

Jeep is an 88 Xj Waggy...

 

The 1st thing you need is Hooked on Phonic's because I didn't understand 1/2 of what you were trying to explain.

Now, you say the starter sounds like it's trying to start with a low battery, but the battery keeps dying. Did you check the voltage in the battery and if it has 12 volts did you test it for an amp draw? It would make sense that it's sending a "little bit" of juice if the battery is low.
My question is, what is a here fan? And when you say battery box, do you mean the battery itself or are you hooking up something somewhere else say at the power distribution box?

 

Hmm, ok let me try this one.


The battery is dead. Something is draining it but that is another issue.

I have a jumper box that I hooked up to the battery. When I turn the box on to jump the waggy I hear a low humming grinding sound. When I turn the key the starter acts normally but doesn't turn over as fast because of the dead battery. I would need to let the box charge the battery up a bit more for the starter to turn over faster. However, I don't want to damage the fly wheel by letting the starter run like that. I sounds as the starter gear that turns the fly wheel isn't coming out to contact the fly wheel but sitting there running. Seems like it's getting half it's voltage, but when I turn the key it's getting all of it's voltage and I hear the starter turning over the engine.

 

So have you checked the starter solenoid or starter yet. Also the ignition switch and relays. Sounds like something is stuck or jammed causing the starter to turn all the time.

 

Well you're 1st issue is to find out if the battery is any good any more. You'll get nowhere if you had a dead cell even with the jump box on it. Where do you hear the humming sound from? The starter area? You might be hearing the fuel pump turning on since it needs to prime the lines before actually starting it. If you hear a growling then it may be the solenoid on the starter that is stuck in. That can also cause a drain on the battery. What I don't get is how you have low voltage sitting but get full voltage when turning the key. Have the battery checked and/or charged if it's not shot. Check your battery terminals and ends. Make sure the connections are all good. Tap on the starter solenoid and then when proper 12+Volts are present attempt to start it and see what it does.

 

Well I hear the growling, humming or grinding sound coming from the passenger side of the engine down towards the starter. I first thought it was the heater fan as it was right there. I unplugged it and that wasn't it. Hmm, never thought it could be the fuel pump. However, that is back @ the tank right???

 

Yes, on the newer years is it an "in tank" assembly and I'm almost positive that you would have the same set up. Either way it's in the rear of the vehicle. Sometimes the sound travels and you can easily mistake where the sound is coming from. If it's coming right from the starter, it sounds like it's shorted. If you have taken care of the battery issues and still have the problem, you're going to have to remove the starter and bench test it to see what it's doing. There aren't too many things that will "humm" when the key is on but the vehicle is off. Keep us posted. Goodluck.

 

the abs pump will hum if the bracket is removed or broken