Alternator
- Thread starter fg4oz
- Start date
pugslyyy
Expedition Vehicle Engineer Guy
Hmm, shouldn't need an alternator to start. What are the symptoms? No crank/slow crank/crank but no start/etc?
SkiFreak
Crazy Person
I have two words for you.... clamp meter.
In my opinion it's probably the easiest way to confirm that you are getting charging current to your batteries.
And, as pugslyyy has said, the alternator plays no part whatsoever in starting the truck, but it does keep your batteries charged.
unkamonkey
Explorer
The most overused and best answer is to check your ground wires.
gait
Explorer
yup, clamp meter, for amps, and measure the battery volts with volt meter. The difference in volts between engine and charging is very noticeable.
plus, somewhere near where engine meets gearbox there's a heavy strap from engine to chassis. Its the main earth return for the starter. Its been known to vibrate away to nothing and significantly reduce the effectiveness of the starter motor.
I replaced it when I realised it was broken. The starter still worked, just that the amps probably flowed through smaller wires and didn't like it. Possibly also the alternator return.
plus, somewhere near where engine meets gearbox there's a heavy strap from engine to chassis. Its the main earth return for the starter. Its been known to vibrate away to nothing and significantly reduce the effectiveness of the starter motor.
I replaced it when I realised it was broken. The starter still worked, just that the amps probably flowed through smaller wires and didn't like it. Possibly also the alternator return.
As an aside, my FG has no OE voltmeter gauge. I bought a triple 12 volt outlet/USB expander which I have plugged into the OE cigarette outlet. It displays volts. Not only does it show how the alternator is working but it also tells me when the glowplugs stop their cycle as my truck only displays the glowplug light on the dash in cold weather.
https://www.amazon.com/gp/product/B06VTQDDQW/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B06VTQDDQW/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
unkamonkey
Explorer
To tell the truth both of my Jeeps have amp meters. And to me they tell more about how the system is working than a volt meter would ever tell me.
Some say that they are not safe but in my many years of off roading I have never cooked a Jeep.
Some say that they are not safe but in my many years of off roading I have never cooked a Jeep.