Hot alternator... car just sitting there? Ford, Taurus, 2000, 3.0?

Question

Hey, poped hood open and started to work on car... touched alternator and that puppy was hot! What the?

Disconnected battery and did my repair on something else and hooked back up.

So why is my alternator hot?

Answer 1

if the car has not been run and everything else is stone cold : suspect a failing diode[there six of them 3pos. 3neg.] these are the " one way valves" that convert a.c. to d.c. when failing the alt will stay warm and kill the battery but will still charge w/ engine running. typicly they will squeal when failing under a load . ac will show up in the dc when checked on a sun v.a.t. 40 when turned to diode check and load knob turned . don't guess go to a reliable shop and test. if bad this is a pretty easy D.I.Y. job dont forget to disconnect battery ground before removing alt.

Answer 2

How long was it sitting there before you touched it?



I find the alternators keep heat in them for a while (for a few hours usually) more than say 1 hour of sitting.



If it was hot to touch over say 3-4 hours or more of sitting, then I would look at a defective internal problems with alternator.

Answer 3

sound,s like it might be trying to over charge,,this a condition caused by a weak battery or something on in the car that is drawing a lot of power,,and in some rare occasions the alternator will start to run hot simply because the bearing,s in the end,s of it are getting worn out,,you may even notice a slight sq eek out of it once in a while,,just keep a watch on it,,because in some occasion,s,i have seen them do what is called a melt down,,they simply over heat,so much that they fry there own inside,s,,hope this help,s.

Answer 4

The voltage regulator which is internal to the alternator uses a grounding system to regulate output voltage. In other words as the voltage goes high it uses contacts that send it to ground. If these contacts stick it sends battery voltage to ground all the time, hence HOT feel to alternator. Its suprising you haven't killed a battery or not been able to start because of low battery. REPLACE the alternator.

Answer 5

check the wiring that is a sign of it is grounding out on something cause when 12volts is crossed it gets very hot

Answer 6

Sounds like it might be wired wrong. It should be hot from sitting.

Answer 7

alternator is still in on position,meaning it's still being powered by battery.