2001 Sport 3.5 Battery/Brake Light Warning
 

Hello folks,

I have a 2001 Montero Sport 4WD 3.5L XS. For the past month I've been smelling burning oil from a leak somewhere. This morning at a stop light the Battery and Brake lights started to flicker and I could tell she was close to stalling. I feathered the gas and managed to get to work. No issues until I got close to home and the same thing happened. Thanks to the forum here I was able to determine that this warning light combination is indicative of a failing alternator... likely due to oil getting in or on it from the leak I described. I'm curious if the alternator could be salvaged? Could it be cleaned
externally/internally without being removed with a safe cleaner or is this wishful thinking?

Thanks in advance for any help with this.

Well done for actually doing some homework before asking a n00b question.

Alternators are four bits: rotor, stator, rectifier, regulator.
if the output is "just low" you may well be able to replace the rectifier and drive on.
on newer vehicles with computers and bullsh*t, you may well have fried something else.

if the damage is cooked stator winding, then you're basically looking at a new alt.

anything can be stripped, cleaned and reassembled, if you're so inclined.

get a multimeter on the output and see what's what.

as for the oil leak, it should be pretty obvious. if it's above the alt, i suspect the rocker cover, which should never be allowed to leak because you should be doing preventative maintenance on your vehicle, all the time.

post back what you find out.

On the Monteros, the oil on the alternator usually = leaking cam seal. I had this happen to me and when i called mechanic inquiring about where the oil could possibly be coming from, as soon as I said that oil is on the alternator, he said - bad cam seal (he was right too).
Technically the alternator is fully rebuildable and there is a procedure in the FSM for it. The problem with this is that we, unfortunately, live in the society where repairing things is no longer a typical course of actions. You are almost expected to just swap a $500 unit instead of replacing a $50 component. I do not even know if you may be able to find individual components needed for the rebuild. If you have good connections you may be lucky enough to get them and can go that way. Pull the FSM and read the procedure. That will give you an idea if you have the skills and patience to do a rebuild.

Make sure you fix the oil leak before you re-install the repaired or new alternator.

I've rebuilt a dozen alternators for my own wagons, mitsis seem to eat them. mainly just swapping out rectifiers, brushes etc.
...well worth not shelling out for a new one.

I agree that rebuild is well worth the savings. The issue is, that here (US) the marketing departments think we are incapable of doing so and we should do a simple thing and lighten our wallets by swapping big hunks of hardware. I wonder if rebuild kits are more readily available in the rest of the world.

probably. so often yanks come out with "i've replaced this, and this, and this, ann this, and this, and this, aaaaaand this, and it still doesn't go"
I thought you must have really really cheap parts.

Haha, I wish