TIP: Easy Alternator refurbish

If your mid-90's Ford has run up it's mileage to about 100 - 150 kmiles or so, you might want to undertake a quick Saturday project that will probably save you big bucks -and inconvenience- in the near future.
(MAny 20 year old and newer alternators are built similar to this)
Check out the back of the alternator to see if the voltage regulator (at the connector with the smaller wires) is held on by small torx screws.
If so, refurbishing which COULD be better than "rebuilding" - for a guy who is at all handy should be piece of cake.
Tools: - 3/8 or 1/2 inch breaker bar or whatever you use to release belt tensioner, - approp metric or sae tools for automotive access service. - 1/4 inch driver and small sockets plus small standard torx bits - standard size paperclip
Parts: - brush replacement set for your year, model and engine - new belt, optional - a dab of high temp bearing grease
Release tension and remove the belt, then listen carefully while you spin the pulley and check for free-spin and listen for bearing singing -you want to hear a little but no grinding or roiugh sounds- then wiggle the pulley back and forth, no sloppiness wanted.
If it fails these, put the belt back on.
Pull the connectors - they may be a little stiff- and unbolt the alternator.
With tape or marker, run a reassembly line from back housing to front housing
Remove the three housing bolts, tap the edges of the front (pulley-side) to loosen from stator (center section) and pull out by the pulley.
The stator and back housing are connected, dont attempt to separate.
Check commutator (brass rings) for galling and copper incursion into separator between them... if brush had gone and either is grooved continue on, the new brushes will just not last as long. Use fine sandpaper to smooth it if ring surface is rough.. DO NOT attempt to sand more than to get the high points off.
Check back bearing for some grease and for no "wash-board" on shaft bearing surface. This is a break-point: if the bearing/surface or commutator (and SOME brushes left) is in bad shape, you may want to just reassemble and plan to replace alt.
Remove the torx screws AT THE CORNERS of the regulator and remove it from back housing.
Remove the two torx screws that fasten the brush terminals to the regulator body. make sure not to lose the nuts.
blow or brush dust from brush holders/reg and insert the new springs and brushes, note that the wire slot aligns brush terminal with proper location, do rear brush first, sliding straightened clip in to hold it in, then front brush, sliding clip further in to hold both brushes in
fasten terminals with nuts and torx screws tighten just secure, not "hard".
using just enough grease to "skin" the bearing rollers, lube the shaft bearing surface... if you're anal and are going to blow dust out of the rear housing, plug the bearing cavity tightly with paper towel.
remove towel from bearing, reinstall regulator, then carefully slide alt back together following the marked alignment.
Make sure stator and each housing mate squarely.
Install the three housing bolts and tighten alternately until very secure. not ultra tight.
Check for free-spin
- - - - - - - - - - - - - -- - - - - -
Note this is a good alternative to buying a rebuilt as well... get a spare from a salvage yard and inspect it on the spot. If the alternator has not overheated or been zapped, there is every reaon to expect the regulator and diodes to last until the bearings go.
In fact, you dont know that the "rebuilt" hadnt been done exactly like this, just cleaned up more.
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Wrong => on 5.0's!
*replace old alternator* with a new series 3, the old has a undersized connector for the amperage and will burn up, smoke and flame at some point. Series 3 uses a terminal, not a connector. any alternator place will tell you this, they got paid bucks to replace them in fleets of 5.0 fords.
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Also with any alternator when you have it out, take it to an auto parts place and have them test it. It's cheap insurance and will tell you if the alternator has a bad diode or low output or whatever.
Ted
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I have to side with Backyard Mechanic. I'm fixing to roll the odometer for the third time, still using the original factory alternator. The brushes woreout at about 150,000 miles I replaced them and the alternator lasted about another 60 or 70 thousand miles before a diode shorted out. I pulled the OEM alternator and took it to an auto electric shop where I got it rebuilt for about fifty dollars, it is still in the engine today. (Special note, when the diodes fry disconnect the battery pronto!)

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They don't make things like they used to.
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Shawn wrote:

What kind of engine? Most engines have the alternator on them, not in them. I have seen some small engines (Kohler, B&S) that had the alternator built in, but not in autos.
Jeff
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having to jump start or use an external battery charger.
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wrote:

If this is a Briggs & Stratton Vanguard, they just came out with a 20/50 alternator option - a bigger alternator winding and permanent magnet set for the flywheel that will give you 20A output at ~1500 RPM and 50A output at full throttle ~3600 RPM.
More than enough juice for battery charging plus run a few headlights and taillights and a small stereo.
If this is an older lawnmower that can't be retrofitted, see if you have a place to get a v-belt pulley on the fan spinner or at the output shaft end. You can always bypass the flywheel lighting coil and hang a good old 60A Delco Motorcraft or Motorola car alternator on there. Who cares if it looks funny, as long as it works.
--<< Bruce >>--
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having to jump start or use an external battery charger.

A riding mower with a stereo. Now you are cooking with gas ! What's next ? A/C
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wrote:

having to jump start or use an external battery charger.

You were paying attention! ;-) "Four-Sixty" AC could be done if you have a small 12V fan on the top of the cowling aimed at the driver.
(CalTrans uses full-size tractors with articulated arm gang mowers to do weed abatement on the medians and shoulders, and they have fully enclosed cabs and AC. You almost have to, with the amount of dust and debris they stir up.)
Say you are building a directional boring machine with a Briggs engine. You need enough alternator to charge the battery and also run the safety deadman system, and the hydraulic actuator solenoids, and a few lights for night work, and...
Having 10A to 25A of 12VDC available makes lots of things easier.
--<< Bruce >>--
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I probably should have been more specific. The car is a 1988 Mustang GT with 289,000 miles on the odometer and the original, albeit rebuilt, alternator is still in the car's engine [compartment] to this day.

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Good sense. I would rather buy a "rebuilt" alternator & disassemble it to check for the problems you mentioned & if everything checks out ok, then I will just shelve it until the current alternator shoots the bricks & then swap them out. I may end up with a hefty core charge though.
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