As most of you know, some of the alternators we have gotten on our cars are shit. Usually the diodes crap out in the rectifier unit leaving you stuck with a several hundred dollar bill for either a rebuilt unit or a new unit.
Well I took it upon myself to take the thing apart and see what could be done to it. Surprisingly it is relatively easy to fix.
Tools Needed:
1. Disconnect negative battery cable.
2. Remove wiring from alternator
3. Releive tension on serpentine belt and take it off the alternator pulley.
4. Remove alternator from car.
Replace Rectifier:
Parts Needed (about $70 total):
1 Heavy duty rectifier unit. I recommend Part number 502-067 from National Quick Start Sales. This unit has a pure copper heat sink on it that is about as thick as a nickel coin!
http://store.alternatorparts.com/pa...ctifierforfordmotorcrafe6gtypealternator.aspx
1 Bearing Holder & 1 cap ( you can get these from Ford, or from an aftermarket source--I had to buy 25 each of them since they're so damn cheap. I got them from Amsco Valley Forge, part numbers: FD-311 and FD-454 respectively.
Repair/Replacement Procedure:
1. Begin by removing the back case. Remove the three (3) 5/16" screws that holds the altnerator together. Don't worry, it will not fly apart. Take the flat head screw driver and use it to pry the back case while pursuading it with the 3/8" drive extension and hammer--use the extension as a punch and tap the ears on the back case while rotating from ear to ear to remove the back case. It should come off easy:
Once the back case is off, desolder the 6 pairs of wires from the stator that are attached to the old rectifier unit.
With the t-20 torx screwdriver, remove the voltage regulator-brush holder from the back. Don't worry, the brushes will not pop out on you!
Remove the 3 screws and then the voltage regulator/brush holder and set them aside for future use.
Now remove the old rectifier unit. You can shitcan this once it is removed
Now the back of the alternator should look like this:
What you now see is the stator (outside coils) and rotor. A DC current is passed through the coils in the rotor via the brushes. This caused a magnetic field to form (Ampere's Law). Since this magnetic field is moving (rotating) and electric field is setup in the outside coils (stator) Faraday's Law. This alternating current is then passed through a bridge rectifer to turn it into pulsed DC current, which charges your battery and runs the car!
Ok, physics lesson over...lets get back to the rebuild!
Now is a good time to see if your stator is ok. You should find by using the ohmmeter there are 3 independent paths for current to flow. If you find more than that, your stator is shorted.
Put the new rectifier on the alternator, aligning it to the 6 pairs of stator wires. There will be 2 wires together and then 4 wires together; there are also U shaped cutouts on the rectifier for the stator wires to pass. Align the new rectifer unit so that it takes the 2-4 position like this:
Clock the new rectifier unit's "ears" to align with the 3 screw openings.
Center the stator wires in the U Shaped gaps like this so they don't touch the housing of the rectifier or unit:
I used the punch to gently bend and move the wires so they are centered. Be careful not to rub off the varnish on the wires because that's their only insulation!
Now crimp the 6 pairs of stator wires to the new rectifier unit:
Fun time now..with a heavy duty soldering gun (you need heat here!), solder the six pairs of wires to teh new rectifier unit. When you're done, be sure they look similar this:
Be sure to get the wire and crimp HOT and let the solder flow to that! Tin your iron good so you get good heat flow. You don't want a cold solder joint here! I wrote a tutorial on soldering on the board...use the search to look it up.
Position the voltage regulator/brush holder like this:
Use your finger to depress the two brushes like this:
Put the unit on top of the bearing and start it down the shaft while keeping each brush pushed in until you can let go.
Position the voltage regulator/brush holder over the 3 screw holes.
Re-install the three T-20 torx screws:
Put the back case of the alternator back on in its proper alignment. The bearing will be sloppy in the center hole since we need to install a bearing holder:
These two plastic parts usually get broken, so it is a good idea to have some replacements around....the cap is on the left and the bearing holder is on the right.
There are 3 raised notches on the outside of the bearing holder that will mate with the 3 notches carved in the back center hole. Align them and then start the bearing holder down into the center hole as shown below.
Once you get it started, use a rubber mallet to tap it into place:
continued on next post.
Well I took it upon myself to take the thing apart and see what could be done to it. Surprisingly it is relatively easy to fix.
Tools Needed:
- 1/2" long handled pull handle to relieve belt tension.
- Tools to remove alternator from car (I have a Saleen SC, so I use a 12mm, 3/8" drive socket--your application may be different.
- Heavy Duty Soldering Iron
- 60% Tin (Sn) 40% Lead (Pb) rosin core solder--fuck that lead free RHoS shit--I use real solder.
- Wet sponge to clean soldering iron
- Solder sucker
- Ohmmeter
- Regular Hammer
- Rubber Mallet
- Flat Head Screwdriver--Medium sized
- Punch (or similar round smooth & long type tool)
- 3/8" socket extension about 5-7" long.
- #20 Torx screwdriver
- 5/16" socket and nut-driver or ratchet.
1. Disconnect negative battery cable.
2. Remove wiring from alternator
3. Releive tension on serpentine belt and take it off the alternator pulley.
4. Remove alternator from car.
Replace Rectifier:
Parts Needed (about $70 total):
1 Heavy duty rectifier unit. I recommend Part number 502-067 from National Quick Start Sales. This unit has a pure copper heat sink on it that is about as thick as a nickel coin!
http://store.alternatorparts.com/pa...ctifierforfordmotorcrafe6gtypealternator.aspx
1 Bearing Holder & 1 cap ( you can get these from Ford, or from an aftermarket source--I had to buy 25 each of them since they're so damn cheap. I got them from Amsco Valley Forge, part numbers: FD-311 and FD-454 respectively.
Repair/Replacement Procedure:
1. Begin by removing the back case. Remove the three (3) 5/16" screws that holds the altnerator together. Don't worry, it will not fly apart. Take the flat head screw driver and use it to pry the back case while pursuading it with the 3/8" drive extension and hammer--use the extension as a punch and tap the ears on the back case while rotating from ear to ear to remove the back case. It should come off easy:
Once the back case is off, desolder the 6 pairs of wires from the stator that are attached to the old rectifier unit.
With the t-20 torx screwdriver, remove the voltage regulator-brush holder from the back. Don't worry, the brushes will not pop out on you!
Remove the 3 screws and then the voltage regulator/brush holder and set them aside for future use.
Now remove the old rectifier unit. You can shitcan this once it is removed
Now the back of the alternator should look like this:
What you now see is the stator (outside coils) and rotor. A DC current is passed through the coils in the rotor via the brushes. This caused a magnetic field to form (Ampere's Law). Since this magnetic field is moving (rotating) and electric field is setup in the outside coils (stator) Faraday's Law. This alternating current is then passed through a bridge rectifer to turn it into pulsed DC current, which charges your battery and runs the car!
Ok, physics lesson over...lets get back to the rebuild!
Now is a good time to see if your stator is ok. You should find by using the ohmmeter there are 3 independent paths for current to flow. If you find more than that, your stator is shorted.
Put the new rectifier on the alternator, aligning it to the 6 pairs of stator wires. There will be 2 wires together and then 4 wires together; there are also U shaped cutouts on the rectifier for the stator wires to pass. Align the new rectifer unit so that it takes the 2-4 position like this:
Clock the new rectifier unit's "ears" to align with the 3 screw openings.
Center the stator wires in the U Shaped gaps like this so they don't touch the housing of the rectifier or unit:
I used the punch to gently bend and move the wires so they are centered. Be careful not to rub off the varnish on the wires because that's their only insulation!
Now crimp the 6 pairs of stator wires to the new rectifier unit:
Fun time now..with a heavy duty soldering gun (you need heat here!), solder the six pairs of wires to teh new rectifier unit. When you're done, be sure they look similar this:
Be sure to get the wire and crimp HOT and let the solder flow to that! Tin your iron good so you get good heat flow. You don't want a cold solder joint here! I wrote a tutorial on soldering on the board...use the search to look it up.
Position the voltage regulator/brush holder like this:
Use your finger to depress the two brushes like this:
Put the unit on top of the bearing and start it down the shaft while keeping each brush pushed in until you can let go.
Position the voltage regulator/brush holder over the 3 screw holes.
Re-install the three T-20 torx screws:
Put the back case of the alternator back on in its proper alignment. The bearing will be sloppy in the center hole since we need to install a bearing holder:
These two plastic parts usually get broken, so it is a good idea to have some replacements around....the cap is on the left and the bearing holder is on the right.
There are 3 raised notches on the outside of the bearing holder that will mate with the 3 notches carved in the back center hole. Align them and then start the bearing holder down into the center hole as shown below.
Once you get it started, use a rubber mallet to tap it into place:
continued on next post.
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