Forum Discussion
MEXICOWANDERER
Feb 01, 2016Explorer
The 3G, 4G, and 6G Ford alternators are rectified WYE alternators and have decent low speed performance. But they are NOT hairpin alternators. The G alternators (G stands for Generation) with 130-amp stators have PURPLE insulation coating on the stator windings. The lesser amperage G models have GREEN stator windings.
Yes there are hairpin alternators that have correct bolt mounting for many Ford engines. Two cautions: Adapting the voltage regulator plug and adapting the pulley. Both are unique and both must be compatible with your G mounting configuration.
Take LOTS of images with your camera using as many shooting angles as you can of your existing alternator. Especially of the regulator and inside the pulley and belt interface. Take them to your Ford dealer then begin the search. As far as I know Ford does not sell the voltage regulator pigtail for the hairpin which by the way is a Nippondenso creation, not a Motorcraft.
The hairpin curve is a hot temperature curve and from experience I can tell you the hairpin outperforms the rectified wye alternator at low speeds far and away more than "double". Try triple to quadruple. Any comparison is a real eye-roller. At 120 rotor RPM a 270-amp hairpin will be capable of producing a not insignificant amount of power. The performance chart that was mentioned does not do the issue justice.
My Lambordini cannot crank the Delco if the regulator is switched on with the engine's starter motor trying to turn the engine over. Absolutely locked rotor condition. This is with a 2.14 horsepower Magnetti Marelli starter. A 13-ampere rotor draw is significant (24-volts). That should give some idea of the field strength needed to saturate the windings and laminations.
Time to get out the flashlight and mirror and go look at your stator winding color :)
Yes there are hairpin alternators that have correct bolt mounting for many Ford engines. Two cautions: Adapting the voltage regulator plug and adapting the pulley. Both are unique and both must be compatible with your G mounting configuration.
Take LOTS of images with your camera using as many shooting angles as you can of your existing alternator. Especially of the regulator and inside the pulley and belt interface. Take them to your Ford dealer then begin the search. As far as I know Ford does not sell the voltage regulator pigtail for the hairpin which by the way is a Nippondenso creation, not a Motorcraft.
The hairpin curve is a hot temperature curve and from experience I can tell you the hairpin outperforms the rectified wye alternator at low speeds far and away more than "double". Try triple to quadruple. Any comparison is a real eye-roller. At 120 rotor RPM a 270-amp hairpin will be capable of producing a not insignificant amount of power. The performance chart that was mentioned does not do the issue justice.
My Lambordini cannot crank the Delco if the regulator is switched on with the engine's starter motor trying to turn the engine over. Absolutely locked rotor condition. This is with a 2.14 horsepower Magnetti Marelli starter. A 13-ampere rotor draw is significant (24-volts). That should give some idea of the field strength needed to saturate the windings and laminations.
Time to get out the flashlight and mirror and go look at your stator winding color :)
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