alternator problems

[Kevin Hawkins]

help
i have just changed the alternator on my 1990 tranny petrol from a 50 amp standard alternator to a 90 amp double pulley. All this is because I want to fit power steering. The 50 amp had a plug on the back with two red wires and one blue wire, but the 90 amp alternator only has a red and a blue wire. I have cut the plug off and twisted the two reds together and put it with the red to the alternator and put the blue one with the blue wire, but, alas, the charging light remains on. Can anyone help - have I connected it up right, or is it that I need a new alternator (the old alternator came from a scrap yard)? How do I test the alternator? This is driving me potty!!!
Any help would be very much appreciated.
Regards
Kevin Hawkins

[AndyG]

Don't understand what the alternator had to do with the power steering

It sounds like you've wired it up fine from what you've said

Was it an old alternator from the scrap yard you fitted

If you ran the engine with the cabling disconected you could've easily blown the regulator

Will probably have to come off for testing

[rover]

Sounds like its knackered, the blue wire is the one that puts the light out on the dash.


Rover.

[crazyscoot]

Test meter set to DC volts. put the leads across the battery terminals with the engine off, should have about 12 volts +-. Start the engine and do the same test, you should now have 14 volts+- if you dont then its the alternator knackered