hey all,

well i put a new alternator on my 90 w250, because it stopped chargeing, well now the new one isn't charging. So i got it checked and it was pushing 15 volts so it was fine, but then i thought the external regulator. I replaced that and still no charge. Any help is appreciated.

thanks
garrett

 

Be sure the firewall were the regulator attaches is clean.because the regulator housing needs to be grounded.And I have had bad "new" regulators before

 

ok will do

 

i've had bad new regulators too. i have all new parts under the hood of my ford except i have a 1982 regulator because the new one was junk out of the box.

 

o wow that sucks i hate when that happens

 

Check the fusible link. If you are pushing 15 V at the alternator to me that means the alternator is not seeing the battery. Check your wiring from the alternator all the way to the battery, right behind the battery should be fusible like. You can also read voltage for the field across the two small terminals on the back of the alternator, this will tell you if the voltage regulator is working or not. The higher the voltage here the more their regulator wants from the alternator.

 

ok i will do that thanks sir

 

Does a '90 have a crank position sensor? I had some wires break on mine do to a bad fan belt and it caused mine to quit charging.

 

well i fixed it, turn out the battery has to have 12.2 volts before it can turn the exciter on the regulator on to charge the battery it was a pain to figure out.