Converted from generator to Alternator and won't crank unless I have a charger on the battery

[Guest CNCFabs]

So I am helping a friend with his 1955 Buick Century.  I've tried to find a topic on this and was unsuccessful, so I apologize if this has already been covered.

So I did air ride suspension on his car and the compressors pretty much fried the generator.   I retro fitted a 90 amp 1 wire Alternator.  I ran a new wire straight to the battery.  The wire that needed ground from the generator to let the vehicle know that engine is off so I could start it with the gas pedal, has been temporarily grounded, just to start it for now. I know I will have to work on that so it wont crank whiles driving.  well, once the car didn't even crank, I put a charger on the battery and it cranked.  I got a new battery because when i checked the battery it said it was no good.... With the new battery, it is doing the same...  The battery shows 12.5 volts... but even if the amperage was low, wouldn't it at least try and crank?  Any info would be greatly appreciated.

 

Thanks

[61polara]

You may have shorted your battery as well.  You need to load test it, because if it cranks with the battery charger on, you have it wired ok.

[JohnD1956]

Did you polarize the Voltage regulator when you had the generator and reconnected the battery after installing the compressors?

 

If not I'd start looking for a wire with burnt insulation that is touching a ground.

[KongaMan]

I might start by trying to figure out why the generator fried in the first place.

 

FYI:

 

[Beemon]

Did you ground the alternator?