wacky windshield wipers !!

[Mike Miller]

My car is a 74 Charger, i have the same 2speed wipers as millions of other mopars. i only drive it for fun so for the last 5 years that i've owned it it has never been in the rain, however i ran the wipers and know they work. A few weeks back as i was driving they took one swipe by themselves.I turned on the switch, they worked so i did not think much of it. 20 minutes later i get an acrid smell in the car so i head home. I get in my driveway and my system is charging full blast and yes, battery acid all over the place. i throw in a new alternator and battery and regulator, start it and same thing. i can hear a soft whining sound under the hood..its the wiper motor. i unplug the motor and my charging system goes back to normal. likely a 50 year old motor i put in a new one ,cycle it a few times.. looks good. then it pins the wiper blades down to the cowl and i get the whine again.. the motor is stuck and binding.. unplug and it stops. I have been strictly a Mopar guy since the early 70s and had my hands on many but i cannot make sense out of this.. i looked at the mind boggling list of electrical tests for all of this and its overwhelming to me.. has anyone ever had this issue before besides me ?? I know its not the linkage but will check that again just to rule it out.. any ideas ??

 

[T2R9]

Remove the arms, run the motor and let it park. Then put the arms back on in the parked position. Could very well be the motor is trying to park the arms and they are binding it up. I have run into this a few times and always run the motor thru it's paces before putting the arms on.

 

[pnora]

There should of been no charging system problem. If there was an excess load the circuit breaker in the switch should of been cycling.

 

[Mike Miller]

Could you please explain more about a circuit breaker in the switch ?? I have many detailed repair manuals for this car and cant even find a reference as to what fuse the wiper system runs off of.. i suspect the switch may be a problem but will take T2R9s advice and try to cycle with the arms off.. thing is the old unit started doing this as well so it confuses things a bit.. that setup was working for years until it went off by itself the time i was driving it and it freaked out. makes no sense at all.. and thank you for the replies.