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Questions regarding an Alternator installation

  • Thread starter Thread starter yeska68
  • Start date Start date Feb 8, 2004
Y

yeska68

New Member
May 2, 2002
45
0
0
Oakland ca
Feb 8, 2004
#1
  • Feb 8, 2004
  • #1
I have a 1968 coupe 2v 289 all stock. My alternator went bad so i removed the old and installed the new one. After installing the new one two things changed:
1. There is a loud screeching sound when i start it up but after it is warm or if i give a little gas and the high idle goes down the noise gets low until I step on the gas the noise is ridiculously loud up until 30 mph then the noise goes away after 35 mph . I have no clue what this could be.

2. The arm in the instument panel for the alternator is 3/4 to the left (when going left to right) My old alternator used to stay a cinimeter to the right of the middle and never really moved. Now the arm sometimes moves all the way to right or 3/4 to the right.

What could this be???

other then this the car pretty much performs good (rather how it used to be)
 

jikelly

20+ Year Stangneter
Jul 9, 2003
872
53
99
Lubbock Tx
Feb 8, 2004
#2
  • Feb 8, 2004
  • #2
I would assume that the screeching is the belt. Is it tight? The only other thing I could think might be causing you a problem is a problem with the wiring.
 
Y

yeska68

New Member
May 2, 2002
45
0
0
Oakland ca
Feb 8, 2004
#3
  • Feb 8, 2004
  • #3
RE alternator

i marked the exactly where the old alternator was and it was not screcching before. but i will loosen it. Can u buy am alternator that is over charging if so what would be the result of this

What about the instrument panel arm that keeps moving is it normal to move around or should it stay in one place??
 

jikelly

20+ Year Stangneter
Jul 9, 2003
872
53
99
Lubbock Tx
Feb 8, 2004
#4
  • Feb 8, 2004
  • #4
It should stay in one place or at least stay to the right while the engine is running above 1000 rpm. If the alternator was over charging I'm not sure what would happen. Of all the alternators I've had I never had that problem. I have however had a problem simular to yours, but my alternator was bad. I was hoping your problem would be something simple. Look over your connections and make sure your belt is tight. You may have to get another alternator from the store.
 

68GEETEE

5 Year Member
Nov 21, 2003
481
5
38
Texas, USA
Feb 8, 2004
#5
  • Feb 8, 2004
  • #5
I think your problem sounds like a loose belt. If the pulley isnt turning fast enough, that would cause your gauge to read inaccurate. Start by tightening and / or replacing the belt. . Did you check the pulley to make sure it was the same size as the one you had on the old alternator? The belt may be too big / too small for the new pulley.
 
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