Alternator Replacement
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Intermediate
Joined: Jan 2019
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From: Seabrook, NH
Alternator Replacement
Hi All - 74 350. After a bonehead move, some troubleshooting later, I am in the process of replacing my alternator. I removed the old alternator. During the removal, I simply loosened the 1/2" nut above, rotated the alternator inward and then removed the belt from pulley. I then dropped it toward the inner fender (driver) and removed the 9/16" bolt.
However to replace it, I have the 9/16 bolt in finger tight, but cannot get the 1/2" bolt in since I cannot pull the belt to be in tension. There is no tensioner on the car, am I doing something wrong? I doubt the right thing to do is to use a pry or equivalent and "set the alternator" as such and then thread the 1/2 inch bolt in?
However to replace it, I have the 9/16 bolt in finger tight, but cannot get the 1/2" bolt in since I cannot pull the belt to be in tension. There is no tensioner on the car, am I doing something wrong? I doubt the right thing to do is to use a pry or equivalent and "set the alternator" as such and then thread the 1/2 inch bolt in?
Last edited by SeventyFourStinger; Aug 29, 2020 at 05:08 PM.
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Well, if the belt fit before, it still should.
check to see that the belt is inthe correct groves in the other pullys. Check that the pully on the new alternator is the same size as the original.
check to see that the belt is inthe correct groves in the other pullys. Check that the pully on the new alternator is the same size as the original.
Last edited by 4-vettes; Aug 29, 2020 at 06:09 PM.
Thread Starter
Intermediate
Joined: Jan 2019
Posts: 29
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From: Seabrook, NH
Thanks - yes, the belt is seated in all grooves and fits appropriately in new alternator.
To clarify my question, during the alternator removal I didn't use a tensioner, or take off any other accessory, I loosened the upper bolt, and then got the belt off. During the install of the new alternator, how do I get the tension off the belt to get the alternator seated and subsequently put the tension back on the belt? Was i supposed to remove other accessory, etc?
To clarify my question, during the alternator removal I didn't use a tensioner, or take off any other accessory, I loosened the upper bolt, and then got the belt off. During the install of the new alternator, how do I get the tension off the belt to get the alternator seated and subsequently put the tension back on the belt? Was i supposed to remove other accessory, etc?
Burning Brakes
Joined: Feb 2020
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From: Central NJ
If it's like mine you Loosen up the top bracket, then you can start the top bolt. Get both bolts a little past finger tight and take a stick and gently pry the alternator back to put the proper tension on the belt, don't use the valve cover to pry off of. Tighten the top bolt, the top bracket and the lower bolt. I'm assuming your 350 has a similar arrangement as my crate 350. As stated above make sure the new pully is the same as the old one.
60
60
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Yes it really is this simple. Install lower long bolt, do not fully tighten. Install upper 5/16th's bolt you referred to as a half inch bolt. Run it up finger tight, back it off about a turn. Swing alternator towards valve cover as far as it will go. Walk belt onto alternator pully. If it's tight sometimes rotating the pully as you go helps. Once belt is on all 3 pullys and in the Correct groves, swing alternator back toward the fender. With a stick, hammer handle or what ever fits in there pry alternator back,(Stick on block, not valve cover). Get your belt tention correct and tighten top bolt to hold. Remove stick. Tighten lower bolt and nut.
double check belt tention. Done
double check belt tention. Done
