100 Amp Alternator problem
Thread Starter
Instructor
Joined: Jun 2005
Posts: 156
Likes: 0
From: Liverpool NY
100 Amp Alternator problem
I just bought a 100 amp alternator for and 82. I have an electric fan and electric water pump so I figure the extra amps can't hurt.
The new alternator has the same 2 prong plug on the side and the battery post/bolt on the back, but there is no other place to hook the other wires up (smaller than the battery wire).
The alt. that just burned up and 2 post/bolts to put wires on the back of it and the new one only has one.
Anyone have any thoughts on this?
The new alternator has the same 2 prong plug on the side and the battery post/bolt on the back, but there is no other place to hook the other wires up (smaller than the battery wire).
The alt. that just burned up and 2 post/bolts to put wires on the back of it and the new one only has one.
Anyone have any thoughts on this?
Burning Brakes
Joined: Aug 2007
Posts: 1,173
Likes: 1
From: Liberty Missouri
I just reread your post I am not familiar with the 82 but if its wired like I think you should only be missing the ground post. I would guess it just getting its ground from the engine block. I would hate to tell you something that’s not correct so I will let someone with more knowledge of the 82 take this one.
Burning Brakes
Joined: Aug 2007
Posts: 1,173
Likes: 1
From: Liberty Missouri
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Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
According to the 82 wiring diagrahm, you have the 2 wire plug with a red wire and brown wire, the large red bat wire and the only other connection it shows is a ground. Alternators are usually grounded to the case and the extra ground is just for good measure. If the ground wire is the one in question, there is a bolt hole on the back of the alternator for grounding.
Last edited by '75; Apr 24, 2008 at 10:43 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If you are running additional load from the alternator (water pump / fans), you need to make sure any original wiring which carries that extra load is 'beefed-up" to handle it. You've probably doubled the current on any existing lines in those circuits. You can replace affected wiring with larger wire or just run an additional parallel line with it.
Thread Starter
Instructor
Joined: Jun 2005
Posts: 156
Likes: 0
From: Liverpool NY
Run an additional line to the battery or to the fan and pump also?
Do I need to do that with just these 2 components drawing power? I thought the alternator puts out on demand (like some women I know) and if I'm not demanding the full load (which I won't be) then I didnt have to worry about heavier wire.
Do I need to do that with just these 2 components drawing power? I thought the alternator puts out on demand (like some women I know) and if I'm not demanding the full load (which I won't be) then I didnt have to worry about heavier wire.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The only wires you need to be concerned with are those wires taking additional load. The feed wire coming out of the alternator needs to be sized for 100 amp capacity; and existing wiring which transfers that load to the fans and water pump need to be resized. The main battery wiring probably does not have to be increased unless you really have a badly drained battery. Remember, your new alternator will provide 100 amps to the battery if the battery calls for it.
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
The only wires you need to be concerned with are those wires taking additional load. The feed wire coming out of the alternator needs to be sized for 100 amp capacity; and existing wiring which transfers that load to the fans and water pump need to be resized. The main battery wiring probably does not have to be increased unless you really have a badly drained battery. Remember, your new alternator will provide 100 amps to the battery if the battery calls for it.
But I don't know if they quit using that horrid copper-plated aluminum battery cabling by 82 or not. If the wires are original and are aluminum, I'd replace them with the new Delco replacements which are 100% copper. The aluminum cables have been known to corrode internally and cause fun intermittent starting problems.
Racer
Joined: May 2007
Posts: 285
Likes: 0
From: Ga.
On my 82, there isthe 2 prong plug, a bat terminal for red wire, and there is a 3/8" bolt ground near the valve cover. There should be the ground wire from the rear, and another green wire that will ground with the black.
Hope this helps!
Hope this helps!
Le Mans Master
Joined: Nov 2004
Posts: 7,186
Likes: 45
From: detroit area
upgrade your main wires....
i cooked my original ground wire when i had my audio and not a big enough alternator....
long story short and 700bucks later (due to a surge and a few cooked items)....... i have a 1 odd guage ground wire and i ran a 10 guage wire from the alternator to the battery directly.......
i cooked my original ground wire when i had my audio and not a big enough alternator....
long story short and 700bucks later (due to a surge and a few cooked items)....... i have a 1 odd guage ground wire and i ran a 10 guage wire from the alternator to the battery directly.......
