81 alternator
Thread Starter
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
81 alternator
my original alternator was getting a bit sad so i have replaced it with a new bosh alternator that has a constant 150 amps. the old alternator had a 2 plug system for a red and a brown wire. this new bosh alternator only has a single plug coming out so what can i do to adapt to the new alternator?
Le Mans Master
Joined: Jan 2001
Posts: 6,679
Likes: 1,364
Might want to tell us what new alternator you got....
Who made it? What is it for?
I recently repalced my 94 amp 12si with a CS-144 that puts out up to 150 amps (according to NAPA website). I would recommend something like that, but to assist we really would need to know what it is that you bought.
I recently repalced my 94 amp 12si with a CS-144 that puts out up to 150 amps (according to NAPA website). I would recommend something like that, but to assist we really would need to know what it is that you bought.
Thread Starter
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
yeah your right . i should have given some pics or a lil bit more info. here it is. i put a red arrow to the different style of clips that im talking about. the first pic is obviously the wiring and the second pic is the new bosch alternator with its single plug system and the last pic is the original 81 alternator with its 2 plugs that suit the wiring in the first pic.
Thread Starter
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
what are the problems? being where i am i dont have many options to alternators to suit a corvette. this is the closest thing i could get as far as mounting positions and all that with good amps.i guess an auto electrician will know what to do.
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
Get a wiring diagram from Bosch. It could be that all you need it to connect the brown excite wire to that terminal, but I don't know for sure.
I too am also curious what problems occur with 1-wire alternators? There are a LOT of marine, construction, and farm equipment with 1-wire alternators.
I too am also curious what problems occur with 1-wire alternators? There are a LOT of marine, construction, and farm equipment with 1-wire alternators.
Racer
Joined: Mar 2005
Posts: 473
Likes: 2
From: Champlin Minnesota
Last edited by davidm_comp; Sep 26, 2007 at 10:51 AM.
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Drifting
Joined: Aug 2007
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I looked at the schematic for the 81. The red and brown wires are marked as V and L and both feed power back through the harness to different electrical components. I don't know what the W stands or on your replacement. Is the second smaller post with smaller nut marked?
My guess is that MAY be the equivelant of L (brown) leaving W (red)
But... a guess is a guess. You should have gotten some paperwork with the new one. Hook it up, start the engine and put a volt meter on your W connection (and the case to get a volt reading) and then do the same with the smaller post (without the red and brown wires connected of course)
Nonetheless.. these dont appear to be 1 wire jobbies. The heavy wire on post naturally goes back to the battery and the black wire should be a ground
My guess is that MAY be the equivelant of L (brown) leaving W (red)
But... a guess is a guess. You should have gotten some paperwork with the new one. Hook it up, start the engine and put a volt meter on your W connection (and the case to get a volt reading) and then do the same with the smaller post (without the red and brown wires connected of course)
Nonetheless.. these dont appear to be 1 wire jobbies. The heavy wire on post naturally goes back to the battery and the black wire should be a ground
yeah your right . i should have given some pics or a lil bit more info. here it is. i put a red arrow to the different style of clips that im talking about. the first pic is obviously the wiring and the second pic is the new bosch alternator with its single plug system and the last pic is the original 81 alternator with its 2 plugs that suit the wiring in the first pic.
Last edited by pbcanney; Sep 24, 2007 at 11:29 PM.
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
1-wire alternators work well for vehicles with short simple wiring, like tractors. They do not work good when you have long wiring(resistance in length), lots of high drawing accessories (electric fans, fuel injection, amps, etc.). The reason they don't work as well is because they don't have a remote sensing line, this line measures what the voltage is at your main power junction and tells the voltage regualtor to adjust voltage output to maintain a ~14.5 voltage at that junction, where as a 1-wire keeps a steady 14.5 at the back of the alternator, and your main junction only is getting 13, and by the time that gets to your headlights you might only have high 11s. Check out this site, has tons of good reading material on chevy charging systems: http://www.madelectrical.com/electrical-tech.shtml
