alternator wiring question

[sqrlnts]

Quick question about my alternator wiring. I am running a GM 3 wire alternator with an EZ wire harness. I plan on connecting the white alternator exciter wire to T2. (not just jumpered to the alternator like in the picture).

My question is do I need to install the diode coming from T1 to the load side of the ignition switch like in the picture if I am using a HEI? I read it helps to eliminate engine run on.... Thanks in advance.

[starterman99]

yes ,when the alternator is charging there is a feedback through terminal 1 which will supply power back into the system.so even if you turn the ignition to off it will power ignition coil and not let the engine shut off.the diode will prevent this and protect the diode trio in the alternator from overload causing premature alternator failure.

[sqrlnts]

Originally Posted by starterman99

yes ,when the alternator is charging there is a feedback through terminal 1 which will supply power back into the system.so even if you turn the ignition to off it will power ignition coil and not let the engine shut off.the diode will prevent this and protect the diode trio in the alternator from overload causing premature alternator failure.

Thanks!
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[butchp]

While you guys are on alternators can I ask a question? I bought a 130 amp single wire alt. can it be wired like the non single wire and would there be an advantage to add the extra wires and diode.

[sqrlnts]

the shortest and most concise answer to your question is
http://www.madelectrical.com/electri...hreewire.shtml
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[mr48chev]

Originally Posted by butchp

While you guys are on alternators can I ask a question? I bought a 130 amp single wire alt. can it be wired like the non single wire and would there be an advantage to add the extra wires and diode.

That depends on how they did the single wire setup but I'd just leave it the way it is and count on having to gun the engine to energize the alternator if it doesn't otherwise start charging when you fire up the truck. I've seen them both ways and most of the single wire units i have seen are on diesel farm trucks that were converted with alternators from a local parts house when I was working on a dairy farm.

I'm not a big fan of the single wire units simply because hooking a regular Delco alternator up like the photo squirts showed is so simple and fool proof. The hardest part is soldering the diode in the wire. Massey Ferguson also stocks a diode that will work. The photo that Squirts used originated on a farm tractor board by the way. http://www.ytmag.com/cgi-bin/viewit....mall&th=789026

[butchp]

I talked to the tech. at powermaster today about the one wire alternator he said that when the article was written from Mad that the companys that made one wire alternators were converting std. alt. to one wire . The tec at Powermaster said if I attached the wire to the starter on the batt.location the alternator would sense the voltage drop and turn on. I am not trying to hurt the people at Mad by saying this, but the new alternators (Powermaster) will work without the senseing wire from the two prong plug. The amp gage wont work in this way of wiring.
I hope I did not offend anyone by this information.

[solidaxel]

When I read the MAD article I think I got a different idea on charging and sensing voltage drop not just exciting the alternator with a one Vs. a 3 wire