Way to check if the regualtor and alternaotr is good?
11-01-2002, 03:11 PM
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Way to check if the regualtor and alternaotr is good?
OK, I have had an on-going saga with alternators for my 911. The place rebuilt it for the third time. The finaly replaced the stator (should have done this the first time) When it died. Last time I ran the car it was giving me a alternator light on when the car was running and and would dim as RPM's go up but would never go out. This means either
A. Bad alternator
or
B. Bad regulator.
Well, they had just put a new regulator in it during the second rebuild. Well, I took it back and they replaced the stator, I thought they were going to put a new regualtor on it as well but it looks like the same one.
What I want to know is there any way of testing the alternator and the regulator on your own without puting it in the car and using the light to trouble shoot.
A. Bad alternator
or
B. Bad regulator.
Well, they had just put a new regulator in it during the second rebuild. Well, I took it back and they replaced the stator, I thought they were going to put a new regualtor on it as well but it looks like the same one.
What I want to know is there any way of testing the alternator and the regulator on your own without puting it in the car and using the light to trouble shoot.
11-01-2002, 05:26 PM
#3
Technical Specialist
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I don't mean for this to sound like a wiseacre comment, however, after rebuilding your alternator 3 times and having to replace parts multiple times, wouldn't it be easier to buy a new alternator, which will have the integrated regulator? As I recall, you can get a new one for around $400, maybe a little more from Porsche (if discounted, of course), which would also have the Porsche 2 year warranty. Just a thought....
11-01-2002, 06:10 PM
#4
For your immediate needs, buy or borrow a voltmeter and connect it to the battery.
Open circuit voltage (engine OFF) should be around 12.7 - 13.0 volts. With the engine running at around 1500 rpm (do this with headlights and fan motor ON), the alternator output should be around 13.7 - 14.5 volts. If the voltage is low with the engine running, you have a problem in either the alternator, regulator, both of them or wiring (dirty, loose, corroded wire connections). Check the main battery cable connections/grounds as well.
Sherwood Lee
<a href="http://members.rennlist.org/911pcars" target="_blank">http://members.rennlist.org/911pcars</a>
Open circuit voltage (engine OFF) should be around 12.7 - 13.0 volts. With the engine running at around 1500 rpm (do this with headlights and fan motor ON), the alternator output should be around 13.7 - 14.5 volts. If the voltage is low with the engine running, you have a problem in either the alternator, regulator, both of them or wiring (dirty, loose, corroded wire connections). Check the main battery cable connections/grounds as well.
Sherwood Lee
<a href="http://members.rennlist.org/911pcars" target="_blank">http://members.rennlist.org/911pcars</a>
