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Alternator Help
I'm desparetly trying to get my race car finished and have run into a problem. I have a 901 alternator shroud/housing with a Bosch 0 120 400 725 alternator which is only putitng out 12v. It has never run in the car before.
So, I'm looking to replace the alternator and have a few questions. Does this alternator have an external voltage regulator? If so, there is not one installed. So would adding one solve my problem? If I upgrade to a later alternator which one would be best? TIA, John
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1985.5 944 GTS |
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Does your alternator have a terminal on the back labeled "DF?"
And what is the EXACT casting number on your fan housing?
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'66 911 #304065 Irischgruen ‘96 993 Carrera 2 Polarsilber '81 R65 Ex-'71 911 PCA C-Stock Club Racer #806 (Sold 5/15/13) Ex-'88 Carrera (Sold 3/29/02) Ex-'91 Carrera 2 Cabriolet (Sold 8/20/04) Ex-'89 944 Turbo S (Sold 8/21/20) |
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Housing # 901 106 10105R
Alternator terminals B+ B+ D- DF D+
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Ok, now we are making progress.
You have a late 901 fan housing, probably off a 2,7, and an externally regulated Bosch Alternator. You say there's no external VR installed, which is why your alternator isn't putting out any voltage. So you should buy a Bosch external regulator from our host here and install it, hook everything up correctly and you should get 14V output voltage from the alternator. I would not waste time looking for a later alternator as they are heavier, require the use of a different fan housing and they have internal VRs, which are exposed to engine heat, which isn't good for them. I would stick with what you have and get the Bosch VR and hook it up correctly.
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'66 911 #304065 Irischgruen ‘96 993 Carrera 2 Polarsilber '81 R65 Ex-'71 911 PCA C-Stock Club Racer #806 (Sold 5/15/13) Ex-'88 Carrera (Sold 3/29/02) Ex-'91 Carrera 2 Cabriolet (Sold 8/20/04) Ex-'89 944 Turbo S (Sold 8/21/20) |
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Thanks for your help John.
How does it get wired and where should I put it? It is a full race car so there is no wiring except the red, blue and ground goung to the alternator. John
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1985.5 944 GTS |
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If it were me, I would put it on the parcel shelf inside the car where you would mount speakers.
Retrofitting a 69-73 MFI engine to a 1966 carb'd 911? It goes without saying that you should use aviation-grade wires, a minimum of 16 AWG, and make sure you insulate everything and route all wires where they will not chafe or short out. If you make a mistake you could very easily burn the car to the ground, so be careful.
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'66 911 #304065 Irischgruen ‘96 993 Carrera 2 Polarsilber '81 R65 Ex-'71 911 PCA C-Stock Club Racer #806 (Sold 5/15/13) Ex-'88 Carrera (Sold 3/29/02) Ex-'91 Carrera 2 Cabriolet (Sold 8/20/04) Ex-'89 944 Turbo S (Sold 8/21/20) |
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