The alternator replacement thread, Fixed! |
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The alternator replacement thread, Fixed! |
VaccaRabite |
Aug 12 2018, 07:07 PM
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#1
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En Garde! Group: Admin Posts: 13,456 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
Waiting on the side of the road for a flatbed to take me home.
Engine ran great. Charging system not so much. Driving along. Lights started going dim. Car started bucking. Only 5 miles to home but it wasn’t going to make it, and no shoulders to pull over safe on the little farm roads. So I pulled into a spot I knew of and shut it down and parked it and now I wait. McMark had said earlier he wasn’t sure about the charging system. But the alt light was not on and no issues before now. So. What’s the alternator I need to buy? Maybe a new VR as well? I guess I should test the battery and make sure it’s okay too. Zach |
VaccaRabite |
Sep 7 2018, 02:14 PM
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#2
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En Garde! Group: Admin Posts: 13,456 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
I got a new battery.
Not really any change over the smaller race battery. So I started playing with the collection of VRs I have recently collected. Depending on what VR I used, at idle I was seeing a range from 12.3 volts to 13.6 volts. The best results were from a hella solid state VR and an unamed adjustable solid state VR. With headlights and driving lights on, I’m showing 12.5 at the battery with the better VRs at hot idle. The voltage still drops when the engine revs, and sits at about 12.3-12.5 volts at 4K. If I short DF and D+ voltage DOES rise with rpms, and quickly goes up to 17-18volts. I have gone through all my grounds and currently see 0.000 ohms resistance anywhere. No resistance between engine case and negative battery terminal. None between alternator and engine or alt and body. My measurements from the battery and the voltmeter on the ECU are different by a volt (ECU sees slightly less voltage then the battery is showing). I’m left thinking this is just how my car is, and I DO NOT like it. I’m totally stumped, and have run out of things to replace. I think my car is probably fine to drive during the day, but I am afraid to drive it anywhere at night. Help? @spoke @clayperrine @mcmark PS. I just reread Spoke’s last post and still need to measure voltage between D- and the body. I’ll do that tonight. Now I’m off to the hospital to give comfort to mom. Zach |
worn |
Sep 7 2018, 04:26 PM
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#3
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can't remember Group: Members Posts: 3,156 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
I got a new battery. Not really any change over the smaller race battery. So I started playing with the collection of VRs I have recently collected. Depending on what VR I used, at idle I was seeing a range from 12.3 volts to 13.6 volts. The best results were from a hella solid state VR and an unamed adjustable solid state VR. With headlights and driving lights on, I’m showing 12.5 at the battery with the better VRs at hot idle. The voltage still drops when the engine revs, and sits at about 12.3-12.5 volts at 4K. If I short DF and D+ voltage DOES rise with rpms, and quickly goes up to 17-18volts. I have gone through all my grounds and currently see 0.000 ohms resistance anywhere. No resistance between engine case and negative battery terminal. None between alternator and engine or alt and body. My measurements from the battery and the voltmeter on the ECU are different by a volt (ECU sees slightly less voltage then the battery is showing). I’m left thinking this is just how my car is, and I DO NOT like it. I’m totally stumped, and have run out of things to replace. I think my car is probably fine to drive during the day, but I am afraid to drive it anywhere at night. Help? @spoke @clayperrine @mcmark PS. I just reread Spoke’s last post and still need to measure voltage between D- and the body. I’ll do that tonight. Now I’m off to the hospital to give comfort to mom. Zach After a lot of trying along similar lines I bought about six different voltage regulators and found that they pretty much all tended to undercharge. Especially with lights on. I ended up purchasing an adjustable regulator and that solved the problem. Now I have several extra alternators and other electrical system parts that I swapped out along the way. Can’t tell you how nice it is to be able to turn the switch and see about 13 and a half volts going in, plus or minus a bit. My regulator came from a site oriented towards Volvo 1800s. Hope it works for you soon. |
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