Voltage and power dropping.

Gotta love that wiring . . .
SpecialTool

Re: Voltage and power dropping.

Post by SpecialTool »

Lt,
That light indicates the charging system is not working, with an OE alternator. I'm not sure if it still functions with the 95A conversion as I have no experience with that system. There is a fuse in the OE setup that will cause the light to go on if it becomes open.
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seabeelt
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Your car is a: Fiat Spider - 1971 BS1
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Re: Voltage and power dropping.

Post by seabeelt »

The light is " on" when the car is off as normal. Once the car starts the light goes off........... Unless you hit 6500 rpm..... Hmmmmmmmm
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
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toplessexpat
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Re: Voltage and power dropping.

Post by toplessexpat »

So the light works as normal for OE with a 95A upgrade. Could the 6500 rpm be associated with something coming slightly disconnected? i.e. There's a loose connection that only shakes intermittent enough to matter at that rpm? I'm assuming that you've patched out the Voltage Regulator - check there?

A
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seabeelt
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Re: Voltage and power dropping.

Post by seabeelt »

Yup, old voltage regulator out of the system (and car for that matter). Actually called Mark's shop just to make sure I had the wires connected correctly before starting the car after installation. These small anomalies bug me..... Dash and bulbs have all been gone over a couple of times. Shouldn't think the alt was turning too fast at that rpm speed......
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
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toplessexpat
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Re: Voltage and power dropping.

Post by toplessexpat »

How about putting a meter on the line that comes out the back of the alternator, driving and seeing if there's drop?

A
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seabeelt
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Re: Voltage and power dropping.

Post by seabeelt »

Alternator definitely not charging. :shock: :shock: :shock: Went out this evening and barely made it home. Last mile with no lights and car barely enough juice on the new battery to get up the drive.
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
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81SPIDERMATT
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Re: Voltage and power dropping.

Post by 81SPIDERMATT »

voltage regulator ?????
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seabeelt
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Re: Voltage and power dropping.

Post by seabeelt »

It's a new 95amp alt from Mark
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
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seabeelt
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Re: Voltage and power dropping.

Post by seabeelt »

Heck, I don't know what's going on. Took everything apart. Took the alternator up to AutoZone for a quick test. No part number so the guys were kind enough to poke around in their system to find something close with the same plug set. Alternator passed using three different models. So OK bring it home, reinstall, double check belt, all electrical connections, applied more die-electric grease to all the connections. Fire it up. Charging like a champ. Gonna take it for another drive in just a bit....... We will see what happens


Different alt story.... On the way to Autozone, truck gauges go whacky, check gauges light comes on, battery charge indicator is all the way to the left at discharge. Hmmmmmm. Have the AZ guys check that one while running. Bad alternator :shock: , so I get a new one while there, old one still under warranty. Swapped that one out once I got home. Took about 15 minutes


Seems like today was alternator day all around
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
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toplessexpat
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Re: Voltage and power dropping.

Post by toplessexpat »

Do you have a personal electromagnetic field around you that messes up electrics? ;)
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Re: Voltage and power dropping.

Post by RRoller123 »

salt air?
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Re: Voltage and power dropping.

Post by seabeelt »

Electrical Gremlins..... The have a nest near the garage with many tunnels and only come out a night
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
majicwrench

Re: Voltage and power dropping.

Post by majicwrench »

Like I said way back when, your charging system is not working, at least some of the time. If belt and connections ok, you need to replace that alternator. Getting alt tested at AZ is almost pointless. So it passed. Sitting on a bench with a couple of kids trying to figure out how to hook it up. At times,it does not work in car, that is what matters.
Keith
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Re: Voltage and power dropping.

Post by seabeelt »

I did notice some belt wear and the belt face looked slick. Had the normal 3/8 inch play when I took it off. Its a little more snug now. I suspect there was/is some slippage. Drove quite alot Sunday and still getting good voltage readings... I will keep checking. I will replace the belt as soon as I can
R/
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
majicwrench

Re: Voltage and power dropping.

Post by majicwrench »

Best way to check belt tension. If alt has fins, easy, with engine off (duh) grab fins with hand see if yoiu can turn it. If you can turn alt fins/pulley, belt too loose.
If alt doesn't have fins, with engine off (duh again) fit a socket over shaft of alt, a lot of are 10mm hex, not sure on fiat. Use ratchet to try to turn alt. If alt pulley slips on belt, belt too loose.

3/8 play is really a subjective measurement that means very little. See if it slips.
Keith
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