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upgrade charging system?

Help, Advice and DIY Tutorials on Volvo's P80 platform cars -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, including 850 R, 850 T-5R, 850 T-5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

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shegarty
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Year and Model: 1998
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upgrade charging system?

Post by shegarty »

Hi folks, I just installed a new subwoofer to help with low end bass. It was nothing outrageous (a single 12" 300W rms unit) but I am concerned that I might be stressing the charging system. At higher power levels the lights (headlights and dash) dim slightly. Alternator is still putting out about 13.7V during this time (13.8/9V otherwise). Should I be looking at upgrading the alternator or wiring? What options are available?
98 S70 T5 SE 298k km (daily)
87 740T sedan (current project)
previous - 90 745T; 94 855 T5

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abscate  
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Post by abscate »

There were both 80 Amp and 100 Amp options for the 1998 year - check and see which one you have to see if the easy upgrade path is there for you.

About $200 plus core of $100 and you need to bring your pulley over to the new one, too.
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A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 XC90-in-Red
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shegarty
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Post by shegarty »

abscate wrote: 20 Nov 2019, 09:39 There were both 80 Amp and 100 Amp options for the 1998 year - check and see which one you have to see if the easy upgrade path is there for you.
Am I looking for specific markings on the alternator itself?
98 S70 T5 SE 298k km (daily)
87 740T sedan (current project)
previous - 90 745T; 94 855 T5

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abscate  
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Post by abscate »

The output is usually labelled on the voltage regulator - I think you can see it with a mirror and light without removing anything,
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 XC90-in-Red
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misha
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Post by misha »

With 100A alternator you don't need an upgrade.
I don't think that you would need an upgrade even with 80A one.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

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98RedV70GLT
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Post by 98RedV70GLT »

Get a capacitor.
98 V70 GLT
90 Q45

shegarty
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Post by shegarty »

Looks like I have the 100A version. I am thinking that it might be worthwhile to check connections and clean them up, maybe upgrade the wiring when it warms up a bit. I have also noticed a dip in dash lighting when the malfunctioning SAS tries to engage as well as when the A/C compressor kicks on. Hopefully its not a sign of the alternator or regulator on its way out as this has been happening now for 5+ years.
98 S70 T5 SE 298k km (daily)
87 740T sedan (current project)
previous - 90 745T; 94 855 T5

xHeart
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Post by xHeart »

1997 Volvo 850 NA is consuming battery. Found recently installed (October 2019) new battery dead after few days of not driving.
The car started fine after the battery was on trickle charger overnight. Weather temp is between 35º - 55ºF.

The original Volvo 100A alternator is charging at 13.3V during a normal drive with radio and heater running. What to look for?

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abscate  
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Year and Model: 99: V70s S70s,05 V70
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Post by abscate »

xHeart wrote: 24 Dec 2019, 11:38 1997 Volvo 850 NA is consuming battery. Found recently installed (October 2019) new battery dead after few days of not driving.
The car started fine after the battery was on trickle charger overnight. Weather temp is between 35º - 55ºF.

The original Volvo 100A alternator is charging at 13.3V during a normal drive with radio and heater running. What to look for?

Happy holidays!
Current drain - its time to play pull the fuse, measure the current.

An old Analog (analogue in the UK) meter is best for this - superior to digital in oh so many ways.

You should be well under 50 mA (0.050 Amps) drain on a Volvo sitting still, all doors and glovebox closed.
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 XC90-in-Red
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misha
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Post by misha »

xHeart wrote: 24 Dec 2019, 11:38 ...The original Volvo 100A alternator is charging at 13.3V during a normal drive with radio and heater running. What to look for?
B+cable from battery to starter(usually).
It should be 13.8-14.2v at idle with headlights,heater and radio ON.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

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