Battery or Alternator Diagnosis Help [1997 Volvo GLT Turbo]

Post by **1997volvo850** » 05 Nov 2017, 07:09

I've got a 1997 Volvo 850 with a 3-4 year old Bosch battery.

The current symptom is that I frequently can't start the car. For a while the car wouldn't start on first turn of key and by turning the key a few times it started up fine. I'm not sure if this points to a starter/key switch issue or this behavior is possibly due to weak battery.

The car runs fine once I jump start it. According to Robert's videos this points towards the battery.

When I take one of those LED alternator test units and connect it to the battery it lights up in the battery range - to 12.5 volts - and not up into the alternator range of 13-14 volts. This would point back at the alternator.

I suppose I could have a weak battery and under performing alternator.

So I'm wondering what to try next? Should I drive it to a store and have them test the alternator and battery? Any recommendations are welcome?

I understand getting a new/rebuilt alternator installed will be on the order of $400-500. Is this accurate for what to expect from local shop?

Any recommendations for purchasing a battery? Any brands to avoid. They seem to run around $150 for my vehicle.

Thanks in advance.

Post by **misha** » 05 Nov 2017, 08:31

You need 13.5-14.4v on battery terminals when engine is idling,with headlights,heater blower and rear demister ON.
Voltage drop test will tell you everything.

Post by **abscate** » 05 Nov 2017, 10:04

Estimate is about right

$200 for part retail
2 hours labor puts you into the $400-500 job range.

BeachWagon · Post by **BeachWagon** » 05 Nov 2017, 10:08

Sometimes a battery can fail in such a manner that it will show a lower voltage, even while the vehicle is running. The life expectancy of a common battery is 3 to 5 years so you are in the neighborhood of time where it is safe to assume it's time for replacement. Battery brand has never mattered much to me, since there are only a small handful of manufacturers that make many of the brands we see on shelves.

That said, yes it would be a good idea to go and have your battery load tested.

Post by **wizechatmgr** » 06 Nov 2017, 01:24

I'd drive it to a store that has the capability to test both battery and alternator while it is in the car. Call them ahead as I ran into a situation where neither local store was able to verify my existing alternator was bad when removed from the car due to equipment failures. At the moment I believe it to be a case of a low battery and a bad alternator - said testing will confirm or refute this belief.

As abscate said - it does take a solid 2 hours to swap that out - but at least the super hot days are gone. I would suggest buying a serpentine belt tensioner tool from HF or Advance in order to get the serpentine belt back on if you choose to DIY it. On mine there wasn't exactly a surplus of extra room to remove the alternator - it did come out the top but there was some elbow grease involved. It can be a bear to get the serpentine belt back on there - the $20 tool will save you many beers.

Post by **jreed** » 06 Nov 2017, 05:10

I agree with all the helpful tips above. This past summer I replaced the battery on my '97 855 GLT. Last summer I replaced the alternator ($276 from IPD). Also three years ago I replaced the positive battery cable that connects the battery to the starter.
Those three parts are the most likely contributors to the starting problems you described.
A battery load test will help determine if the battery is still good.
A voltage drop test between the battery terminal, the cable, the starer, and the alternator terminal will help determine if the cable or connectors are bad.

Battery testing:
viewtopic.php?t=81897

Cable testing:
Fabricate a positive battery cable diy

Post by **abscate** » 06 Nov 2017, 18:07

I've never bought that serpentine belt tool, a 14 mm wrench will work
That reminds me, return wisechatmgrs serpentine belt tool

Post by **tryingbe** » 07 Nov 2017, 05:59

#1. Get a $6 multimeter that gives you exact voltage reading.
https://www.harborfreight.com/7-functio ... 98025.html

Sounds you like have multiple issues.

Bad battery cables and / or bad battery. Battery test can only be done when the battery have charge. Auto parts store can charge and test the battery for you for free, use it.

Alternator is most likely fine. After you get the car running, then test for voltage drop between the battery and alternator with your new tool to see if the cables need to be replaced.

Herb Goltz · Post by **Herb Goltz** » 07 Nov 2017, 10:32

Check your alternator by measuring the output at the thick red wire on the back of the alternator-- you should see 13.7-14.1VDC if it is healthy (temperature and load dependent). If less, consider just replacing the voltage regulator/brush pack for about $40. It's a bit fiddly, but it can be done without removing the alternator from the car (there are threads here about how to do it-- I did mine a few years ago, and have done so on a number of other cars too).

I have had excellent luck with buying used batteries at a local wrecking yard-- $35 with a 2 year replacement warranty. As others have suggested, have yours load tested-- it is the definitive test. The advice on voltage drop tests is spot-on-- make sure you test the positive, negative and B+ cables.

Post by **1997volvo850** » 14 Nov 2017, 09:59

My independent took a look at these charging/starter issues during visit for inspection.

The positive cable was not functioning properly. Is this due to internal corrosion? They chopped off the positive connector and installed a new connector. He said this gets hot when this problem is happening. I never put my hand on the positive cable connector but will keep in mind when my car turns 30.

The starter (New Bosch starter a few years ago) still had issues so they replaced the starter. New starter did no better.

** The main ground cable to engine was gone and braided ground behind engine above turbo was basically dust. ** They replaced the ground and replaced my original starter and car starts right up. I guess the ground cables are something to check on these old cars. They can definitely make the starter seem flaky.

Would failing ground impair engine operation? Car ran ok once started but didn't seem to have much energy (oomph). Now it seems to run much stronger. Of course this could all be in my head.

They told me my alternator was not putting out as many amps as they expected. Not sure if there is something to do preemptively. They indicated my Bosch battery was a little weak and popped in a spare I had from a Kia that went to car heaven too soon.

Thanks for all the feedback!