Alternator "Troubleshooting" [97 850] Topic is solved

[ToriWhite]

Short Version:
Jumped a 1-year-dead volvo on stale gas, it runs as good as expected; except for a concerning, low pitched whine from near the alternator and belts. Then the whole thing dies- battery dead.
Sure it sounds like a dying/dead alternator.. sure it looks like what jumping a dead alternator would look like.. but is there any way.. any shred of hope this isn't the $200 + hours of labor nightmare of a dead alternator?

Detailed Version:
Volvo receives new belts and pulleys- the whole kit from FCP
Volvo throws P0410: something to do with the smog air pump, (probably) unrelated- theoretically doesn't affect drivability.
Volvo sits, undriven for about a.. year? Battery dies, obviously.
I go to jump it today, Jumper cables are where they should, Volvo's ground is some nut on the engine block near the throttle cable. Juice comes on enough for dashboard clock, bright indicator lights- Gives one rev, spark flies from grounded nut and everythings black- no lights or anything
Rearrange jumper so black's on the negative terminal- dash fades in, all looks good and it starts.
The engine sounds, different.. but after sitting for a year, I bet its just the cobwebs burning up, or that it's the sound of burning the stale gas that's sat there all that time.
After a minute, engine revving sound kinda normalizes.. but there's another sound to the lower left of the engine, a low pitched whine, or rubbing sound..
It sounds like a less intense version of what Omega239 ran into and recorded a while back... < viewtopic.php?t=56275 >




... after disconnecting the cables, I idle and rev it for a couple minutes. I notice the idle slowly climbs to 1.5k RPM.. when suddenly, no struggle- no fade- the entire thing blacks out like I turned the key.

Is there any hope? Or am I gonna have to grind my teeth on biting another bullet to keep this ol' thing running?

[RickHaleParker]

The severely discharged battery may be working the guts out of the alternator (pushed to maxium output). Put the battery on a battery charger for at least 72 hours, then try again.

When the battery charger indicates fully charged, disconnect charger, wait 20 minutes, then reconnect charger. Repeat until it only takes a few minutes for the charger to get back to fully charged. On the first run, the charger may never reach fully charged you will need to reset by disconnecting the charger wait then reconnect.

Else, you could swamp the battery with one that is fully charged and in known good condition.

[abscate]

Get a new good battery in it. If that battery sat for a year, its a paperweight

After a minute, engine revving sound kinda normalizes.. but there's another sound to the lower left of the engine, a low pitched whine, or rubbing sound..

Left of engine or left looking backwards, aka right of engine?

[ToriWhite]

Else, you could swamp the battery with one that is fully charged and in known good condition.

I do have a working vehicle at my disposal, but it’s a 2010 Honda CRV..
AFAIK car batteries basically operate at the same 12-14v range, and their major difference is dimensions for CCA / engine bay fitment.. I’m not gonna Drive with a 2010 battery, but I wonder if I set it loosely in the bay and hooked up the terminals; if it could help me diagnose this without blowing up...

Left of engine or left looking backwards, aka right of engine?

Left of engine from looking into it, from an open hood. Same area in the linked video- only audible from outside with an open hood, everything sounded fine inside w/ door closed.

I don’t know what would cause an alternator to die except old age or seizing from ice or something. It is old, but I struggle to think it’s seized and burnt out, on account it doesn’t get cold enough to snow over here. Could it have seized just sitting for a year?

Boy, I’d love if this could just be a bad battery.. sure it’ll cost about the same- but a battery swap sure is easier to perform than installing a new alternator!

Going to do some reading to see if I can diagnose the paperweightedness with a standard multimeter before doing a diagnostic transplant from the Honda. Even before then, the local autozone/oriellies offers a free battery diagnosis (but I’m also pretty sure it’s just a gimmick where they say all batteries are bad, to sell their own)

[ToriWhite]

From initial research: Seems most batteries are interchangeable; as long as you’re not downsizing. Some people upsize in cold climates for higher CCA- but upsize too far and alternators going to struggle to push juice into it. Volvo 850’s a size 47, Honda CRV’s a 51- I wouldn’t want to drive on that for extended periods- for the alternators sake- but for doing diagnostics? A fully charged 51 theoretically shouldn’t strain the alternator, and could be used for diagnosis.. in theory, that is

[850oldschool]

You'll want a multimeter in addition to a fully charged battery. It's really tough to effectively diagnose charging system problems without knowing what the voltage is.

[ToriWhite]

Just to wrap this mystery up for any johnny-come-lately's who find this in the future: Thankfully- it was my battery that was bad. That sound recorded in Omega's video, that I heard as well is the sound of a straining alternator fighting to pump juice into a battery that just won't have it.
Lucky me, new batteries are a lot cheaper than new alternators - and a little easier to replace, too!
Lesson learned, Take your volvo out at least once a week! Make it an excuse to get fresh air and go on a walk or something! It'll save you headache in the future!

[scot850]

Glad you got to the bottom of the issue. I mentioned I had a strange issue with my car recently and it was due to a bad cell in the battery, New battery resolved it. Likewise, glad that was all it was.

Neil.

[abscate]

The severely discharged battery may be working the guts out of the alternator (pushed to maxium output).

It is increasingly apparent that Mr RHP is indeed samurai - and I don't mean Suzuki.

Thank you for follow up, OP