[Resolved] 1996 850, Crank+No Start after battery recharge Topic is solved

[erikv11]

Snug should be good enough if the surfaces are pretty clean. You have good cranking so this is less of an issue but in the long run you want them clean, check it to rule it out.

[ToriWhite]

I would treat for LMS, then drive the car to the auto parts store and ask them to analyze the charging system with their little gizmo. Don't take the employee's analysis too verbatim, like don't make a decision on the spot based on what they say, but their equipment can give pretty useful information. See what it says.

Today I'm going to see if I can borrow my friends battery tester, and try and check the spark plugs.
I've always been skeptical of the LMS treatment, can motor oil do any damage putting it in the spark holes?

[erikv11]

Oil gets in the cylinders all the time, albeit at very low amounts. As long as you don't overdo it, like just 1 teaspoon, you are fine. I've done it a bunch of times. Use a baster or syringe is even better, to avoid the plug threads. Since you are pulling the plugs anyway, I would do it.

[ToriWhite]

Battery load tester said a "BAD" 8 volts, but this wasn't off a full charge, I had previously put 20 sec attempt in the night before. Topping it off and trying again ASAP, in the meanwhile I'm working on opening up the spark plugs.
Is 8 volts too low? I mean it's enough for the starter to crank, but does it not crank the starter with enough force?

[scot850]

I'm not an expert on Volvo electricals but most cars need a minimum of 9.5-10V to start and operate the injectors.

Neil.

[ToriWhite]

Fully charged battery load test: 10.5 volts and dropped very quickly below 10 volts over the duration of the test (5-7 sec)
The previous test was after one attempt to start (20ish sec on the ignition), under load was 8 volts. Everywhere I've read says it needs at least 9 volts to start the car, I'm thinking my battery isn't capable of holding a 9+ volt charge for more than a split second under the starters drain, would explain the multiple 'almost' engages I've had.
Read the battery code, did a lil research and found that the battery I'm using is at least 15 years old! (was shipped out by 2001!!)
All of this hubbub might just be the death throes at the end of this poor batteries long, long, life of service.
Am going to go buy a new battery tomorrow, I hope they let me on the bus with the battery, that can't be too dangerous right?
Will report back on if it works, and if not, will try the LMS cure, and hopefully I'll be able to finally end this headache!

[misha]

You would need healthy 12v in order to start the car.Fully charged battery have 12.7v and at 12.2v it's at 50% of capacity.
11.9 v is discharged battery!

[abscate]

It's really dead, Jim

[ToriWhite]

All this nightmare: turns out it's a bad fuel pump / relay.
I previously tested the fuel line to check if there was sufficient pressure, and I presumed that a li'l dribble paired with the sound of the motor turning on, was enough- but no, no it wasn't. This entire thing was the pump slowly dying on us, last time we tested it before the replacement, we got no pumping action at all, even when jumping the relay.
Replaced the pump ($150), and the relay ($50) because we hypothesized the bad relay is what caused the pump to start dying, and I'd rather buy a new relay now than a new pump next month
And, in our efforts of troubleshooting, replaced the distributor cap and spinner, and the battery. Really glad that I got to replace the battery, I have no idea how that thing carried me this far, but it for sure wasn't going to last another year.

Lessons learned: Thouroughly test your fuel line, dribbles and drabbles don't cut it, it's gotta be pressurized

[erikv11]

well .. huh. Thanks for posting up the full solution, really helpful to know and have it on here and searchable.