How far on a dead alternator? My results

[fdcg27]

The '99 Legacy has needed an alternator for the past six months.
Until Sept 20 or so, as long as the car wasn't idled a lot and was actually driven some distance at speed, there was no problem.
On Sept 20, older son, who I'd just given the car to the previous day so that I could replace the master cylinder of the Focus he'd been using had the Subie die while in the early stages of his then hundred mile commute to work.
His younger brother bailed him out and he continued on his way to work in the '02 Accord. Younger son called the number on the car's insurance card and got the Subie towed to his place for free. Emergency road service is maybe two bucks a half on our insurance and has always been worth every penny.
I fixed the Focus, drove it to older son's new abode close to work and gave the '02 Accord back to younger son.
Meanwhile, the Legacy sat in the parking lot of younger son's apartment building.
Time to bring it home and fix it.
I got the battery out of it and brought it home to charge.
Yesterday, we drove down to younger son's place and I installed the fully charged battery.
I made it forty miles before the old Subie died, with wife following in the '12 Accord.
This was but eight miles shy of our house.
The wife and I drove home and I removed the battery from the BMW.
We drove back to the stuck Subie, I slapped in the BMW's battery and I drove the Legacy the rest of the way home.
I parked it in the yard and put its battery on the charger from around six yesterday to around five today.
I stuck the battery back in the Legacy and started it and moved it to a convenient spot in the driveway.
Now I just need to slap in the alternator I've bought from Rock.
Anyway, you can apparently drive a '99 Subaru Legacy about forty miles with no alternator output.
YMMV.

 

[eljefino]

You should have put a HF 2-stroke generator in the trunk with a charger rigged up!

 

[fdcg27]

Originally Posted By: eljefino
You should have put a HF 2-stroke generator in the trunk with a charger rigged up!

A better cute reply might have been to bring up how far you can drive a W123 diesel with no alternator output.
I've had a couple and so have you so you know what I'm saying.

 

[JHZR2]

Originally Posted By: fdcg27
Originally Posted By: eljefino
You should have put a HF 2-stroke generator in the trunk with a charger rigged up!

A better cute reply might have been to bring up how far you can drive a W123 diesel with no alternator output.
I've had a couple and so have you so you know what I'm saying.


Certainly from DC to Philadelphia, including a major beltway traffic jam and some headlight usage!

 

[dishdude]

Just out of curiosity, why didn't you change the alternator out before it completely died? Especially considering the car was being used on a hundred mile commute.

 

[dlundblad]

I ran into this issue this evening with my brother in his S10 Blazer. We were about 40 miles from home and his battery light kicked on. For giggles, we pulled into an Oreilly's and had it tested. It was the alternator.

I doubted we'd be able to make it home. Plus we needed the headlights. Took about a half hr, but I was able to replace it in the parking lot.

They had a decent selection of tools they let me borrow too.

 

[mjoekingz28]

Originally Posted By: JHZR2
Originally Posted By: fdcg27
Originally Posted By: eljefino
You should have put a HF 2-stroke generator in the trunk with a charger rigged up!

A better cute reply might have been to bring up how far you can drive a W123 diesel with no alternator output.
I've had a couple and so have you so you know what I'm saying.


Certainly from DC to Philadelphia, including a major beltway traffic jam and some headlight usage!




Are there carbureted diesels out there? Î think big rigs have for some time been fuel injected since there is no throttle butterfly. I am not too sure of how it works, but a diesel needs alot of fuel pressure to operate the injectors.....so some electricity?

 

[Kestas]

It happened to me twice. Each time I'd get about 20 miles before the car died.

 

[Chris142]

Originally Posted By: mjoekingz28
Originally Posted By: JHZR2
Originally Posted By: fdcg27
Originally Posted By: eljefino
You should have put a HF 2-stroke generator in the trunk with a charger rigged up!

A better cute reply might have been to bring up how far you can drive a W123 diesel with no alternator output.
I've had a couple and so have you so you know what I'm saying.


Certainly from DC to Philadelphia, including a major beltway traffic jam and some headlight usage!




Are there carbureted diesels out there? Î think big rigs have for some time been fuel injected since there is no throttle butterfly. I am not too sure of how it works, but a diesel needs alot of fuel pressure to operate the injectors.....so some electricity?
no such thing as a carbureated diesel. The newer ones use electric injectors. The old ones were purely mechanical and would run forever without power. My f250 has an electric solonoid that cuts the fuel off so it requires power.not much.a few volts will keep it open

 

[BHopkins]

In 1993 I think, I was moving from Utah to South Carolina, driving a 1982 Olds Toronado. Somewhere on I-80 in Wyoming, I had a fan belt fail. Yup, the one that drove the alternator. Now, if you have driven through the vast expanse of the least populated state in the nation, you know that towns are far apart. So I had no choice but to see how far I could drive on battery only. I shut the AC and radio off so only the ignition was pulling battery power.

Made it 45 minutes to a gas station sitting right off the interstate. Nothing else in sight. They charged me less than $20 to install a new belt. Car still had enough juice in the battery to turn over without a jump start.

So, for a big GM V-8 with a Series 78 battery and all accessories shut down, no lights, it's greater than 45 minutes to a dead battery.

 

[Colt45ws]

Yeah, the older diesels just had a mechanical injector pump on the engine that did all the work of pressuruzing the fuel, and sending it out to the individual injectors.
If you look at a old diesel, you'll see the individual injector lines going down to a device on the engine. Sometimes looks like a distributor the fuel lines come off of. Same idea as one, squirting fuel into each one to fire the engine.
Some times, like Chris said, just a cutoff solenoid that doesn't take nothing for wattage to hold open.
Modern diesels still use a mechanical pump (the pressures are really high) but go into a manifold and the injectors are fired by the PCM.
Thats where "Common Rail diesel" comes from since the fuel is fed to a common rail instead of individual fuel lines.

 

[fdcg27]

Better yet, on an old Mercedes diesel, the fuel shut off is vacuum operated, with vacuum being used to shut fuel flow down, so you need no electricity at all to run the car.
Vacuum with a diesel?
Yep, Mercedes used a vacuum pump and vacuum powered the brake booster and central locking system as well.

 

[SwampSurvivor]

Originally Posted By: Colt45ws
Yeah, the older diesels just had a mechanical injector pump on the engine that did all the work of pressuruzing the fuel, and sending it out to the individual injectors.
If you look at a old diesel, you'll see the individual injector lines going down to a device on the engine. Sometimes looks like a distributor the fuel lines come off of. Same idea as one, squirting fuel into each one to fire the engine.
Some times, like Chris said, just a cutoff solenoid that doesn't take nothing for wattage to hold open.
Modern diesels still use a mechanical pump (the pressures are really high) but go into a manifold and the injectors are fired by the PCM.
Thats where "Common Rail diesel" comes from since the fuel is fed to a common rail instead of individual fuel lines.


My father drove from NYC to Utica, NY in a Peterbilt with no alternator. It was an 80s mechanical injection diesel truck. Had no head lights when he got back!

 

[eljefino]

Originally Posted By: fdcg27
Better yet, on an old Mercedes diesel, the fuel shut off is vacuum operated, with vacuum being used to shut fuel flow down, so you need no electricity at all to run the car.
Vacuum with a diesel?
Yep, Mercedes used a vacuum pump and vacuum powered the brake booster and central locking system as well.


I've read that my automatic transmission will even roll-start said diesel if I get it up to 30 mph. I tried 15, no go, there.

On a clear day, it's literally only the fuel gauge, water temp, oil pressure and RPM that use any power. Speedo is mechanical.

 

[Vikas]

About a foot or so with older (eighties) Hondas! When the alternator died, the fuel flow to the carburetor got cut off. The cut off was bypassed during cranking. So you could start the car but as soon as you tried to move, it would stall. You could restart it again and repeat the loop.

 

[RoadRaceJosh]

Hi! I've known about a problem with my car for 6 months! I lent it to my kid and he got stranded. Does anyone give 2-shhits how far I was able to drive the car without fixing the problem? Anyone, anyone, Beuller?

 

[SeaJay]

I had an old chevy out on a 100+ mile trip. Somewhere along the line no more than halfway along the lights and horn started dimming. Not sure when the alternator slowed down and where it stopped completely, but did make it to my destination. A jump in the morning got it started and driveable to a service station.

 

[cptbarkey]

considering how easy it is to change an alternator on a subaru, i dont understand how one could torture themselves for that long. reminds me of the guy who kept his soiled underwear for a couple years and posted occasional update pics on reddit. look it up.

 

[kschachn]

Cool story bro.

Originally Posted By: Joshua_Skinner
Hi! I've known about a problem with my car for 6 months! I lent it to my kid and he got stranded. Does anyone give 2-shhits how far I was able to drive the car without fixing the problem? Anyone, anyone, Beuller?

 

[fdcg27]

The OMs of old MB cars gave explicit instructions on how to tow-start the car if needed.
Get your old diesel running and you were then on the road to wherever.
I'd imagine that modern liability concerns would rule any such instructions out of anything printed by any maker these days.