Is it ok to drive with the alternator unplugged? (1 Viewer)

[danthman114]

i was thinking about how my voltage regulator just took a dump and I limped home a few miles away, trying to keep the rpms low as possible. I was curious what would happen if I unplugged the alternator and just drove of what I had stored in the batteries instead of cooking my optima with over charging. would this be a bad idea?

 

[surfpig]

i was thinking about how my voltage regulator just took a dump and I limped home a few miles away, trying to keep the rpms low as possible. I was curious what would happen if I unplugged the alternator and just drove of what I had stored in the batteries instead of cooking my optima with over charging. would this be a bad idea?

You should be alright.

 

[AndyR]

I don't think the battery would last very long, like several minutes maybe before things started going dim.

Just based on what I have experienced driving with alternators that weren't charging.



-Andy

 

[danthman114]

I thought so but just wanted to check. I would hate to have to replace a $200+ battery too.

 

[danthman114]

I don't think the battery would last very long, like several minutes maybe before things started going dim.

Just based on what I have experienced driving with alternators that weren't charging.



-Andy

I have dual batteries and can combine them in an emergency. if I'm in the middle of nowhere and no cell service (which is most of the desert here) it could mean hiking a lot or not hiking very much. I would rather drive until it dies over hike until I die...

 

[AndyR]

Don't know if you would toast the batteries, good thing you have two.

You could maybe drive on one until it begins to die, then switch to the other. When both are drained, you could wait around for several hours, I think they might charge back up. But doing this repeatedly *might* toast the batteries.

But I'm no expert...good luck and godspeed!



-Andy

 

[dividedwood]

Don't know if you would toast the batteries, good thing you have two.

You could maybe drive on one until it begins to die, then switch to the other. When both are drained, you could wait around for several hours, I think they might charge back up. But doing this repeatedly *might* toast the batteries.

But I'm no expert...good luck and godspeed!



-Andy

Done just that with a buddy before. The alternator in his Range Rover died on our way back from Moab, so we swapped batteries. He made it another 30 miles or so (distance to nearest AutoZone) and the battery still had enough juice to start my truck when I put it back in...

 

[Dork]

Diesel swap! When my alternator died I continued driving for 3 more hours that day, stopping and starting the vehicle 3 or 4 times. Then drove it a couple more days around town until getting a replacement figured out.

 

[danthman114]

Diesel swap! When my alternator died I continued driving for 3 more hours that day, stopping and starting the vehicle 3 or 4 times. Then drove it a couple more days around town until getting a replacement figured out.

ok. ill do the swap. just let me have the money to do it! I would love a diesel

 

[Dave 2000]

The answers you get will vary enormously.

Running the engine with a good alternator disconnected can destroy it, as yours is already knackered it matters not.

The next question is a lot harder to answer accurately. Once the engine is started then your distance till it dies depends on many variables.

If the battery is old, the power available at the point the alternator failed, even the temperature has an effect.

A petrol engine would need around 30 amps to keep it running, so a typical well charged battery should give at least 3 hours driving, diesels at least double that. This assumes all other electrics are turned off. If you had a diesel, you could in fact remove the stop plunger, and then keep the engine running for as long as there is fuel available.

Note, the above does NOT apply to most modern petrol or diesels, there are so many electrics running that the ECU normally gives about 10 minutes before shutting down, this prevents damage to sensitive electronics.

Regards

Dave

 

[danthman114]

Don't know if you would toast the batteries, good thing you have two.

You could maybe drive on one until it begins to die, then switch to the other. When both are drained, you could wait around for several hours, I think they might charge back up. But doing this repeatedly *might* toast the batteries.

But I'm no expert...good luck and godspeed!



-Andy

the cool thing about jell cell batteries is you can get away with draining them and not much happen to them IF you charge them properly. ive had a red top in my jeep for shy of 10 years and its died from not being driven but always charges and holds. lead acid on the otherhand, will develop a memory in a way. it will never charge to its full potential once it dies and gets a partial charge and dies again...

 

[Qball]

It would work, I would check the battery first.

I replaced my alternator because I thought it was bad from fluctuation of voltage......it turned out to be my $300 diehard platinum 31 battery!

So I chalked the reman danso alternator as PM.

 

[Dave 2000]

the cool thing about jell cell batteries is you can get away with draining them and not much happen to them IF you charge them properly. ive had a red top in my jeep for shy of 10 years and its died from not being driven but always charges and holds. lead acid on the otherhand, will develop a memory in a way. it will never charge to its full potential once it dies and gets a partial charge and dies again...

Completely agree, I used the Optima range for years, never an issue...until Johnson took manufacturing to Mexico

Same as my electric engine cooling fan from a Lincoln MK VIII, OE Siemens units NLA, now made in Mexico...quality sucks! Now running a Merc PWM fan......windy city!

Regards

Dave

 

[danthman114]

it was my voltage regulator that bought the farm. my charge relay isolated the batteries and the voltage spiked up to 17v depending on rpm. after 202k miles, I would say it had a damn good run... got another reman denso from rock auto for 120 bucks... I might pick up another regulator to have as a spare to keep in the storage box...

 

[Dave 2000]

Unsure on your petrol version, but the diesel reg needs a decent soldering iron to fit it.

Regards

Dave

 

[bajaphile]

I have dual batteries and can combine them in an emergency. if I'm in the middle of nowhere and no cell service (which is most of the desert here) it could mean hiking a lot or not hiking very much. I would rather drive until it dies over hike until I die...

How are you in the middle of nowhere without service and able to post?

Since you have some sort of service, can you request a tow?

 

[danthman114]

How are you in the middle of nowhere without service and able to post?

Since you have some sort of service, can you request a tow?

IF I'm in the middle of nowhere. I'm on lunch right now...

 

[Dave 2000]

How are you in the middle of nowhere without service and able to post?

Since you have some sort of service, can you request a tow?

Come on now, try to keep up.

Regards

Dave

 

[danthman114]

Unsure on your petrol version, but the diesel reg needs a decent soldering iron to fit it.

Regards

Dave

I'm not sure if I have to solder anything. when I get home ill open the old one up and see. I don't think it requires it but I could be wrong...
however, being a former generator mechanic in the marines I learned many field expedient ways to solder. a good one but sloppy is heating up a screwdriver and then adding the solder. you often ruin the tool but it can get you out of a jam in an emergency...

 

[Dave 2000]

Yep BTDT. Most Bosch unuts are a couple of screws, the brush box and reg screw in as one, most Denso units need solder IME.

I do carry my old 80 amp unit in the trail spares box so more about quickness for ne.

Regards

Dave