Increased PSI resulting in engine working harder? Discovered Dent in oil pan

[theholycow]

Originally Posted by *************

If you get that battery charger which I highly recommend because it's a "smart" charger unlike the sears diehard garbage
{...}
Another FYI is that MOST battery chargers won't charge a battery with a voltage less than like 7v because that causes it to think you've either got the wrong battery hooked up or that there isn't a battery hooked up at all. The solution to this is to hook up another battery with proper voltage (like 12v) in parallel to the battery needing to be charged and then charge with this setup for like 2 hours, then disconnect the battery that doesn't need to be charged and continue with charging..

I've recovered batteries with voltages as low as 0V back to perfect working order again, just be patient and it should work out.
{...}
I've charged well over 30 car batteries, about half of them with a battery voltage less than 3V. Your battery is obviously not as low as 3v but it's more than likely fully discharged (less than 11.8V).

I didn't know it was even possible to buy dumb chargers anymore, except for really expensive, large, heavy shop models. I've been wanting a dumb charger for a while because my damned smart chargers refuse to charge batteries that I think can still be revived.

I considered trying what you suggest with hooking up another battery but I was afraid it could destroy the other battery. Since it worked for you I may give it a try. I have a few batteries that may be revived by it.

Edit: Should I wait until it's NOT 100?F outside before I try this?

You cannot reasonably expect your car to fully charge that battery up to 100% (this is important) unless you plan on driving for like 28hours straight. I know this because the battery in my sister's Volvo was at 11.8V

What's the output rating for the Volvo's alternator? Maybe I've always had high-output alternators but I've never had a battery fail to charge fully after a reasonable time with the engine running. Edit: Well, I can't say that I've measured to the precision that you did, so maybe they weren't charged fully after a single drive, but even after a short drive it's above 12v, starts the engine easily, and never runs down again until I leave the headlights on again.

Originally Posted by add|ct

I may just buy 1Q of battery acid

...and that's another thing I've considered, but I don't know where to buy it.

[imzjustplayin]

Originally Posted by theholycow

I didn't know it was even possible to buy dumb chargers anymore...,I've been wanting a dumb charger for a while because my damned smart chargers refuse to charge batteries that I think can still be revived.

Well I have a neighbor who was having issues charging is batteries that were at 0V and he had a schumacher "trickle charger" (4amps) that had to have been at least 40 years old. The difference with his and my smart charger is that mine has an actual LCD that gives error codes when it's charging while his simply has a dial. If you don't have a digital display, then you can be guaranteed you don't have a smart charger. I guess it would appear that most chargers for the sake of safety won't charge a battery with 0V.

Originally Posted by theholycow

I considered trying what you suggest with hooking up another battery but I was afraid it could destroy the other battery. Since it worked for you I may give it a try. I have a few batteries that may be revived by it.

Well if you're paranoid (I know I was!) just monitor the charging of the batteries to make sure nothing is happening. What I found which is a little weird is that if you have a 100% charged battery and a fully discharged battery, when you charge them while hooked up in parallel, not only will the discharged battery charge first but it will actually drain the charged battery! Once the batteries were past a certain threshold, I then charge them individually until they're full. Putting the batteries in parallel is mostly for getting these batteries past that low voltage threshold.

Originally Posted by theholycow

Edit: Should I wait until it's NOT 100?F outside before I try this?

If you truly have a smart charger (I don't know if you do) then it will detect the ambient temperature as it's charging. One of the reasons not to charge a battery that was recently used is because it could have been heated up by the engine bay, raising the temperature higher than ambient and since the charger only knows ambient, it can overcharge it.

Originally Posted by theholycow

What's the output rating for the Volvo's alternator? Maybe I've always had high-output alternators but I've never had a battery fail to charge fully after a reasonable time with the engine running. Edit: Well, I can't say that I've measured to the precision that you did, so maybe they weren't charged fully after a single drive, but even after a short drive it's above 12v, starts the engine easily, and never runs down again until I leave the headlights on again.

Yeah a battery that is at 12v and starts the engine easily isn't necessarily charged at all. Most car batteries should be able to crank the engine as low as 10.5V yet 11.8V is considered a "fully discharged" battery. Also if you apply heat to the battery, the battery's voltage will go up so it will appear to be charged when it really isn't at all.


Diehard batteries aren't necessarily bad but a lot of chargers I've seen are not smart chargers. If you can, just bring up a link to a charger and I'll let you guys know if it's a smart charger.. Pretty much the only way to know if it's a smart charger is that not only does it say it but it says something about "stepped charging" and "microprocessor controlled".

[theholycow]

Originally Posted by *************

If you don't have a digital display, then you can be guaranteed you don't have a smart charger.

These seem to be in most stores around here:
http://www.walmart.com/ip/Schumacher...arger/13005743
http://www.walmart.com/ip/Schumacher...arger/13005742

Based on those, I wouldn't look for a digital display to determine if a charger is smart or dumb...neither has a digital display but both are definitely smart chargers.

when you charge them while hooked up in parallel, not only will the discharged battery charge first but it will actually drain the charged battery!

Yup, I knew that; I thought the excessive rate at which it would discharge the good battery was a problem.

Yeah a battery that is at 12v and starts the engine easily isn't necessarily charged at all. Most car batteries should be able to crank the engine as low as 10.5V yet 11.8V is considered a "fully discharged" battery. Also if you apply heat to the battery, the battery's voltage will go up so it will appear to be charged when it really isn't at all.

Ok, I'll buy that.

I guess it doesn't really matter as long as the battery starts the vehicle in cold weather for years afterwards.

When one of my batteries discharges to the point where it won't start a vehicle and I jump-start it, either of two things will happen:
1. I idle or drive for a few minutes and then never have a problem with the battery. It reads well above 12v and starts fine on the coldest days. I have to believe that my vehicle, on an average drive, charges it more than it discharges it and eventually completely charges it.
2. It never charges enough to start the vehicle. It is immediately dead.

[imzjustplayin]

Originally Posted by theholycow

Ok, I'll buy that.

I guess it doesn't really matter as long as the battery starts the vehicle in cold weather for years afterwards.

When one of my batteries discharges to the point where it won't start a vehicle and I jump-start it, either of two things will happen:
1. I idle or drive for a few minutes and then never have a problem with the battery. It reads well above 12v and starts fine on the coldest days. I have to believe that my vehicle, on an average drive, charges it more than it discharges it and eventually completely charges it.
2. It never charges enough to start the vehicle. It is immediately dead.

It's really a bad idea to treat batteries that way because driving around on a fully discharged battery, while it still works will allow sulfation to occur which will diminish the capacity of the battery. A fully charged battery is suppose to be at 12.65V and a fully discharged is around 11.65-11.9V. To put things in perspective, it may take 3 hours to take a battery at 0V all the way up to 11V when charging at 2 amps but it will take 28 hours to take a battery at 11.8V to 12.65v/highest state of charge it will accept. This is because the majority of the capacity of the battery is in the 11.65-12.65v range. Running a battery below 11.8v puts a LOT of stress on the battery. Also if you discharge a battery low enough, the polarity can reverse on some of the cells inside of the battery which can be problematic unless you can get them to flip back to the way they should be.

Also some car's electronics don't take kindly to running on a discharged battery as my mom's LS430 started to act up when the battery was at 11.8V yet the car would crank just fine. The electronics in cars these days has a tendency to discharge batteries very quickly if the car goes more than a day at a time without being driven on the highway. I know it sounds hard to believe but if someone goes to work on the highway 5 days a week and doesn't drive on the weekends, then, over the course of a year, there will be 104 days where the battery isn't being charged.

Just remember this fact: Car alternators are not battery chargers, they're battery maintainers. There is a reason why your alternator "kicks it up a notch" when you run the rear defroster or run a several hundred watt stereo but when you turn those things off, so does the rate at which it charges. This problem with battery charging wasn't nearly as much of a problem in the 70s with carbureted engines and no electronics but IS a problem with cars that have Fuel injection and even worse with those that have alarm systems and other electronic gadgetry sapping energy from the batteries. More proof that those things drain your battery quickly, on my Civic I charged the battery to full then a month later I checked on the battery and it was down to 11.6V. I charged the battery up again but it does remind me how unless you drive your car every day, it's very easy for it to lose charge. I'm going to get a solar battery maintainer so that I don't have to worry about a dead battery in the future. Pretty much every car I've come across that isn't driven every day on the highway has some level of discharge, some are 75% charged, 50% charged or 25% charged.. But then those vehicles that are driven as often as every two weeks, their voltage is around 11.8V.

On a hot day, like 100F, a fully charged 12v lead acid battery without ANYTHING attached can discharge 20% in about a month's time.

[GasSavers_JoeBob]

Originally Posted by theholycow

<snip>

When one of my batteries discharges to the point where it won't start a vehicle and I jump-start it, either of two things will happen:
1. I idle or drive for a few minutes and then never have a problem with the battery. It reads well above 12v and starts fine on the coldest days. I have to believe that my vehicle, on an average drive, charges it more than it discharges it and eventually completely charges it.
2. It never charges enough to start the vehicle. It is immediately dead.

That pretty much mirrors my experience over the past, oh, almost 40 years. Any car I've had with an alternator has had the capacity to charge a battery in good repair within a very few miles of driving.

When I was a kiddie-poo, I had a couple cars with GENERATORS. A typical generator put out about 20 amps or so...barely enough to run the car, the heater blower, the headlights, wipers and light the tubes in the radio. Even then, if the heater was on, the "GEN/FAN" light would glow softly (this was a Corvair). It would easily take a 40-50 mile round trip to fully charge a battery with that car. The smallest alternator I've had on any car was twice the capacity of those generators, and my '80s cars had 100 amp alternators. Modern ones are probably even more. They should have no problem charging a battery pretty quickly.

[imzjustplayin]

Originally Posted by JoeBob

That pretty much mirrors my experience over the past, oh, almost 40 years. Any car I've had with an alternator has had the capacity to charge a battery in good repair within a very few miles of driving.

When I was a kiddie-poo, I had a couple cars with GENERATORS. A typical generator put out about 20 amps or so...barely enough to run the car, the heater blower, the headlights, wipers and light the tubes in the radio. Even then, if the heater was on, the "GEN/FAN" light would glow softly (this was a Corvair). It would easily take a 40-50 mile round trip to fully charge a battery with that car. The smallest alternator I've had on any car was twice the capacity of those generators, and my '80s cars had 100 amp alternators. Modern ones are probably even more. They should have no problem charging a battery pretty quickly.

What you seem to not be aware of is that despite the "capacity" of these alternators, they're not always running at capacity. See the car's ECU and the load sensor in the alternator is what determines the rate in which the alternator outputs. In fact, one of the features of the Civic VX is that it has a less aggressive alternator output where it won't run the alternator all that much in city driving and will be more aggressive when DFCO. So it's very plausible that some auto manufacturers go on the edge and try to eek out as much fuel economy as possible for CAFE regulations by having a very non aggressive charging scheme. So while the car will work fine, the batteries will have to be replaced more often and since nobody is none the wiser, it just goes on.

How you drive is also very important since if you do lots of city driving and turn the engine off and on a lot, it's not a surprise that the battery will be more discharged than charged. Most people have found a 10% fuel economy improvement by removing the alternator belt so with this in mind, it's no surprise this is one area an auto manufacturer will look at in order to improve fuel economy.

[GasSavers_JoeBob]

Originally Posted by *************

<snip>So it's very plausible that some auto manufacturers go on the edge and try to eek out as much fuel economy as possible for CAFE regulations by having a very non aggressive charging scheme. So while the car will work fine, the batteries will have to be replaced more often and since nobody is none the wiser, it just goes on.

<snip>

Naturally, the alternator will put out as much current as is required by the car's electrical system. During the day time, on a 72 degree day, with a fully charged battery, it will be putting out just enough to keep the car running. After a jump start, on a 110 degree (or 20 below) evening, it'll be putting out quite a bit more. The voltage regulator (or ECU) will adjust the output as appropriate.

How often do batteries need to be replaced in modern cars? My perception has been that batteries last longer nowadays than in the before time. Seems that back in the '70s, if I got two years out of a battery, I was doing good. Since the '90s, I've had cars sometimes 6-7 years, and never replaced the battery.

[imzjustplayin]

Originally Posted by JoeBob

Naturally, the alternator will put out as much current as is required by the car's electrical system. During the day time, on a 72 degree day, with a fully charged battery, it will be putting out just enough to keep the car running. After a jump start, on a 110 degree (or 20 below) evening, it'll be putting out quite a bit more. The voltage regulator (or ECU) will adjust the output as appropriate.

How often do batteries need to be replaced in modern cars? My perception has been that batteries last longer nowadays than in the before time. Seems that back in the '70s, if I got two years out of a battery, I was doing good. Since the '90s, I've had cars sometimes 6-7 years, and never replaced the battery.

Well considering that I've had to replace batteries in some newer cars after only 4 years due to the electronics being finicky (this is before I used a battery charger), I'd say you're wrong. The cars that had their batteries last the longest are usually the older ones in my experience. It's possible that the batteries in your cars were exposed to high temperatures and high temperatures + charging = dead battery. This is one of the reasons to keep batteries in the trunk instead of the engine bay. If I had only known that a good battery charger can restore a good portion of a battery's life, I might not have replaced that 8 year old battery in my LS400.

I think we're dealing with a multitude of problems and don't even realize it.

[bobc455]

Originally Posted by *************

What you seem to not be aware of is that despite the "capacity" of these alternators, they're not always running at capacity.

I had a car that always ran at capacity. The extra amps fell out the back of the alternator and made a puddle on the floor.

[GasSavers_JoeBob]

Originally Posted by bobc455

I had a car that always ran at capacity. The extra amps fell out the back of the alternator and made a puddle on the floor.

That's no problem...scoop up those amps, take them to the swap meet on Sunday, and sell them to the kids who have those big sub-woofers!