Force alternator to ALWAYS charge?
 

Hiya y'all!

I EOC (engine off coast) SO much it's hard to keep my battery fully charged.

Is there a way to manually override the voltage regulator to force the alternator to ALwAYS charge the battery. For long freeway passages, I'd like to be able to throw a switch to put the alternator into it's normal charging state.

Thanks,
Doug :)

What about plugging a battery charging pack on overnight, however many times a week or month this is required?

Get yourself a Solar panel Doug, I have one on the Honda, connects directly to the battery terminals and keeps the battery topped up, the panel is small and just sits on the dash. Worth a shot?

The problem is, if your battery is even the slightest bit low, it will charge automatically when you restart the engine. You probably either need a larger battery and possibly a higher rated alternator.

I'll second those replies.
If the battery is low, the system should be charging it automatically.

I try to top off my battery once in awhile with a charger. I like the idea of the solar battery tender, but I make regular use of windshield shades in the warmer months, and you have take airbag placement into account when placing it.

Before upgrading the battery and/or alternator. I'd get the current battery checked. EOCing will age it quicker, and it just might be dying.

How old is the battery? Lots of EOC will drain the battery. Best solution is a new-bigger battery, combined with charging it overnight, if practical.

I'd be with Paul on the solar panel option, depending on where you are, there should be 8-10 hours of daylight to trickle some extra power into the battery.

Oliver.

Gee. I didn't know that EOC was known to be hard on car batteries. Thanks for that factoid. R.I.D.E! Hmmm. Never used that word before. What's the difference between a "fact" and a "factoid"?.

Because the battery was only charging up to 12.4 volts, I thought it was a battery problem. This September the battery will be 2 years old.

So, I removed the battery and, over a week, I put a battery disulfator on it while intermittently charging it. Got it to reliably hold 12.6 volts after a resting state of many hours.

After driving around with the fully charged battery it's down to 12.4 volts, AGAIN!

I confirmed excellent continuity between the alternator ground, block, and chassis.

That led me to suspect the alternator or it's internal voltage regulator. But the alternator does put out 14.1 charging volts.

Now, knowing EOC is hard on batteries, I suppose OliverGT's suggestion of installing a solar charger is the best solution. Does anyone have an alternative idea?

This concern will eventually go away when I trade this 27y/o Civic for a USED Tesla 3. ;)

Ok. Here's what I've engineered. Instead of mounting an unsightly solar panel on my car's roof, I will have a pole dancer.

If my calculations are correct, which I can't be too sure, because my hand was trembling with excitement as I was doing the arithmetic, a decent pole dancer should be able to put out more than enough energy. I figure the energy output can be regulated by the choice of music.

We'd all like to see this Doug, please post appropriate pics and vids to help us appreciate your idea.

As i speak Polish, and am known to dance (think '90s raver with the stamina long gone), i appreciate your train of thought - good luck.
You'll have no problems attracting foxy exotic pole dancers to your mid '90s Civic - i'm sure i saw on Honda Karma that they are renowned babe magnets.

SURE! Happy to accommodate, Paul. See attachment. This is merely a rough, proof-of-concept.

And, Ben, YOU were right about my 1989 Civic being a babe magnet. A McClaren owner could not expect to give a girl of this breadth a ride.

Thoughts?

As she gyrates on the roof, my car is most unstable in straight line driving.

On the other hand, if she leans to the opposite side, while taking turns at high speeds, my 27y/o Civic handles like that of a Formula One car.

That's the slimmest American I've seen for a long time! :eek: ;)

hahahaha TOUCHE, Paul! No defense. I lay myself at the mercy of the court.

Now i do like 'em big - but them curves need to be proportion. I cant give her more than a 4 out of 10...
On the plus side, you'll be able to sell the excess energy in your car battery back to the electricity company.

A comedian said, "Trying to get a fat girl drunk is like trying to fill the gas tank of an RV (campervan)."

Okay. Here's my solution. You'll need to connect the dots, so put down the pint, Paul, and pay attention. That means you, too, Ben.

To monitor my battery voltage, I've been using a voltage reader, which plugs into my cigarette lighter outlet. See picture.

It's cheap. My REAL voltmeter reports it's VERY inaccurate. To make up for that I simply add 0.4 to the reading.

I recently noticed if I quickly turn on/off my headlights, the alternator will start putting out 14.3 volts.

Oddly, if my engine RPM changes, the charging stops. For example, while idling at a stoplight and charging the battery with this trick as I accelerate away the charging stops.

Same thing happens when on the move. I can be driving along, turn on/off my headlights, but if I speed up the charging stops.

Turning on/off my headlights tricks the voltage regulator to begin charging the battery.

Because I EOC so much on city streets, the engine is never running long enough to be practical to charge the battery in this manner.

However, on my return leg home, I can deliberately let the engine idle at a few red lights and induce a battery charge before putting the car away for the day.

Thoughts?

For EOC do you actually turn the key, or i've heard people have "kill" switches fitted on the dash or gear stick...?

I key off the car, Ben.

I've heard of kill switches, too, but don't know the pros/cons of either way.

Is there any danger of losing brakes and power steering in an emergency?
I found just coasting in neutral, but engine on, too much of an out of control uncomfortable feeling!
Have you compared EOC and driving without turning it off during coasting?
I was lead to believe with older cars it often used more fuel restarting the engine than leaving it running unless it was for long periods.
I occasionally turn the Honda off if first at a stop signal, but it is a faff restarting on the key.
The whole EV at slow speeds is pretty sweet with the Prius. I liked my old stop-start in the Hyundai, but it was hit and miss if it worked.

Someone in an eco modded Geo Metro posted about a great eco marathon result and had a kill switch mounted on their gear lever.
I don't know about difficulty or cost of installation , but it sounded easier than switching the key.

There's plenty of vacuum assist left to keep the brakes working.

No power steering. It's a 1989 Civic!

Having SO much success with EOC (54.9mpg last tank) I have no interest in coasting with the engine on.

Perhaps it's older carburetor cars that use more fuel for restarting. My 1989 Civic was the first year Honda used electronic fuel injection.

I don't mind switching off the key, although I do end up giving passengers a long explanation about what I'm doing and my sister yelled at me for my "being cheap".

Ha ha ha! How does your last tank compare to a tank where you didnt bother turning the engine off?

39.3mpg was the first tank I posted on Fuelly. Big improvement at 54.9 now.

Cant argue with that - i'll even boot hooters chick out the passenger seat for a 16 mpg increase. ..

Okay. Just got done doing 800 mile roundtrip to Los Angeles. On the long freeways legs, I posted some pretty disappointing numbers around 45 to 50mpg, when I was expecting to best my 56mpg record.

A lot of that travel was at night, where, when the headlights are on, the alternator is constantly running.

My original problem was that EOC does NOT allow enough engine running time to properly recharge the battery.

Not realizing that the alternator causes SO much drag on my tiny 1.5ltr engine when it's running I had thought the solution was to trick the alternator into running more often.

In light of my poor MPG Olympic performance, I've decided a solar panel charger is the best way to go.

Now I have to wait ANOTHER 4 years to compete in the next MPG Olympics. :(

The alternator constantly runs and the built in voltage regulator tries to maintain a constant voltage at all times.

Doug I'm not sure the alternator is the issue here, there are millions of small cars, a lot smaller than yours and charging is not an issue. Have you considered all other possibilities?

What happens to power steering/brakes etc. during EOC? Seems like that might not be the safest situation for maximum car control.

Your insurance would be completely void in an accident too, not worth the risk for a few cents of gas in my opinion.

Just a note. Hondas use a dual mode alternator to save fuel. During light loads and steady driving it charges at 12.2 volts to reduce engine load. When the lights come on or battery voltage gets too low it will switch to 14v charging mode.

Here's a good article about it.
https://opensiuc.lib.siu.edu/cgi/view...text=auto_pres