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35

I think your guess will be correct. The clamp has probably been over-tightened in the past, has stretched and is no longer giving a good tight connection. The copper will have been added to act as a shim to make a tight connection.


28

The main reason those would be sticking out of your battery post/terminal is because the terminal clamp has become too stretched. Someone put the copper wire in there to take up the slack of the clamp. Without them you'd lose connection and the battery would not provide the power to get the car started as well as the system having the ability to charge the ...


24

You are right in the thinking of using less gas and that's exactly what the purpose was to have the start/stop feature. The main goal of doing it (at least here in the States) is for zero fuel consumption/zero emissions while the engine is stopped. This provides for better overall fuel consumption numbers to meet what the EPA has mandated for companies to ...


22

A rounded bolt is not a reason to junk a car. The numbers you're quoting sound fine for an alternator; if it was below 12V, I'd be worried. If you're still concerned, take the car to a spares store and ask them to check the battery and alternator. When it does come time to change the alternator, getting the bolt off would not take a lot of extra time; there ...


20

The oil problem You can run any engine speed you want as long as you keep the oil pressure up. Because of the impossibility of getting a roller bearing down a crankshaft, engine bearings are "plain bearings" with polished steel floating above babbitt (a soft metal). The oil pressure makes the bearings "float", so the dynamic forces of pistons being ...


8

The engine needs a minimum rpm to idle smoothly - a v8 can idle smoothly about 500to 600rpm but a 1 litre 3 cylinder needs around 700 to 900rpm... It is not the companies that really decided to do the start/stop, if you do some research the various governments have implemented legislation over the years that required drivers to turn off the engine when ...


7

You're right that 10 amperes is faster, by a factor of 5x. Lead-acid batteries are charged in 3 stages, first by constant current (with voltage limit), then by constant voltage (with tapering current), then in the end during float charge the voltage is reduced to a float charge voltage level. The 2 ampere and 10 ampere options allow charging different ...


7

There are several possibilities: The bike's battery is bad. This is by far the least likely cause, as the previous battery behaved exactly the same way. The chances of having two batteries fail sequentially in the same manner is very low. The battery is not being charged when the motor's running. If there's something awry with the charging circuit or its ...


7

All batteries last about the same amount of time, given the same climate and average use. I'm betting the dealership uses a large battery warranty to lure you in to other services, like a "loss leader". It's also common with free oil changes when you buy a car at a dealership. They lose money on the oil change but plan on you buying other stuff at a premium.


6

I have seen somebody spot-weld a short bolt to the rounded nut they are having trouble removing. It's cheap and quick if the equipment is on hand.


6

If you do a search for a 78DT battery as on the label on your battery, you will find that it is a dual terminal battery. It has 4 poles, but one of the top ones in your photo has a cap on it. If the cables on your vehicle will reach to the top poles of the existing battery, then you should be able to replace it with a ‘normal’ 2 pole battery with suitable ...


6

They may make 100-months guaranteed batteries with higher real capacity than 60-months ones. Higher capacity means that harmful events like overcurrent or deep discharge are less likely to happen, and that a battery still works fine after losing some of its original capacity, because the remaining capacity is still enough to reliably start the car. I would ...


6

You may just have a bad connection on the battery posts. This would account for the sudden loss of power and also explain why everything powered up once the jump leads were added. Try disconnecting the battery connections and cleaning the connectors and battery post with some sand paper or wire wool, then reconnect. The reason why the car would not start ...


5

I'm not entirely sure that this question fits the primary purpose of this group BUT I have to say that I've long wondered why electric car manufacturers don't standardise on a battery format and devise some sort of unattended method of battery replacement. I thought something that you drive the car onto and then the battery pack is ejected from underneath ...


5

TL;DR: This idea is old, like OLD (1890s), but so far nobody has been able to set it up in a financially viable way. History The steam car, the internal combustion engine automobile, and the electric car emerged as the main competing technologies in the late 1890s until the 1920s. The concept of exchangeable battery service was first proposed as early ...


5

If the clamp is no longer getting tight enough, that could mean the metal is stretched and possibly weak. A dealership would want to replace the whole ground cable with a new, molded on clamp. If there is any slack in the cable, you can buy a replacement clamp and put that on the wire. One way or another, new clamp is the "proper" fix. In the mean time, ...


5

Replace it, with something like this:


5

I suspect it would be a good plan to check your terminal connections and other points associated with the power to the starter or solenoid. A poor connection in this circuit would present the characteristics you describe for a slow turnover and failure. It's possible that during your attempts, the bad connection(s) heated up due to the high current and high ...


5

From physical point of view, lowering the RPM means that you need to store the energy required to keep the engine running (and overcome friction) with a smaller angular speed. And the kinetic energy is proportional to speed squared. If you want to go from 600 RPM to 100 RPM, you will have (among other things) to make the flywheel 36 times heavier. Of course,...


5

A battery should be able to run the flashers for several hours and still start the car. There should be a sticker on your battery which tells the month and year it was manufactured. The sticker will either be M/YY indicating the month and year, or a code such as D6, where D is the fourth month of the year (sequentially mapped months A-L), and 6 is short for ...


5

In a word: Absolutely The lack of material means a lack of electron flow. You won't get the proper charge of the battery, the right amount of power out of it come starting time, nor the full buffering effect a battery provides to the electrical system. It is a lose/lose/lose situation here. Replace it. It doesn't have to be exactly the same type. In fact, I'...


5

The grease is there to prevent corrosion on the battery terminals, when you put the connector on and tighten it down the grease gets squeezed out and what's left prevents corrosion where there's no metal to metal contact. If your battery came greased then there's no reason to clean the terminals unless the grease got rubbed off and the terminals corroded. If ...


4

The battery is located in the trunk next to the spare. There is a positive battery terminal in the engine compartment located next to the fuse box. Maybe this is what you are referring to as a smaller second battery? It's just a convenient place to access the positive battery connection from the engine compartment.


4

Given how complicated this seems from both posts, I would suggest that you fit a known good battery and run the complete set of tests on the charging system. I would include the tests for voltage drop across all the cables just to make sure. These tests are usually given in the workshop manual, but basically involve having all heavy loads on (lights, heater,...


4

Car companies focus on stop/start of the engine simply because There's a minimum RPM the engine can run at. You can sort of extend it using dual inlet/exhaust variable valve timing, but there are limits to that. If the engine is running, it's consuming some amount of fuel always. Also, some companies go bit further than stop/start. They stop the engine ...


4

TLDR: use 2A when unattended. An ideal battery charger does 3-stage charging based on the battery voltage - to quickly charge in the midrange, taper the charge near full, and then trickle at the right rate once full. This requires a fair amount of intelligence in the charger. Overcharging damages the battery. (Lots of things damage lead-acid batteries,...


4

Why copper? Because it is soft without being too plastic and easy to obtain. It is also highly conductive both thermally and electrically. Why do it? The terminal no longer clamps the post. The post is too small or the clamp is too large. This creates a sleeve. The thread on that bolt may also be stripped or seized. It is very commonly done to just hammer ...


4

Sounds like your battery terminal connectors are stretched to the point that they are loose even when the bolt is fully tightened. Best fix would be to replace them with new connectors. Alternatively you could add a thin shim of metal between the post and the connector. Since the metal lead (battery post) has a high thermal expansion coefficient, my guess ...


4

The test you are doing is not valid and shows you nothing really. For a start, you have not got it wired in parallel, you have got it wired in series. You would usually wire a voltmeter in parallel to measure voltage. You are therefore measuring the battery voltage with some voltage dropped across whatever is turned on in the car at that moment. In a ...


4

I've heard that AGM is "the best" and that LiPo is "even better" but "much more expensive". However, a standard maintenance-free battery is 30-50€, a LiFePo4 is 40-90€, AGM is >150€. I haven't seen standard LiPo in this size for sale, not through the usual suspects. If by LiPo you mean LiFePO4, then yes, in general lithium ion batteries, when properly used, ...


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