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48

It is a turbo timer. The theory is that an engine with hot turbocharger shouldn't be immediately turned off. The turbocharger may be damaged because there will be no oil flow. The timer ensures that the turbocharger has managed to cool down enough by idling. Now, do you actually need the turbo timer? Probably not. The turbocharger is hot only after hard ...


35

Car batteries are not only rechargeable but are constantly being recharged by the alternator. Simply starting the car takes a lot of power reserves from the battery, then electrical systems such as the headlights, screen heaters, ignition and injection systems all draw on the battery. When the engine is running, the alternator is near constantly providing ...


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.


33

The 15V is not a real reading. It's an artifact of bubbles formed on the plates from overcharging, which have by themselves an anode and a cathode. This creates a false" voltage potential that really isn't there. (Well, technically it's there, but the bubbles are acting as tiny cells in series, but have no actual stored potential. A high impedance DVOM ...


28

This is going to get a bit technical but should still be understandable even if you slept through chemistry classes. When is hydrogen dangerous? Just as with the fuel-air mixture in an engine, hydrogen is combustible only when it's within a range of concentrations. We use what are called the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) ...


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 ...


21

The battery is toast. Save yourself potential serious injury. Buy a new one. If the battery has been dead for eight months...it is pretty much a goner.


21

It's because of a couple things: The battery is very dead and the alternator cannot put out enough power at idle RPMs to run the whole system and charge a battery. This leads to a lack of power which may kill one or more systems most likely the spark "ignition" system since this takes the most power and is necessary to run the car. In Fact you can remove ...


21

I'd just disconnect the negative, personally. I'd also recommend having a look at some of the questions and answers on here about storing vehicles for a long time: Long-term-storage As these may give you other useful advice - for example, jacking it up so you don't get flat spots on the tyres.


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 ...


19

The reason I would connect the positive cable first (in a negatively-earthed car) is that while tightening the positive connector with a spanner (wrench), if I were to touch the body of the car with the spanner at the same time, nothing would happen and I would be OK. However if the negative was already connected to the battery and I shorted the positive to ...


19

Your question is difficult to answer without you knowing the inner workings of an alternator. The basics. If you move a magnetic field near a coil of wire the electrons in the wire get excited and electricity will be made. The amount of electricity made depends on the size of the magnetic field and its speed. The bigger the field and the faster it's moving ...


18

Corrosion on the terminals is due to hydrogen gas being released from the acid in the battery. It mixes with other things in the atmosphere under the hood and produces the corrosion you see on the terminals. Generally, if the corrosion is occurring on the negative terminal, your system is probably undercharging. If on the positive side, it is probably ...


18

Use the jumper battery to start the engine, then disconnect it and leave the engine running (with no current drain such as lights, heater fan, radio, etc). The car should charge its own battery to 80% charge in about two hours (assuming the battery and alternator are in good condition; the battery may be damaged by being uncharged for so long, but I've never ...


18

I can't give you numbers or calculations without some work, but I can tell you than energy is never free. Cars have an A/C compressor that is mechanically driven by the engine because this is the easiest way to get the job done in a typical consumer car. An A/C compressor actually takes a huge amount of energy to operate. In fact a central A/C unit for a ...


18

These are some general guidelines when working with electricity on vehicles: Always remove any jewelry, to include rings, necklaces, watches, etc. If one of these items should come in contact between a hot and ground, it will instantly go hot (if there's enough amperage flow) and will burn into your skin requiring surgery to remove. These are a "no matter ...


18

To answer your question, it will not cause any issues as long as the cables are connected correctly. If both donor cars are connected in parallel (negative to negative/positive to positive) to the recipient vehicle, there should be no issue.


18

The cost has been addressed, but there's an underlying question: is the battery dead (i.e. it cannot hold enough charge anymore to start the car), or has it just been discharged? If it's just been discharged (e.g. by leaving the headlights on while the car's parked), charging the battery is the best option. If the battery is dead, you'll have to replace it....


17

With the description you give, I'd say you connected them backwards with about a 99%+ assurance. Large amounts of sparks followed by heat are both VERY BAD SIGNS (as you soon figured out) and almost always mean you have the jumpers on backwards. Never trust what the covers on the battery says. Check what the battery says to be sure. If there is no way to see ...


17

When you jump start a car, you are always putting the cars in a parallel circuit. Here's an illustration of parallel vs. series: Source Think of the bigger car's battery as the one on the left and the smaller car's battery as the one on the right. When you connect jumper cables, you connect the positive terminal on the bigger car to the positive terminal ...


16

This step is a carryover from days gone by and is not needed in modern vehicles. Batteries from 50 or 60+ years ago were not as powerful or reliable as modern ones. Older batteries had difficulty handling the load of the starter motor alone. Engines cranked longer before starting and were cranking large displacement engines. Any added load from wiper, radio ...


15

The biggest thing to look at for me is the gauge of the wire. The reason I bring this up is, the higher the gauge (numerically) the thinner the wire. Thinner wire will require your jump-start procedure to take more time, as it takes a while to charge the battery before you'll have enough juice to get it running. Thinner wire cannot pass enough amperage to ...


15

When disconnecting a clamp from a car battery, there is a danger of creating a short circuit with the tools that are in contact with the battery terminal. So a tool in contact with the positive terminal can cause a short circuit if it touches any piece of grounded metal. Starting with the negative terminal removes this danger; now you only need to ensure ...


15

Sure you could put a bigger battery in .What may happen is that the total proposed draw is too much for the dynamo and it will go flat.Even if it does not go flat because your appliance usage patterns are intermittent you will get a lower battery life because of the constant cycling .If dealing with the charging system is too hard or too expensive then ...


14

You should be able to sneak a clamp on to the positive terminal, and there's an auxiliary negative (ground) terminal lug nut to clamp onto right in front of the coolant fill tube and power steering fluid reservoir. Otherwise if you really want more room, you need to remove the intake tube (nothing to do with exhaust) by disconnecting it at the rubber ...


14

Most modern diesel engines (ie: engines after mid-80s) require some electricity to run because they are electronically controlled. This is due to computers controlling the fuel charge and monitoring of the engine itself. Without this, the diesel engine has no control. They also require electricity to power the primary fuel pump, to move the fuel from the ...


14

I don't know the actual justification, but to me it makes sense to always attach positive first because it is easy to accidentally touch the lead to something else while installing. If the negative lead were already attached, then touching the positive lead to just about anything on the car that is metal would short out the battery.


14

tl dr: Corrosion (once cleaned) is not a huge issue. It is just typical corrosion on the battery terminal. See this image: (NOTE: This is a 6V battery, but the same principles apply.) The blueish color you see is hydrated copper sulfate. When acid vapors escape from the battery, it can cause a reaction with any copper which may be in the terminal. The ...


14

Yes, as everyone is stating, a spark igniting hydrogen gas could cause an explosion, causing injury from small parts, sulfuric acid or both. Very nasty. Hydrogen gas is a byproduct of electrical energy created from a chemical reaction of lead plates submerged into the acid and water. Sparks can happen internally, too. Like when the lead plates warp from ...


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