45

It is the difference between the verb and the noun. You are right, the verb throttle means to restrict - to slow down flow, therefore to fully throttle is to stop the engine. However, the noun throttle refers to the mechanism. Thus setting a full throttle means that the mechanism is set to fully open - unrestricted. Don't ever expect the English language to ...


24

That is your actual bumper The bumper you have off is just a cover for your real bumper which is what you are describing. That bumper, the real one, is tied to your frame and is actually absorbing the energy from impact where the facade is just existing as a cover due to the ugliness of the actual bumper.


18

After a little digging, I have found pretty much what Ben said in the comments above: A moonroof is a sunroof, but a sunroof is not a moonroof. The difference is not in how the mechanism moves, but what it holds. A sunroof consists of a metal panel that can either tilt up, and/or slide back into or above the roof of the car. A moonroof, on the other hand, ...


18

Valve float means the valve doesn't fully close at the proper time, because the return mechanism (usually a coil spring) isn't strong enough to close it. This usually happens at high RPM. It can damage an interference engine if the valves make contact with the top of the piston. This can bend the valve stem, or chip the edge of the valve. In addition, ...


16

Valves can bend, break and/or burn. If the valves don't provide a complete seal, for whatever reason, the hot gases are forced past the valve which eat away or burn away the edge of the valve due to concentration of heat and pressure. Causes that I can think of - Anything that causes incorrect valve seal Cooling issues (improper cylinder head cooling)? ...


16

Motivation Fuel trims are a neat mechanism employed by auto manufacturers to reduce the sensitivity of fuel management to operational deviations. Modern-day fuel-injection systems rely on inputs from many sensors that expect several engine sub-systems to be in tip-top condition. With use and age, many of these sub-systems will experience some degree of ...


14

To go down hill By setting L (or 1 or 2), the gear will stay low and you will be able to use engine brake, instead of using brakes all the way down the hill and suffering from fading. The transmission will not necessarily pick a lower gear when going downhill, although they will pick a low gear if you are going uphill. Never brake the car for an extended ...


11

I do not know the etymology of these words or the history of their use in the context of air-fuel ratios, although their dictionary definitions (lean [adj.], rich, too bad I don't have an OED subscription) and usage in other contexts does parallel their usage here. I did some cursory research but gave up, the folks on the English site may be able to help ...


10

Most valves are opened by the cam lobes, and closed by springs. However, it takes time for the spring to 'unwind' and push the valve back. If the engine is going fast enough, this time is longer than the time it takes for the cam lobe to rotate from 'fully open' to 'fully closed', so the valve doesn't follow the cam - a gap appears momentarily. This means ...


9

This part is generally called the impact bar, or sometimes reinforcement bar or bumper reinforcer, and, along with the (often styrofoam, sometimes plastic, missing or hidden in your picture) absorber pad, serves the actual safety purpose of a modern bumper. The plastic piece is called the bumper cover. The absorber pad is crushed to absorb energy in a crash,...


9

@Zaid Thanks for contributing this knowledge! I just want to post my own description because it took me more than one read-through to understand your answer. My understanding of the situation: Ford had invested in manufacturing the original 4.0 block several years ago. There was no reason to design and invest in a new block. There was already a hole in ...


9

Two additional uses alongside engine braking controlling downhill descents: Low gear, high revs uphill on loose ground like sand If you need to go up a steep hill on loose terrain like a sandy dirty track, dune or fine gravel, you need to build up momentum before hitting the incline and you need to put your foot down and get high revs for the speed you're ...


9

Brake Horse Power at 6600 RPM. BHP is measured at the crankshaft. This post gives a nice description of how the BHP is calculated.


9

I'd say the following, which seem fairly universal: Nothing - the worst option, you turn the key and nothing happens at all - either the battery is flat, the immobiliser is misbehaving, or the starter solenoid isn't getting any signal/power. Clicking - the starter is engaging, or trying to, but it's not turning the engine. It might be that it's failing to ...


8

A burnt valve can happen for one of many reasons, but the underlying issue is, the valve is not sealing correctly and allows hot engine gases during the combustion phase to leak past the seal which is formed by the valve and seat. When the seal is lost, the hot exhaust gases escape past the valve (can happen to either the intake or the exhaust valve, but is ...


8

Much of the information in this answer is adapted from this excellent forum post In the generic sense A jackshaft refers to an intermediate shaft that transmits rotation/power from one shaft to another. Per Wikipedia: A jackshaft, also called a countershaft, is a common mechanical design component used to transfer or synchronize rotational force in a ...


8

Newton meters of torque at 4600 RPM. NM is the metric way of measuring torque similar to Foot Pounds being the SAE way. The engine torque output changes with the RPM because the engine breaths differently over the RPM range.


8

German here. The word "erneuert" always means that something has been replaced. The only remarkable exception is a "runderneuerter Reifen" i.e. a retreaded tire, though... even here something has been replaced. The term "überholt" literally means "overhauled" or "refurbished" Further more, mechanics here mostly just replace parts instead of fixing them, ...


7

A lean air/fuel mixture is when there is more air than required to burn the fuel. A rich mixture is when there is too little air for the given quantity of fuel. The ideal mixture, where there is exactly enough air to burn the fuel is known as the stoichiometric mixture and is about 15:1 for gasoline. That means 15 parts air to 1 part fuel. You can have a ...


7

The rear of an automotive engine is the side the power is taken off of. The side where the clutch or torque converter attach. The other sides are in relation to the rear: the side opposite the rear is the front, and the left side of the engine is the side on your left as you look at the engine from the rear, and likewise the right. I would guess that the "...


7

The only time I've ever felt the need to use anything other than 'D' in an automatic is when towing or climbing a steep grade. That's not to say I don't play around like it's a stick shift sometimes, but as you said, it's not necessary. The other day, I had to pull a damaged car (one wheel was locked up) across an apt complex. I put the tow car in 1 in ...


7

Your explanation of the application in the Ford motor is spot on. To answer the original question of "what is a jackshaft?" in a broader context: a jackshaft is simply a shaft that transfers rotational movement from one path to another. Basically, it's a spacer between chain and/or belt drive circuits. Here's a few pictures that illustrate the concept.


6

This is a typical torque diagram (this appears to be for an LS1 engine), this is in lb-ft instead of Nm but the idea is the same. The peak torque seem to be around 350lb-ft @ 4200 RPM. The peak power ~340hp @ 5500 RPM. The hp (power) is a function of the torque and the revs per minute and a constant (which comes from pi, and minutes to second etc). power[hp]...


6

The force required for the driver to turn the steering wheel would be a torque measured in foot-pounds (or Newton-meters). Extra Credit: The actual force required for the rack in a rack and pinion style steering system to push/pull the tie-rods to turn the wheels would be a simple load measured in pounds or kilograms. The actual load the tires experience ...


6

What is a CV Axle? CV stands for Constant Velocity. It's a type of axle which is used on front wheeled drive vehicles which allows power to still be transmitted to the front tires even while wheel is turned. It is called "constant velocity" due to the way it's designed. No matter which way the outer section is turned, it will remain at the same speed as the ...


5

While the others has stated why you might want to use one of the lower gears, they aren't explaining what happens when you actually use the lower gears. On most vehicles with automatic transmissions, when you put the vehicle into "2", the transmission goes into second gear. You don't start in first gear, then shift up to second, it starts in 2nd gear. This ...


4

In UK usage, an opening glass panel over the front seats is a sunroof whether it tilts, slides or both. A second such opening over the back seats was sometimes called a moonroof (this was common when the Espace first came out, so late 80s).


4

tl;dr In general, short block = block + rotating assembly long block = short block + heads When talking short or long block, you are suggesting the completeness of the engine. Basically, a short block will consist of the following: Engine block Main caps Rotating assembly Crankshaft Connecting Rods Pistons Rings Bearings (both rod and main) Freeze ...


4

ANSWER No Orbital motor and hydraulic motor are not synonymous terms. A hydraulic motor is essentially a hydraulic pump in reverse. It has one or more pistons that move in a cylinder, with valves and timing, rather like an internal combustion engine powered by compressed air. By comparison, here's an orbital motor. Main advantages are that the "motor" ...


4

Both are just called either the gear lever or shift lever (in the UK anyway) Auto or manual then just refers to the transmission type.


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