New answers tagged

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Here is something to try. Start the car, then disconnect one of the battery leads. Should stay running, if it does, turn on the lights. IF it dies, it is your alternator. Might have enough strength to keep it running with out too much of a load(without lights, a/c), but not enough with a higher load. That will also weaken the battery. The cheap way to ...


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my first guess would be that there is a problem with your idle air control valve. when you turn on extra loads like headlights or the rear defrost it is the IAC which rev up the engine to compensate for the extra load.


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The spark plug heat range refers to how well the center electrode conducts heat to the head. A hot plug can't conduct the heat very well that is what makes them hot, they can't cool themselves. A cold plug conducts heat well, by moving heat away quickly the spark plug stays cool. The need to control the temperature of the center electrode comes from ...


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You can run into a few problems with over-filling your engine oil. It depends on how much you overfilled your oil pan. A half a quart over is ok. If you put an entire quart or more over, this could be a real problem. When you over-fill to that extent it can cause issues with gaskets being subjected to pressures they were not designed to be subjected to. ...


-1

In most engines the surface of the oil in the oil pan is close to the crankshaft. If the oil is overfilled to the point that the crankshaft hits the oil, it can cause the oil to form foam. This will in turn decrease the efficiency of the oil pump, which will be pumping a mixture of air and oil. This means that parts that depend on the oil pump for ...


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Generally, in the automotive world, there are two different types of dynamometer (or dyno for short) which might be used: chassis dyno; engine dyno. I'll discuss the general procedures for each type of dyno. Every dyno operator has their own procedure and will operate it how they see fit. You have to allow for this mainly because it's their dyno, they paid ...


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Honestly it would be cheaper to buy a new engine rather than rebuild. Your looking at roughly 26.6 hours. This is just labor, this does not include new seals, bearings, gaskets etc... R&R on an engine is 11.6 hours.


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In your other question: What is the effect of the throttle body on the power curve produced by the engine?, I answered the question of what a throttle body (TB) is and it's basic operation. In the answer, I talked generally about how the function of the TB. I point others there so they have a basic knowledge. Back to this question: There are two main ...


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One of the few reasons to change to an aftermarket throttle body is performance. The throttle body is a common bottle neck that may restrict air flow. This restriction comes from one of two places. The engine has had upgrades or some kind that allow it to "breath" better. While the throttle body was not restrictive before the upgrades, now that the engine ...


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What exactly is a throttle body? For a gasoline engine, the throttle body (TB) is the mechanism which controls the flow of air into a fuel injected engine. It is the "front door" if you will. Inside of most TBs you'll find at least one butterfly valve. There will usually be a main rod going through the center of the butterfly valve which allows the ...


1

Actually with modern engines, they can and do come on after startup. I think the reasons are spelled out fairly well in this article on Engine Builder Magazine: The government wanted to reduce the amount of diesel hydrocarbons and nitrogen oxide levels being emitted from diesel engines. Now, this is where the importance of the glow plugs comes in. Not ...


1

Check; 1 - Battery voltage is ok 2 - ignition voltage comes to the spark plugs (remove one of the s.plug caps and hold it close to a metal surface on the engine and ask your friend to crank the engine to see if spark exist) If there is no spark, refer to the car manual (ignition system wiring drawings) to see related fuse/relay/diodes. 3 - pressurized ...


0

I had similar symptoms in my '97 Civic: ran great when cold, tough to start when engine was hot, engine would stall under load (getting going from a stop), but would also have an intermittent rough idle. After replacing several coolant sensors and a fuel filter, I ended up having to replace the distributor cap, rotor, and coil pack to solve the problem. ...


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This particular bottle is knows as a degas bottle. The reason it has a strange shape is two fold. First, the bottle needs to fit somewhere and the shape helps that. Second and more important is that these degas bottles hold pressure. The shape reinforces the bottle so that it does not explode. In cooling systems with degas bottles the coolant does not ...


0

I also experienced the same thing with my jeep. I tried to correct the fault myself by loosened up the idler pulley bolt,turned the adjustment screw clockwise bringing the idler towards the belt it makes the belt tighter. Now no more squealing. It hardly took 5 minutes for me to correct the problem.


2

There are two answers to this question: Theoretically, radiators are completely optional on engines. Air cooled engines have existed for a very long time. The function of the radiator on these engines is replaced by cooling fins to extract the heat and release it into the air, and they also have oil coolers as well to carry out the heat. However, if your ...


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A 'Blower' is another name for a supercharger, particularly 'Roots' type superchargers that use long figure-of-8 shaped vanes to force or 'blow' air into the engine. The only 'specific requirements' are that the engine internals are strong enough to cope with the extra power and the fuel system can provide enough fuel to match the extra air from the blower. ...


1

A costly mistake (that I just made) while rotating engine forward to gain access to the rear sparkplugs: You can end up with your keys locked in the car. Many sites recommend that you put the car into neutral prior to loosening the "dogbone" which lets you rotate the engine forward more easily. In order to put the car into neutral the obvious thing is ...


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One possible cause might be the 16-year old, slightly mechanically stretched timing chain that gets the "right" amount of additional elongation from the warm engine that puts the engine timing and more specifically the ignition timing out. Another component that could lead to problems with the timing chain is a faulty tensioner.


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There are two possible reasons As mentioned by @user5626466. Improper circulation of the coolant in the engine. If you have the habit of using tap water instead of the coolant, the fine holes in the engine case which circulate the coolant to all the engine parts may got clogged and some parts might be rusted which may affect the flow of coolant. This ...


3

If while trying to start the engine without pressing the brake, the engine turns over but does not start, then I would suspect a fault in the brake booster that is letting unmetered air into the vacuum circuit. This would cause a very weak mixture while the throttle is closed during starting, which would cause the problem you are having. When you press the ...


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I would take a guess at a faulty ignition switch. The radio usually comes on with the ignition witch in position 1, but the ignition in position 2. The radio stopped working, then after turning the switch, the ignition stopped working.


3

If your car was running ok, then the alternator was at least providing charge. The fact you couldn't turn it on again after stopping suggests the battery was not holding any charge. So my initial guess would be battery (after eventually deciphering your question I realise you already tried replacing that) I'd suggest you do also look at the alternator as ...


1

A bit of research has taught me that Brake Mean Effective Pressure is the ratio of an engines Torque to it's displacement, whereas the Brake Specific Fuel Consumption is the ratio of fuel consumption to the power produced. In other words, BMEP will tell you how much power you can get from your engine at a given designed displacement, whereas BSFC will tell ...


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This video confirmed what I was thinking. You need three things: Flat tip screwdriver Hammer Channel locks pliers (or ViceGrips) Take your screwdriver and hammer. Place the screwdriver flat along the bottom of the freeze plug. Hit the screwdriver with the hammer until the freeze plug "eye lids" (as the guy called it ... this is where the freeze plug ...


4

Regular valve springs won't cut the mustard in F1 That's why pneumatic valve "springs" have no springs. Instead, they use a chamber of pressurized nitrogen to return the valves back into the "closed" position after the cams have run their course. The diagram below (from this webpage) shows a comparison of regular valve springs on the left to the pneumatic ...


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There is an additional reason for not running lean, which applies very well to turbocharged engines - the extra fuel creates a 'boundary layer' between the combustion products and the cylinder wall. This absorbs extra heat during combustion to help keep the chamber temperature within tolerance. Modded cars that run very high turbo/supercharger boost are ...


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Lean operation vs exhaust catalysts: The three-way catalytic converter fitted to gasoline vehicles can't operate under lean engine conditions because the reaction of NOx to nitrogen and oxygen is a reduction reaction, and for this to occur there needs to be a corresponding oxidation. In the three-way catalyst that is the oxidation of CO and hydrocarbons to ...


2

Running a lean mixture by itself isn't necessarily going to cause detonation, pinging or knocking. WW2 era old timer piston aircraft pilots used to run seriously lean mixtures on long hauls to increase range and it was safe to do so when they were at cruising altitude and power settings. You'd never consider doing it in a climb or at a high power though. ...


2

I took the care to the a mechanic and they said it was or could be two things: When the battery dies sometimes the internal computer\memory needs to be reset. The car's throttle body needed cleaning. So far it has not stalled after having both of these done (5 days now). Not sure which of the above actually of the above fixed the issue ... maybe both. ...


2

One additional point to touch on is that leaner and richer are relative to what conditions the engine already runs under. In terms of chemical reactions, car engines tend to run a little rich by default -- more fuel than is needed for all of the air -- because it reduces the frequency of detonations in the mixture. If you alter things so they run leaner ...


0

It sounds as though the clutch for the fan has gone out and is now stuck, causing the fan to operate all the time (no slippage occurring). You can check to see if this is the case by opening your hood without the engine running and cold, grab the fan blade, and rotate the fan. If the fan doesn't rotate or rotate easily, this is most likely your issue.


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Lean ≠ More Air I believe the source of the misunderstanding is in how the term "lean" is being interpreted. A lean mixture doesn't indicate the presence of more air. It indicates the presence of a higher proportion of air compared to fuel (air-fuel ratio, or AFR). Quick example Mixture A has 1,000 g of air, 80 g of fuel. AFR = 1000/80 = 12.5 ...


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It's not that the catalytic converter can't handle more air per se, it's that running lean increases the temperature of combustion (I actually don't know why, but now I'm curious) and the catalytic converter needs to run inside it's chemical operating range. Something to do with the chemistry that I also don't know. As for advantages for turbo boost and ...


3

Valve guides come in several different types. Most are an interference fit. The old valve guides get driven out, and new ones driven in. This usually happens pneumatically. Some valve guides are actually screwed into place. The Jeep ones you mention, as well as most of the American made vehicles are driven in/out. There are basically three ways you can fix ...


3

What exactly is meant by cylinder head intake/exhaust port volume? The amount of air that can pass through the intake or exhaust ports as well as the amount of resistance (back pressure) that is required to get to the particular flow quantity. You are trying to reduce the back pressure (energy) required to get to your desired flow rate. There are two ...


2

From doing some reading here: http://www.jegs.com/tech-articles/cylinder-heads.html it looks like what you are referring to the size of the values and the amount of lift they get. Here's a couple of pictures that should help. This is the setup for basic overhead cam operation. Here's another, simpler diagram that shows what happens when the valves open ...


0

There is a popular process to get just about all the oil and sludge out of an engine. Though it is usually done after engine disassembly. You soak the dirty engine pieces into a hot tank of sodium hydroxide (lye) solution and other cleaning agents. The liquid will chemically react with the oils in the engine and remove it in the process.


3

The main problem would be the battery, as already pointed out. In low temperatures batteries tend to lose power, and for batteries near the end of their lifetime this means that you won't have enough current to turn the engine. Another problem would be the wrong oil chosen for the engine. Oils have grades based on their viscosity in certain temperatures - ...


4

tl dr; Yes. You can use the 307 heads on the build. Now, with that out of the way, let's talk about what you'll get with these 307 heads. Every 307 head built came with 1.72" intake valves. These are relatively tiny. In fact, from the factory, these are the smallest intake valves offered (that I'm aware of). 350's came mostly with 1.94" intake valves. The ...


5

Ice Probably the most common problem that people have is when their car is parked in a moist environment below degrees, resulting in ice forming on some or all of the windows. To resolve this problem, see this answer. Battery Another problem that is quite common (this happened to me recently), is if you have a car with a car battery that is in poor ...


2

Batteries perform better when they aren't cold so often the first time a battery fails is when it is cold so if you could heat it up a bit it would probably start the car. This may be way cars mysteriously start after sitting in the sun for a while. Also it may be harder to turn over a cold engine than a warm one so it would require a greater current draw. ...


9

Intake manifold runner length is the linear distance from the inlet port (the face of the head) to a common point shared by all cylinders. Depending on the throttle position this could be the open atmosphere (if each cylinder has its own throttle butterfly) or a plenum (if they share a throttle body). The intake runner volume is the volume of that section ...


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tl dr: Cylinder heads (commonly just called "heads") are the big piece of metal which caps and seals the end of the cylinder bore. Types of Cylinder Heads: There are three basic types of cylinder heads: Flathead Cylinder Head - These cylinder heads were used on older engines such as the flat-head Ford engines (like seen below). The oval protrusion at ...


3

What is engine coolant? Engine coolant is a water and antifreeze solution. Because water has good properties as a coolant, antifreeze is used in internal combustion engines and other heat transfer applications, such as HVAC chillers and solar water heaters. The purpose of antifreeze is to prevent a rigid enclosure from bursting due to expansion when ...


0

The reason steam engines aren't suitable for cars is mostly due to the need for steam engines to be run at a mostly consistent minimum speed, and they don't adjust speed very well. Steam engine do not need to be inefficient, but they do work best when under constant use.


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Actually, you see, the internal combustion engine replaced the steam engine to power vehicles of all kinds. It was originally used in locomotives in the 1800s to connect the east cost of the US to the west coast. They also powered paddle wheel boats up the Mississippi and allowed for powered crossings of the Atlantic Ocean. But enough of the history lesson. ...


5

In the early automotive days, steam-powered cars were more common than anything else. Disadvantages of steam power for automotive use, as compared with the internal combustion engine: Inefficiency. In an internal combustion engine, chemical energy is converted directly to mechanical energy in the form of expanding gas combustion products. Conversely in ...


4

Heat engines (in thermodynamics) convert thermal (or heat) energy to mechanical energy. Heat engines typically work by utilizing the expansion of a gas and/or liquid as it is heated. External combustion engines are a type of heat engine where the heat is produced (by combustion - burning) outside of the engine itself. From the wikipedia page: An ...


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This article pretty much covers it. http://www.popularmechanics.com/cars/how-to/a7487/should-you-convert-your-car-to-natural-gas/ tl;dr Not taking into consideration a source for CNG. You need a lot of money. You need a new fuel tank capable of holding pressurized gas up to 3600psi. A fuel regulator and new fuel injectors. As well as a tune so that you ...



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