25

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 the ...


11

There are a few factors to consider. Ease and cost of mass-production. Individual barrels require individual assembly, whereas a cast piece of metal has a lot of things built-in and assembly can be automated much more easily. Durability. Engines make vibration, that can't be helped. A solid piece of metal can both handle and channel this better than ...


10

As @rpmerf says, virtually all piston engines have at least one cylinder head. Most engines will have one head per bank of cylinders, as you suggest, though some have more - IIRC some of the aircooled VW engines had one head per cylinder. There are however some that don't have any - in opposed-piston engines, such as the two-stroke Napier Deltic and the ...


8

Compression test is more to test if there is a problem. If your compression is low, it could be a number of different issues. You can test the rings by adding oil to the cylinder and see if the compression is higher. Other than rings it can be difficult to determine the source of the issue. A leakdown test will tell you where the problem is. By watching ...


8

It is ALWAYS good to get a second opinion. I would highly recommend taking it to another shop and have them tell you what they think it is even if you believe the first shop to be right. That being said, there are a couple of things you can do at home to try and diagnose a head gasket problem yourself. Look to see if white smoke is coming out of the ...


7

All piston engines must have a cylinder head. The head is on top of the block and forms the top of the combustion chamber. The head is also where the valves are. The valves and chambers in the head allow air/fuel to enter the combustion chamber and exhaust to leave the combustion chamber. The head is removable to allow for assembly and maintenance.


7

It's completely normal, nothing to worry about It's simply the gap between the sleeves. If you look from above, straight down, you will see a straight edge cut into the outside diameter of the metal sleeves that are pressed into the aluminum cylinder block. The straight edge is there so the sleeves can co-exist in close proximity without encroaching into ...


7

You might get away with it, but I sure wouldn't recommend trying. The risks just seem too high. Instead try either blowing air into the cylinder with a small tube (to leave room for the shell to come out), or sucking it out with a vacuum connected to a small hose. You may have better luck if you turn the engine over by hand to bring the piston up near the ...


7

Your Passat uses torque to yield bolts, so they must be replaced. The torque to yield bolts are considered "one and done". This is because during the torquing process, they are stretched beyond deformation, past their plasticity. If you try to use them again, they will fail. If you reuse them, not only will they fail, but you will most likely cause damage to ...


6

Yes you can. Obviously you'll be at a reduced power level, but no problems should occur from doing this. EDIT: While I believe this is a "plug on" application, you'll want to ensure your coil is not connected either. I doubt it will be down in the hole, but you don't want to have the coil attached to the wiring harness without it being able to throw ...


6

You shouldn't sand the block at all unless there is existing damage of some kind - but it really doesn't take much to damage, even a fine scratch can ruin the seal for the gasket. If you have to sand it, you will have to finish it to quite a fine grade and be very careful about keeping the surface relatively even/level. If you are very careful, you can use ...


6

This, in and of itself, is nothing to be worried about. The reason I say this is, it is not part of the sealing surface for a cylinder. There is more than enough meat there to seal the cooling port, as long as there isn't a crack from there radiating out. You will most likely want to have the head resurfaced, even if it is only to clean up the mating ...


5

It's fine I did a similar job on a 2003 model recently. I kid car. Luckily, I didn't have any bent valves to deal with. Turning the engine over with the head off and the car in gear won't hurt anything. I know the exact feeling of elasticity you are talking about if you have the car in gear. I am assuming you had the front wheels on the ground when you ...


5

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 ways ...


5

From what I understand the answer to this very simple and logical. When someone might be attempting to DIY a fix and have a particular socket that fits a nut, they may just turn it not realizing what loosening the bolt may do. As a result there are less accidentally loosened head bolts. If you are a DIY person, which I am, I don't have a real issue with ...


5

I would not use assembly lube with the valves (in the valve guides), but just oil there. The reason for this is because there is no way to flush the assembly lube out of this orifice like there is in other places throughout the engine. My preference is to use assembly lube for the rest of the parts. Assembly lube will keep the parts from chafing (wearing ...


5

Most modern car engines have overhead camshafts. Overhead camshafts pretty much oblige the use of a one-piece cylinder head. Imagine the difficulties of aligning the camshaft if each cylinder had a separate cylinder head. It's easier to seal the cooling and oil passages of a water cooled engine if there are less joints. Less components also means faster ...


4

The engine is unlikely to be damaged. This is not true for the catalyst. With one cylinder pumping air into the exhaust the mixture sensors (oxygen sensors) will see this as a lean condition and try to compensate by enriching the others on that bank. This results in a uneven mixture at the catalyst, which can damage it. It OK to drive to the shop of your ...


4

One thing worth mentioning is that running with a missing cylinder will result in engine vibrations that will be felt across most of the rev range. This will not cause damage in the short term, but will make for a rather annoying driving experience.


4

Realistically, you haven't added any extra life to the vehicle itself. The vehicle is a combination of it's sub-parts (ie: engine, transmission, differential, etc.). Any part at any time can fail for whatever reason. Even the engine is made up of sub-parts to create it's whole. You have definitely given the heads longer life, but you still have the rest of ...


4

Having had to work in tight spaces, I say it's very useful to have a bolt which you can turn in less than one-sixth turn. What I mean is, that bolt can be turned with a common hex tool, but sometimes you don't have the freedom of movement to rotate it 1/6, this way you can find the position that suits you best. Hope I've been clear enough, sorry if I have ...


4

It is OK to used a metal tool on the valves. They are very hard and difficult to scratch. It is also OK to use oven cleaner on the valves. The steel is a relative of stainless and will be little affected by harsh cleaners. This is not true for the aluminum head and the valve seats are usually softer than the valves but are still hardened steel.


4

The pressure generated at Top Dead Center on the Power stroke is very high. A "taller" gasket will have a larger cross-sectional area exposed to this pressure, so high "pounds/sq inch" grows proportionately as the area increases. Even the best Multi Layer Steel head gaskets are not designed to be part of the cylinder, just to seal the head to the block. ...


4

Wouldn't hurt to get a second opinion. However, be careful if you try diagnosing yourself. If coolant is leaking into one of the cylinders and you try starting the car you could hydro-lock the engine and bend a connecting rod which is obviously more money to fix. Before turning over the engine, pull the spark plugs out and turn the engine over by hand ...


4

This valve can absolutely be salvaged. You just need a valve job. You can have a look at what's entailed in a valve job by watching this Jafromobile video. To the uninitiated, I won't go through all of the steps involved, but I'll go over some of the pertinent points so you'll understand why this will work for you. During a valve job, there's two basic ...


4

There are a limited number of places where combustion gasses can get into the coolant. A cracked head is the obvious one. It is also possible that it is a crack in the block going from the cylinder into the water jacket. You could use an exhaust gas analyser to sniff the bubbles in the expansion tank to verify that it is exhaust gas coming through.


3

is there any sealant to stop engine oil leak to radiator No. or do I need to replace cylinder-head-gasket? Yes. But also you need to have the head and the block checked for warping. They head might need to be re-surfaced.


3

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 and ...


3

As Brian commented, your question and the information we have is a little vague. Not repaired already: It won't drive at all if the timing chain is broken. No amount of cranking the engine will start it. For this year/make/model it would probably be cheaper to either purchase another vehicle or swap in a low mileage engine than repair the current one. If ...


3

Those are engine head bolts and need to be torqued precisely, in order to last their useful life. Since they are located in an awkward location and have to be assembled in a factory, I suppose they are using double-hex heads to allow for greater torque, despite the complexity of having different tooling. Otherwise they would use simple outer hex bolts. Such ...


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