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16 votes
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Why when I turn the front wheels by hand, the crankshaft doesn't rotate?

Between the engine and transmission assembly (or part of the transmission assembly) there is a set of gears called the differential. Its purpose is to enable the outside wheel faster rotation when ...
fred_dot_u's user avatar
  • 4,640
7 votes
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Are valve shims re-usable?

Yes, shims are reusable. Since they are between two pieces of metal and suffer no fatigue or wear, as long as they look good and measure out good (are concentric), there should be no issue using them. ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes
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Preventing debris from falling in engine while changing valve cover gasket

Yes, debris will cause damage, however the valves cover gasket doesn't stick that hard and if it is the original, they come with some kind of rubber material, very easy to take out even in one piece ...
Aram Alvarez's user avatar
  • 3,346
6 votes
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Reusing valve stem seals

Well, if you believe the seals are in good shape, there's nothing saying you can't reuse them. However, considering you have it all apart and the seals are relatively cheap considering the amount of ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
5 votes

Reusing valve stem seals

As inexpensive as those seals are, and as hard as they are to get to, you should absolutely replace them. Do not reuse them.
zipzit's user avatar
  • 6,569
4 votes
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Can I use hard tools to remove hardened carbon buildup on valves?

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 ...
Fred Wilson's user avatar
  • 11.6k
4 votes
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Why a two-lever valve spring compressor?

Doesn't appear to have a special purpose other than convenience. According to the Draper Tools Website; Suitable for use on most engines due to double-ended valve cup. Unique double action lever ...
CharlieRB's user avatar
  • 9,015
4 votes

Are there any downsides to the Coates valvetrain?

Volumetric Efficiency The primary limitation would be the intake charge timing. The rotating chamber for the intake charge is limited to the volume of the chamber rather than the poppet valve style ...
DucatiKiller's user avatar
  • 32.9k
4 votes
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This valve is pitted - what options do I have?

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 ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes
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Would using a cooler plug help or even prevent this level of exhaust valve damage

From what I understand of cool/hot spark plugs, the idea is not that they are absorbing a significant amount of heat that would otherwise be burning your valves. Cooler plugs keep the tip of the plug ...
Zshoulders's user avatar
  • 1,646
4 votes
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Lapping valves by hand - does the compound have to be cleaned off?

Yes, remove all traces of the lapping compound - it is the metal to metal joint between the mating faces that is being tested.
Solar Mike's user avatar
  • 34.6k
4 votes

Should I be concerned about eccentric valve rotation?

The part you don't show on this exhaust valve which is much more important is how the lapping ring looks on the valve. If the ring which shows the lapping looks even all the way around on both the ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes

Lapping valves by hand - does the compound have to be cleaned off?

Not only should it be cleaned off, you want to ensure you don't get/leave any on the valve stems. You'll wear out the valve guide in short order if you don't. Remember in engine building, cleanliness ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes
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Is there clearance for the valves to go, in case of busted belt on a C4 1.4 V16 2005

You probably have the ET3 engine which is the 16-valve version of the TU3 with variable valve timing. Unfortunately I believe it is an interferance engine. http://www.saxperience.com/forum/showthread....
willpb's user avatar
  • 310
4 votes

Hole-in-One. Small extension and socket fall into valve

Unfortunately as you say you have turned the engine over for 10 seconds you may have seriously damaged both the piston and cylinder head etc. Not to mention the bar with 8mm socket attached, which ...
Orb's user avatar
  • 5,067
4 votes

Can I remove the valve cover to retrieve the extension with 8mm socket that fell into my engine?

You need to get into the combustion chamber so the head needs to come off - the valve cover is one of the preliminary steps... Edit due to your duplicate post... I suggested a magnetic tool and you ...
Solar Mike's user avatar
  • 34.6k
4 votes

Valves in pizza box fell out does order matter if lapping

Lapping won't solve your issues. The only thing you can do is get the valves back in the right order or take it to the machine shop and get a valve job. The problem is, the valves are matched to the ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes

Lapping valves by hand - does the compound have to be cleaned off?

Yes it must absolutely cleaned off. The compound is an abrasive paste, as such on initial start up it will be ingested into the engine. The outcome would be the same as leaving some fine sand on the ...
mikes's user avatar
  • 20k
3 votes
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Tyre Valve Pin Too Far In

You could buy a similar length new valve stem (about $1), and swap out the cores to see if that helps the situation. If it doesn't, you'll have to get the valve stem replaced. Quality control on ...
SteveRacer's user avatar
  • 12.4k
3 votes

Lapped valves still leak but slowly

Yes, it seems to be uneven springs, however I rotated each valve a couple of times left/right, with the springs in their positions, and now non are leaking. My test was: put the spark plugs and the ...
Aram Alvarez's user avatar
  • 3,346
3 votes

Lapped valves still leak but slowly

you need to look up the proper spring pressure for your engine. I can say with near certainty it sounds like your springs are bad. How are you doing a leakdown test? If it is with the head on the ...
Cc Dd's user avatar
  • 2,879
3 votes
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Stuck valve, loss of pressure. Risky or only poor performance?

The longer you run it, the more damage you are going to cause. This will incur more cost when you do go to get it fixed due to the parts involved. Depending on which valve(s) is (are) sticking, you ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes

Preventing debris from falling in engine while changing valve cover gasket

Any debris will cause abrasive damage: the bigger the debris, the bigger and quicker the damage will be. Other than being careful, you can always cover up the engine if you are working in a dirty, ...
tlhIngan's user avatar
  • 12.2k
3 votes
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If I'm lapping valves do I need to replace piston rings?

Absolutely not. One has nothing to do with the other. If there are reasons to change the piston rings, then by all means change them. Things like blowby and/or oil consumption would be reasons. Not ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes
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Probably Tappet noise in my brand new yamaha fz fi

Yes of course. The valve clearances may move during first usage period as they settle. It is fine to adjust the valve clearances and the tappet noise should reduce. Excessive tappet noise can be ...
r.anderson's user avatar
3 votes
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Leakdown Test | EJ205 on Engine Stand and replaced all Valves

You state you "lapped the valves" when replacing them? If you have replaced the valves, you need to do more than just lap the valves. You actually have to do a valve job. This entails ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes
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Which part of the valve stem do i need to replace?

Yes, you need to have the whole thing replaced. That appears to be a stem for a tire pressure sensor. In order to fix this, you'll have to have the tire broke down, then pull the sensor off the rim. ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes
Accepted

Stuck valve in lawn tractor Briggs & Stratton OHV

It looks like the valve guide has move out of the head. It is as you have described a sleeve that the valve stem slides in. The valve guides are pressed into the head and should stay there. Other ...
HandyHowie's user avatar
  • 25.4k
3 votes
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How much should you clean dirty pistons and valves when you aren't removing them?

You can do as little or as much as you want, it is your engine. Since you have already done a load of work disassembling the engine, to me it would make sense doing as much as you can while it is in ...
HandyHowie's user avatar
  • 25.4k
2 votes
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Where do you install cylinder heads, camshafts and valves in different engine types?

This will be for modern car engines. This does not necessarily include motorcycle, 2 stroke, or equipment (lawn mower), etc.. This is based on what I've seen so there may be other examples I am not ...
rpmerf's user avatar
  • 8,403

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