Questions tagged [valve]
Refers to engine intake or exhaust valves.
22
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Hole-in-One. Small extension and socket fall into valve
I am very poor so I work on my house/SUV (2002 Ford Expedition) myself. Recent misfires had me changing coils and spark plugs. Well, everything is going fine until my extension comes off my socket ...
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What is valve float and how does it impact engines?
The Wikipedia entry is hard to grok:
Valve float is an adverse condition which can occur at high engine speeds when the poppet valves in an internal combustion engine valvetrain do not properly ...
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What exactly is a "burnt valve" and what causes it?
I've come across this term a couple of times in the context of diagnosing engine-related issues, but don't know what it refers to. Here is an example from an automotive forum I frequent:
I gotta ...
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Why did Ducati decide to use the desmodromic valve train rather than a more tradition valve train?
Ducati's use a unique method to open and close their valves. It's called the desmodromic valve train.
The desmodromic valve system does not use springs to close the valve, it uses the cam and has a ...
- 33k
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Interference vs non-interference engines
What do people mean when they say that an engine has an interference design? How does it differ from a non-interference engine?
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What are the various kinds of tappets / lifters and the advantages / disadvantages of each
A previous question about tappets found here:
What are Tappets?
covers the basics of tappets. If we go the next step, here are my questions:
What are the various kinds of tappets / lifters?
What ...
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1
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Do I risk damaging the valve seat if I lap this valve without removing carbon build-up?
This valve is from my LS1 (Exhaust #3). It's suffered from a lot of carbon build-up due to a history of fueling/spark problems.
I've tried cooking it in ethylene glycol. I've tried using abrasion ...
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Reliability of water test for valve seal
I took my valves out, cleaned and lapped them and put them back together. I also put new valve stem seals. At least on one side of my V6 Tacoma.
I performed several water tests to check the seal of ...
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1
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Effects of intake valves leaking
I just measured cylinder leakdown rates on my 2007 Tacoma V6. 5 out of the 6 cylinders had retention rates of 75-85% (leaking 15-25%) but my cylinder 4 (left engine bank in the middle) was leaking ...
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"Valve like" noise after modifying camshaft ninja 300
A friend and I bought a modified camshaft for his ninja 300/EX 300.
After installing and checking/adjusting valve clearance everything seemed ok.
After a few laps on our local track the bike started ...
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Pneumatic Valve Spring Operation in Formula 1
In the 2006 Formula 1 World Championship the rules allowed for pneumatic valvesprings.
These engines were required to have a 90° V8 engine with 2.4 liters of displacement, 4-valve-per cylinder layout ...
- 33k
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What are the causes of fluctuating intake manifold vacuum
I have a 2005 Honda CBR600 F4i which suffers from occasional hesitation at low rpm when accelerating. I also get occasional fault codes from the ECU indicating a vacuum leak.
Today I connected a ...
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2
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Help me diagnose the cause of this intake valve burn
I would like some help diagnosing the probably cause of this intake valve burn as seen in the picture.
167fmm engine.
229cc OHV push rod type.
Now here is the rub.
this is engine originally 9:1 CR, ...
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1
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This valve is pitted - what options do I have?
This is that infamous Exhaust Valve #3 after cleanup. The cylinder had a history of fuel/spark-related misfires.
As the images show, the lip of the valve is pitted.
Here is the back of the valve.
I ...
- 39.1k
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1
answer
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XJ600 1994 Seca 2
I am wondering if anyone can shed light on an issue we are having with this particular bike. Basically, the bike starts fine cold and warms up and drives perfectly for about 15 minutes ( responsive to ...
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1994 Honda Accord EX (F22B1) - Valves still making a ticking noise
I have a 94 Honda accord Ex (F22B1). When I bought it a few days ago the previous owner mentioned a few of the issues that he could remember. Since I've only ever owned Honda's and have worked on them ...
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Should I care about valve order or are they interchangeable?
So I've just learned how to take valves down and I'm pretty fascinated by the whole mechanism. I got a C-clamp compressor and took two valves out just to try. Went smooth.
A question: is it important ...
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2
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Compression of valve springs and camshaft rotation
As you know, in most cars it is not easy to turn the intake or exhaust camshaft by hand. You probably need to use both hands, grab the cam sprocket and apply a lot of force to rotate them even with ...
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Why are intake valves dirtier than exhaust?
I took my engine apart and one of the things I noticed, on both cylinder heads of my Tacoma V6, is that the intake valves (picture right) are significantly darker (or dirtier) than the exhaust ones (...
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1
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Leakdown Test | EJ205 on Engine Stand and replaced all Valves
I have my EJ205 out of my 2003 WRX. I pulled the engine in the first place to troubleshoot a 90% pressure loss in Cylinder 4 (measured via a leakdown test with the Engine still in the car). The ...
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Do you have to remove the heads to replace the lash adjuster on a 2002 Ford Escape?
Hello I guess I'm replacing a lash adjuster today. Before I start I'd like to get a better idea of what I'm getting myself into. I know that you're supposed to replace all of them at once and that you ...
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Initial reassembly valve leak to be overcome by breaking in
I lapped my valves and got good results testing both off the engine (pouring alcohol in intake/exhaust chambers and waiting to see level unchanged) and on (cylinder leakdown test). However, as soon as ...
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