Questions tagged [piston]
The piston tag has no usage guidance.
63
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Do pistons keep moving when the car stops?
When you are driving and stop at a light, do the pistons still move up and down due to combustion? If not how will the engine know when to combust the fuel to keep it moving?
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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's gonna happen if I disconnect 'single piston'
I saw similar topics but that did not explain my things...
As we can see 4 stroke engine with 4 pistons
Is there any chance (only for test) to 'switch-off' two pistons?
For this example I'm talking ...
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What exactly is a "knurled piston"?
Recently I came across the term "knurled piston" and I don't know what it means.
What is a knurled piston?
What is the difference between that and a normal piston?
Why should you use a knurled piston ...
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3
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3 rings vs 4 rings pistons: which design is better?
The engine I'm rebuilding (Skoda Estelle/120, 70's, RWD, rear mounted engine) was manufactured with two different pistons, depending the fabrication years: one piston kind has 4 rings and a cut from ...
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2
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Where does the piston stop after the ignition is turned off?
Compression stroke at TDC or Exhaust at TDC or somewhere else?
Is this position fixed or does it depend on other conditions?
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3
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What is an inverted triangle piston skirt?
The recently launched Suzuki GSXR150 boasts an inverted triangle piston skirt. From what I have been told, it seems to be MotoGP technology which has been stripped down to suit a 150cc bike. Kindly ...
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2
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Safe to buy new piston for your two wheeler engine
I own a Honda Stunner 125 CC motorcycle. I bought it in 2009. Since last year I have observed that it is emitting white smoke.
Mechanic recommends that I purchase new pistons or after some time ...
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1
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Do my new oil rings have an excessive gap?
Today I measured the new piston rings I will use while rebuilding my old Skoda Estelle engine.
Skoda Set
They are new from the Skoda factory (or that's what the box says), but they were ...
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5
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2
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Cleaning pistons and cylinders with oven cleaner
Can I use oven cleaner (composition: 5-15% aliphatic compounds, 2-aminoethanol, butane and propane...) to clean the carbon off the cylinders and pistons of my BMW R80GS 1991 Motorbike (without ...
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2
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Rebuilding an engine: pistons installed, crank rotation "very" stiff
As I'm assembling my engine back (Skoda Estelle 120, 70s, RWD, rear mounted engine) I have the following issue: installed crankshaft, camshaft and distribution chain, torqued as manual recommends, it ...
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5
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2
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Pivoted curved-path piston engine
Years ago, I saw a documentary about engine efficiency where people were testing a pivoted, curved-path piston engine. The claim is that the standard piston engine, with straight up-and-down path, ...
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3
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371
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Extracting piston rod's "wire" C clips
So now that I'm getting ready (soon :) ) to fit new pistons in my old Skoda Estelle engine, I found that the piston rods have "wire" C clips. I mean, they look like a piece of wire, no "eyes" or tabs ...
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4
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1
answer
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Why is lugging hard on connecting rods?
I was researching the effects of lugging and came upon this thread, one of whose answers claims that
lugging is really hard on the connecting rods.
but without explaining why. Can you explain ...
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2
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Motorcycle 125cc question about PISTON condition and battery
Last year I bought a 125cc bike, Modenas brand, most likely unknown to you. It is a moped.
http://www.modenas.com.my/v2motorcycle.asp?id=70
It can go as fast as 110 km/h enough for the city,
...
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1
answer
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Pistons ordeal: more pistons problems; two issues in one question
So, still having problems rebuilding this old engine (Skoda Estelle 120, 70's, RWD, rear mounted engine). First of all: getting new parts is out of the question since I have no access to those. So I ...
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1
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Rebuilt engine started, but with strong clanking sounds
So this is another question about my Skoda Estelle engine rebuild project. Now it cranked and started, after a session of neither of those. To fix that problem I released the head bolts and retorqued ...
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3
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2
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piston damage impact
something got in and caused these scratches.
can/will they cause blowby if reused?
I figure if the placement of its .018 mil piston ring gaps matter, then the gaps from these scratch just may as well....
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3
votes
1
answer
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Is it really necessary to resurface cylinder and substitute piston?
I believe this is common in motorcycle maintenance, I have heard in some places that, once you get the piston outside the cylinder there is no way back, you need to resurface the cylinder and get a ...
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1
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1986 El Camino: deprecation
I have a question about my 1986 el Camino, as relates to how much it has or hasn’t been damaged after a 6 month hiatus from action.
Last July I bought a 1986 el Camino from a private seller. The ...
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1
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Can one detect coolant leak due to blown head gasked by visual inspection of pistons/spark plugs?
I have problems with my 2004 Honda Civic. My engine overheats and there is no hot air coming to the cabin, even if the temperature gauge shows Hot. Every mechanic I know told me that it is a clear ...
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2
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Rear brake piston hard to turn back in, uneven wear on pads
2010 Toyota Matrix, Manual, Base model 1.8 L
Some context
It was time to replace the rear brakes (noise, grinding). When I took everything apart, I found that the inner pads were extremely worn, at ...
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2
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Should I remove the rings when cleaning a piston?
I want to clean my piston in a small ultrasonic cleaner (with distilled water). Do I need to remove the piston rings to do so, or can I leave them on and make sure it dries completely?
If I replace ...
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1
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How much force is needed to push a piston down? [closed]
Combustion from fuel and air is used to push a piston down. When they combustion it creates a lot of force, my question is how much force is needed to push the piston all the way down when the vehicle ...
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1
answer
132
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When switching off the engine, do the cam and crank shafts always come to rest in an initial state?
Is it the case, when the engine comes to a halt, that the cylinder/piston/valve phases always finish up in the same starting or initial position relative to each other?
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Can the bottom of a piston be scratched and not damage the cylinder?
I went to a mechanic and he showed me this custom piston made out of molten car pistons (there was no other option in this case). My question is:
Is the scratch from the side of the piston going to ...
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2
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Does substantially increased compression test numbers after adding oil to the cylinder necessarily imply that piston rings and/or cylinder bore is bad
SOLUTION: The tubes on the top of the motor for the PCV system were backwards. See https://invidious.fdn.fr/watch?v=07ssRI8k81E for correct configuration. Oil would pool in the air intake until you ...
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2
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333
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How to clean up carbon
I was wondering what the best way to clean up carbon off of the Pistons and valves is since I have to change 2 head gaskets
I heard abrasive cloths and cleaners aren't so good for the piston heads, ...
user38183
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1
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Piston deck clearance: is 1.4 mm under deck too much?
I'm installing a piston set in a Skoda Estelle 120 engine. I know this is not a definite way to measure piston to deck clearance, but it jumped to my mind to measure it with a vernier caliper using ...
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2
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0
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Finding rig gap specifications of old engine
I am currently restoring an old Briggs & Stratton engine. I found that it burns a little bit of oil and also saw that the head was oily after removal. I removed the piston and checked the ring gap ...
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2
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0
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Likelihood of every piston ring corroding the same rate
I performed a rebuild of my both cylinder heads on a V6 engine, in order to grind leaky valves. I performed a test of each valve pouring isopropyl alcohol in the intake/exhaust chamber and waiting ...
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2
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0
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392
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Does a 2-stroke engine needs "break-in" after replacing cylinder and piston?
I just replaced cylinder and piston (with new gasket, rings, etc) in a 2-stroke 52cc string trimmer engine. It started at the first pull and sounds great, I let it run for 5 minutes, adjusted the carb ...
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0
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Bent push rod, valve bent as well?
so i finally got around to opening up the head of my lawn mower and found out why it wasnt running.
the intake push rod is bent. and the exhaust is straight. obviously my valves were way out of spec ...
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0
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Modify (cut) piston skirts: does it also cuts its lifespan?
I'm temped, as a challenge to a problem that raised when getting ready to assemble my engine, to modify the pistons skirts since one of the pistons got a crack in the skirt, under the pin side. I see ...
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Fourth piston isn't sparking so car is losing power
What are the possible reasons that my fourth piston is not sparking. I am pretty sure the spark plug is broken but I am not sure. The car is a 2006 Scion XB.
Thank you.
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3
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Is it possible to repair a piston in an engine
Continuing from my previous question (here) one of the pistons have no combustion and so the car is only working with three pistons, and there is a sound like a piece of metal smacking against ...
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1
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How much should you clean dirty pistons and valves when you aren't removing them?
I took the heads off so I could get some broken exhaust manifold studs out and retap (actually I was advised to use a Heli-Coil instead so doing that) one of the other stud holes.
The piston heads and ...
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1
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Piston Ring Replacement Checklist
I confirmed that my piston rings were leaking after moisture got in and corroded them when I had the heads off. It's a 2007 Toyota Tacoma V6 4L. I took the diff and oil pan off, sent air through spark ...
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1
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Testing piston ring
One of my cylinders is leaking and I have determined so far that at least one or both of the intake valves are leaking. However, now that I have that cylinder head off, I would also like to test the ...
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5
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Do you have to machine the crankshaft after a spun main bearing?
I had a spun main bearing due to low oil, the crankshaft journal is pretty scratched, no dents just looks spun on the surface.
To the inexperienced diyer it's hard to imagine this would be a huge ...
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2
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How are compression rings lubricated?
My question relates to the lubrication of cylinder walls and piston rings. It is my understanding that pistons in cars consists of 3 rings; two compression rings and the oil/scraper ring.
As far as I'...
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Briggs & Stratton 33R877 Engine Problem
May I please receive help in solving an engine problem? I have a Briggs & Stratton 33R877 engine (ride mower), and it is blowing air out of the carburetor. Here is what I've done so far:
Piston ...
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1
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Piston ring gap
Does this look like too big of a gap on my old to compression piston ring?
It measures more than 0.04" (I stacked a 0.02 and a 0.021 feeler gauges together) but I could not find a specification ...
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1
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Grinding/rattling Noise from engine accelerating on both idling and driving Suzuki G10 3-cyl Engine
I am facing an issue of a rattling/grinding noise from engine left/lower side particularly in warm engine. Car is Suzuki cultus with 3-cylinder non-efi G10 engine and running on petrol. Inside cabin ...
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1
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How does enough oil remain after combustion to lubricate during exhaust stroke
To my understanding, cylinder walls are lubricated by retaining a tiny amount of oil in the honed or otherwise manufacturing prepared cavities in the cylinder walls, so that when the piston rings ...
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2
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Lancer 2004 Piston Slap Concern
So yesterday i figured out my car has a piston slap because it keeps ticking during a cold start and goes away after warming up. Car is a lancer 2004 and has 260k KMs. I changed the engine oil to 20w-...
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0
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Brake caliper piston larger than brake pad?
Upgrading my '17 Toyota RAV4 LE to the 296 rotors, which include bigger calipers and brake pads.
On the new calipers, the piston is larger than the brake pad and im not sure if thats normal? I tried ...
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vote
1
answer
397
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Piston too tight?
I am rebuilding a previously seized engine and after sanding the sidewalls of the cylinder and piston with 1500 grit sandpaper (there was absolutely no other choice) The piston requires much force to ...
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0
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What is the plastic plug for on the bottom of an SU HS4 Carburettor Piston?
Please could somebody explain the purpose of this plastic plug on the bottom of my SU HS4 carburettor piston? The lip of the plug protrudes very slightly from the bottom of the piston (shown bottom ...
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2
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Testing piston rings by pouring isopropyl alcohol in cylinder chambers with heads off
I took cylinder heads off for some maintenance, grinding valves among others to improve compression. I tested the valve seals by pouring isopropyl alcohol in intake and exhaust cavities and waiting 12-...
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