most likely a valve is not seated,burned or 'missing'.. i.e 'dropped valve' this swopuld have made an obvious noise when it happened! if any of these are happening, the piston chamber will not seal... hence no compression.. another possibility is a hole in the piston itself ...
Depends on why there is no compression.
Oil burning or loss of compression on any one cylinder. It may also be missing on one cylinder. A compression test will verify this.
Low compression in one cylinder can mean several things. The valves or piston rings may need to be replaced. There may be a crack on the engine, or the head gasket may have blown. The engine should be diagnosed properly to see what exactly is the cause of the low compression.
Number one cylinder is located driver's side front of engine. With the # 1 piston at TDC on the compression stroke, the rotor will be pointing at #1 plug on cap.Number one cylinder is located driver's side front of engine. With the # 1 piston at TDC on the compression stroke, the rotor will be pointing at #1 plug on cap.
The compression can be different from one engine to the next depending on mileage and maintenance. What is important is that all cylinders are within 10/15 lbs of each other.
Depends alot on the year, and how many miles on the motor. Anywhere from 80lbs, and up. What you are really looking for, is a difference. One cylinder 25, or 30 lbs lower. This would indicate a dead cylinder.
It varies from one engine to the next but, what you want to see is that all the cylinders compression readings are within 10% of each other.
The easiest answer is when it fails a compression test. Buy a compression tester (farily cheap), and test each cylinder. If one single cylinder is below 120 psi, or if one cylinder reads 15% less pressure than the cylinder with the highest pressure, your engine should be torn down and checked. The problem might only be in the heads, but it's still time for some serious work.
2 compression rings and one oil control ( helps scrap excess oil off cylinder walls)
How do you fix no compression in one cylinder? Yes, a dead cylinder can be fixed by checking and rectifying any defective component that falls among some of the reasons that result in a dead cylinder; in order to fix a dead cylinder, you will have to diagnose the cylinder by using a compression gauge to test whether there are any cylinders with no compression. Usually, a leaking gasket.
On one or all cylinders? a single cylinder compression loss may be a stuck or bent valve, or even bad piston rings. Engine wide would have to be some kind of massive valve train failure.
Most of the times when you have low compression on one cylinder it's an indication that the head gasket is blown. If more than one cylinder has low compression and is hard to start the you most deffinatly have a blown head gasket