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.
In a 4-stroke engine, there is one compression stroke for every two revolutions of the crankshaft. Since a 6-cylinder engine has six cylinders, each cylinder will have one compression stroke every two revolutions. Therefore, in one revolution of a 6-cylinder 4-stroke engine, there will be 3 compression strokes.
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.
When a jet ski has low compression in one cylinder, first, perform a compression test to confirm the issue. If low compression is verified, inspect for potential causes such as worn piston rings, damaged cylinder walls, or a blown head gasket. It may be necessary to disassemble the engine for further diagnosis and repairs. Addressing the root cause will help restore proper engine function and performance.
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.
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.
2 compression rings and one oil control ( helps scrap excess oil off cylinder walls)