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3.
Clogged oil gallery or metering orifices.
No Oil Pressure
1.
Low oil level.
2.
The lubrication oil pressure valve is stuck and closed.
3.
Damaged oil pump.
4.
Incorrect oil pump installation.
5.
Internal oil leak.
Oil Level Too Low
1.
The lubrication oil does not keep at the normal level.
2.
Worn piston rings.
3.
Worn cylinder.
4.
Worn valve guides.
5.
Worn valve guide seals.
6.
Piston rings incorrectly installed during engine overhaul.
7.
External oil leakage.
8.
Oil leaking into the cooling system.
Oil Contamination
1. Blown head gasket allowing coolant to leak into the engine.
2. Coolant leak.
3. Oil and filter not changed at specified intervals or when operating conditions demand more
frequent changes.
A cylinder leak down test can accurately pinpoint engine leakage problems from the head gasket,
water jackets in the cylinder head and cylinder, valves and valve seats, and piston rings. This test is
performed by applying compressed air to the cylinder through a special tester and then measuring the
percent of leakage. A cylinder leak down tester and an air compressor are needed to perform this test.
When performing a leak down test, the engine is first set at TDC on its compression stroke so that
all the valves are closed. When the combustion chamber is pressurized, very little air should escape.
However, the difficulty in performing a leak down test on a single cylinder engine(especially on the
engines described in this manual with low static engine compression) is in preventing the piston from
moving as the combustion chamber starts to pressurize. Any piston movement will force the crankshaft
to turn away from TDC and allow air to escape past an open valve seat.
In this procedure it will be necessary to lock the engine at TDC on its compression stroke and
then perform the leak down test. Follow the manufacturer's directions along with the follow the
manufacturer's directions along with the following information when performing a cylinder leak down
test.
1.
Support the UTV on a work stand with the rear wheel off the ground.
GENERAL INFORMATION
CYLINDER LEAK DOWN TEST
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Troubleshooting
