Checking. Disassembling And Servicing; Engine Body - Kubota ZD221-48 Workshop Manual

ZD221, WSM
ENGINE
4. CHECKING, DISASSEMBLING AND SERVICING
[1] CHECKING AND ADJUSTING
Compression Pressure
1. Run the engine until it is warmed up.
2. Stop the engine.
3. Remove the air cleaner, the muffler and all glow plugs (or
nozzles).
4. Set a compression tester with the adaptor to the glow plug hole
(or nozzle hole).
Nozzle hole: Adaptor H (07909-31231)
Glow plug hole: Adaptor L (07909-31301)
5. After making sure that the stop lever is set at the stop position
(non-injection), run the engine with the starter and measure the
compression pressure.
6. Repeat steps 4 and 5 for each cylinder.
7. If the measurement is below the allowable limit, apply a small
amount of oil to the cylinder wall through the glow plug hole (or
nozzle hole) and measure the compression pressure again.
8. If the compression pressure is still less than the allowable limit,
check the top clearance, valve clearance and cylinder head.
9. If the compression pressure increases after applying oil, check
the cylinder wall and piston rings .
• NOTE
• Check the compression pressure with the specified valve
clearance.
• Always use a fully charged battery for performing this test.
• Variances in cylinder compression values should be under
10 %.
(1) Engine Body
2.84 to 3.24 MPa
Factory spec. 29 to 33 kgflcm
2
Compression pressure
412 to 469 psi
2.26 MPa
Allowable limit 23 kgflcm
2
327 psi
o
1-512