Removal and Replacement

CYLINDER HEAD


Removal and Installation












REMOVAL

WARNING:
- Put a "CAUTION: FLAMMABLE" sign in the workshop.
- Be sure to work in a well ventilated area and furnish workshop with a CO2 fire extinguisher.
- Do not smoke while servicing fuel system. Keep open flames and sparks away from the work area.
1. Release fuel pressure. Testing and Inspection.
2. Drain engine coolant and engine oil. Changing Engine Coolant and Draining.

CAUTION:
- Perform this step when the engine is cold.
- Never spill engine coolant and engine oil on drive belt.
3. Remove the following components and related parts.
- Front fender protector (RH). Removal And Installation.
- Generator. Service and Repair.
- Exhaust front tube. Component.
- Exhaust manifold. Exploded View.
- Intake manifold. Exploded View.
- Fuel tube and fuel injector. Exploded View.
- Water outlet. Removal And Installation.
- Drive belt. Removal and Replacement.
- Front cover. Exploded View.
- Camshaft. Exploded View.
- Air cleaner assembly. Removal And Installation.









4. Remove cylinder head loosening bolts in reverse order as shown.
5. Remove cylinder head gasket.

INSPECTION AFTER REMOVAL

Cylinder Head Bolts Outer Diameter





- Cylinder head bolts are tightened by plastic zone tightening method. Whenever the size difference between "d1" and "d2" exceeds the limit, replace them with a new one.






- If reduction of outer diameter appears in a position other than "d2", use it as "d2" point.

Cylinder Head Distortion

NOTE:
When performing this inspection, cylinder block distortion should be also checking. Cylinder Block.
1. Wipe off engine oil and remove water scale (like deposit), gasket, sealant, carbon, etc. with a scraper.

CAUTION:
Never allow gasket debris to enter passages for engine oil or engine coolant.





2. At each of several locations on bottom surface of cylinder head, measure the distortion in six directions.











- If it exceeds the limit, replace cylinder head.

INSTALLATION
1. Install new cylinder head gasket.









2. Tighten cylinder head bolts in numerical order as shown with the following procedure to install cylinder head.

CAUTION:
If cylinder head bolts are re-used, check their outer diameters before installation. Follow the "Cylinder Head Bolts
Outer Diameter" measurement procedure.
a. Apply new engine oil to threads and seating surfaces of bolts.
b. Tighten all bolts in the specified order.










c. Turn all bolts 60 degrees clockwise (angle tightening) using Tool
(A) in the specified order.

CAUTION:
Check and confirm the tightening angle by using Tool (A) or protractor. Avoid judgment by visual inspection without the tool.






d. Completely loosen all bolts in reverse order.







CAUTION:
In this step, loosen bolts in reverse order of that indicated.
e. Tighten all bolts in the specified order.










f. Turn all bolts 75 degrees clockwise (angle tightening) using Tool
(A) in the specified order.

CAUTION:
Check and confirm the tightening angle by using Tool (A) or protractor. Avoid judgment by visual inspection without the tool.






g. Turn all bolts 75 degrees clockwise again (angle tightening) using Tool (A) in the specified order.

CAUTION:
Check and confirm the tightening angle by using Tool (A) or protractor. Avoid judgment by visual inspection without the tool.
3. Installation of the remaining components is in the reverse order of removal.

INSPECTION AFTER INSTALLATION
- Before starting engine, check oil/fluid levels including engine coolant and engine oil. If less than required quantity, fill to the specified level. Maintenance
- Use procedure below to check for fuel leakage.
- Turn ignition switch ON (with engine stopped). With fuel pressure applied to fuel piping, check for fuel leakage at connection points.
- Start engine. With engine speed increased, check again for fuel leakage at connection points.
- Run engine to check for unusual noise and vibration.
- Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids including engine oil and engine coolant.
- Bleed air from passages in lines and hoses, such as in cooling system.
- After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to specified level, if necessary.
- Summary of the inspection items: