Valve: Service and Repair

VALVES AND VALVE SPRINGS
The valves are arranged in line in the cylinder heads and inclined 18 degrees. The valve guides are pressed-in powder metal inserts in the heads.

REMOVAL






1. With cylinder head removed, compress valve springs using Valve Spring Compressor.
2. Remove valve retaining locks, valve spring retainers, valve stem cup seals and valve springs.
3. Before removing valves, remove any burrs from valve stem lock grooves to prevent damage to the valve guides. Identify valves to insure installation in original location.

VALVE INSTALLATION
1. Coat valve stems with clean engine oil and insert them in cylinder head.







2. If valves or seats have been reground, check valve tip height (A) and valve spring installed height (B). If valve tip height is greater than 49.53 mm(1 61/64 in.)grind valve tip until within specifications. Make sure measurements is taken from cylinder head surface to the top of valve stem.






3. Install valve spring seats over valve guides and new seals on all valve stems. Install valve springs, valve retainers.







4. Compress valve springs with a valve spring compressor install locks and release tool. If valves and/or seats are reground, measure the in- stalled height of springs (B), make sure measurements are taken from top of spring seat to the bottom surface of spring retainer. If height is greater than 42.65 mm (1.670 inches), in- stall a .794 mm (1/32 inch)spacer in head counter- bore under the valve spring seat to bring spring height back to 41.85-43.44 mm (1.648 - 1.710 inches.).


REPLACE VALVE STEM SEALS OR VALVE SPRINGS - -CYLINDER HEAD NOT REMOVED

1. Perform fuel system pressure release procedure before attempting any repairs.
2. Disconnect negative battery cable.
3. Remove secondary ignition wires, spark plugs and engine valve covers.
4. Remove connector wire from ignition coils.
5. Using suitable socket and handle at crankshaft pulley retaining screw, turn engine so the number 1 piston is at Top Dead Center on the compression stroke.
6. Remove rocker arms with pivots. The rocker arms should not be disturbed and left on pivots.
7. With air hose attached to spark plug adapter installed in number 1 spark plug hole, apply 90 to 100 psi air pressure (620.5 to 689kPa). This is to hold valves into place while servicing components.
8. Using a suitable tool compress valve spring and remove retainer valve locks and valve spring.
9. The intake and exhaust valve stem seals should be pushed firmly and squarely over the valve guide using the valve stem as guide. Push seal against top of guide. When installing the valve retainer locks, compress the spring only enough to install the locks.


CAUTION: Do not pinch seal between retainer and top of valve guide.

10. Follow the same procedure on the remaining 9 cylinders. Make sure piston in cylinder is at TDC on the valve spring that is being removed.
11. Remove spark plug adapter tool.
12. Install rocker arm and pedestal assemblies and tighten screws to 40 Nm (30 ft. lbs.).
13. Install engine valve covers tighten screws to 11 Nm (95 in. lbs.).
14. Install spark plugs and secondary ignition wires.