Service Procedure

Valve Arrangement

FRONT TO REAR

4-90/1.5L ...............I-E-E-I-I-E-E-I

Valves, Adjust

Valve clearances should be checked and, if necessary, adjusted every 15,000 miles. Jet valves must be adjusted prior to adjusting intake valves as outlined below. Adjust intake valve clearance to .006 inch, and exhaust and jet valve clearances to .010 inch.
1. With engine at normal operating temperature, remove rocker cover.
2. Disconnect high tension lead from ignition coil.
3. Position No. 1 piston at TDC compression stroke, then back off intake valve adjusting screws of No. 1 and 2 cylinders approximately 2 turns.
4. With engine in this firing position, adjust the following valves:
a. No. 1 and 2 jet and intake valves and No. 1 and 3 exhaust valves.
b. To adjust valves, loosen adjusting screws, then turn screws until specified feeler gauge can be positioned between valve stem and screw.
c. While holding adjusting screw in position, tighten locknut.
5. Rotate engine 360° to place No. 4 piston at TDC compression stroke, then back off intake valve adjusting screws of No. 3 and 4 cylinders approximately 2 turns.
6. With engine in this firing position, adjust No. 3 and 4 jet and intake valves and No. 2 and 4 exhaust valves as outlined above.
7. After adjustment is completed, install rocker arm cover and reconnect ignition coil high tension lead.