22R Valve Adjustment
22R Valve Adjustment
Written By Eric Stegall March 2000
After putting 150,000 miles my 1981 22R motor, I decided it was time for some much needed maintenance. I did the usual things like changing the timing chain, water pump, fuel pump, cap, rotor, plugs and wires. While I was doing the timing chain, I decided to get the head rebuilt. After I got everything back together, I found it necessary to readjust the valves.
|Remove air cleaner and valve cover|
If they are too tight, you run the risk of burning the exhaust valve seats and the valves might not close all the way. Whether they are too loose or too tight, your motor's performance will suffer.
|Pulley notch at "0" degrees|
I drove the truck up and down the expressway a few times to bring the engine up to normal operating temperatures. I pulled it into the garage, applied the parking brake, shifted the transmission into neutral and turned the engine off. To gain access to the rocker arms, I removed the air cleaner assembly, set aside any hoses and wires attached to the valve cover, and removed the valve cover.
|#1 intake and exhaust rockers are loose enough to slide sideways|
When the number 1 piston is at TDC and on the compression stroke, both of the intake and exhaust rocker arms should be loose (in the picture I am actually able to slide rocker arms off the cam lobe - this is loose).
If they are not both loose, you must rotate the crankshaft bolt 360 degrees since you are not on the compression stroke.
|Adjust indicated valves (arrows)|
Adjust number 1 and 2 intake valves and number 1 and 3 exhaust valves to the indicated specs. To do this, I loosen the lock nut, insert the proper feeler gauge between the rocker arm pad and the valve stem.
Turn the adjusting screw with a screwdriver until there is a slight amount of resistance or drag on the feeler gauge. Hold that setting with the screwdriver and tighten the lock nut. Slide the feeler gauge out and make sure there is still a slight drag to it. If not, repeat the above step.
|Setting valve clearance|
The number 1 piston is NOT on the compression stroke. Now I adjust the number 3 and 4 intake valves and number 2 and 4 exhaust valves to the indicated specs. I reinstall the the valve cover, the hoses, and the air cleaner assembly and I am all done.
|Adjust remaining valves (arrows)|