DIY Valve Adjustment

Before you begin this task, leave yourself enough time to be able to do this job carefully and accurately without having to rush it. You will need a couple of hours to do this the first time you attempt it.

Conditions    Do not attempt this procedure on a blustery day. Wind with sweep up dust into the top of the engine whilst you are working on the car. If you can do this procedure in a garage, all the better.

Tools            Feeler gauges, Trolley jack, torque wrench, flat headed screwdriver, valve adjustment tool (see tips and tricks), socket set with at least a 19mm socket with extension, 10mm socket, pliers.

Preparation    Only start this procedure when the car has been left overnight, so that everything is cool. Then the correct tolerances are achieved. 

Step 1.    Remove PCV valve from cam cover by pulling the fitting out. 

Step 2.    Remove breather hose from cam cover by using pliers to squeeze the cir-clip together to release the hose.

Step 3.    Remove earthing wire mounted on front of engine. 10mm socket required.

Step 4.    Remove power steering hose mount from cam cover. 10mm socket required.

Step 5.    Undo one end of the wiring harness from the alternator using a 10mm ring spanner. First pull back the rubber shroud protector to reveal the 10mm nut.

Step 6.    Undo the 10mm bolt securing the plastic wiring harness over the cam cover.

Step 7.    Remove the wiring harness from the cam cover.

Step 8.    Remove the spark plug cover.

Step 9.    Remove all 4 spark plugs. (Reduced compression when turning engine over by hand)

Step 10.    Carefully remove all 8 10mm cap nuts from cam cover, including washers. Collect them up to prevent loosing them.

Step 11.    Crack loose the wheel nuts on the front left hand side of the car. Jack up the car and remove the left front wheel using the trolley jack on the side jacking point. Place a wheel chock under the front rear wheel to stop the car from moving.

Step 12.    Carefully remove the cam cover. Do not pry it off with a screwdriver. Use the breather mount and oil filler to tug on. You should see something like in the picture below. The red arrows show you where the feeler gauges need to be positioned to measure the clearances between the cam lobe and the rocker arm follower.

Step 13.    You now need a 19mm socket with extension to thread through the access hole in the wheel arch, to mount onto the crankshaft pulley. You will turn this with the socket ANTI-CLOCKWISE ONLY!!! If you turn this clockwise you run a BIG risk of the cam belt jumping a tooth on the pulleys.

Step 14.    You now need to turn the engine over to get the No. 1 piston to TDC. The UP or arrow marks on the pulleys should be at the top, and the TDC grooves on the edge or side of the pulley should align with the cylinder head surface. The distributor rotor should be pointing towards the No. 1 spark plug wire. See illustrations.

Step 15.    Check the clearance on all the valves for the cylinder No. 1 with a feeler gauge. The gauge should pass the gap with slight drag.

Step 16.    If the gauge passed with no drag or cannot be inserted, adjust as follows;-

a. Loosen the adjusting screw locknut.

b. Turn the adjusting screw to obtain the proper clearance.

c. Hold the adjusting screw in position and tighten the locknut. Correct locknut torque is 20 ft lbs(27Nm) on models without VTEC and 14 ft lbs(20Nm) on models  with VTEC.

Step 17.    After the locknut is tightened, recheck the clearance and readjust as necessary.

Step 18.    Rotate the crankshaft 180 degrees counterclockwise ( the cam pulley will turn 90 degrees ). The UP or arrow marks should be at the exhaust side. The distributor rotor should point to the number three spark plug wire. At this point the valves on No. 3 cylinder can be checked. Repeat the adjusting steps previously described as necessary.

Step 19.    Rotate the crankshaft 180 degrees counterclockwise ( the cam pulley will turn 90 degrees ) to bring the No. 4 cylinder to TDC. Both UP or arrow marks should be at the bottom and the distributor rotor should point to the number four spark plug wire. The grooves on the pulley align with the cylinder head surface and with each other. At this point the valves on No. 4 cylinder can be checked. Repeat the adjusting steps previously described as necessary.

Step 20.    Rotate the crankshaft 180 degrees counterclockwise ( the cam pulley will turn 90 degrees ) to bring the No. 2 cylinder to TDC. Both UP or arrow marks should be at the intake side and the distributor rotor should point to the number two spark plug wire.  At this point the valves on No. 2 cylinder can be checked. Repeat the adjusting steps previously described as necessary.

Step 21.    Once all the valves have been adjusted and rechecked, reinstall the valve cover on the engine. Reinstall the distributor cap (if you removed it). Start the engine and check for oil leaks.