Giulia Tech Community|
Valve Clearance check and adjustment (Check every 15,000 – 30,000 miles) |
 |
Usually valve trains do not need to be adjusted unless symptoms occur. The easiest way to tell if an adjustment is needed is by listening to the valve train for excessive noise. However, sometimes valves do get tight, if this is the case no sound will occur. If overly tight the valves may not close completely and serious damage can result. Before you begin, the clearance MUST be checked and adjusted while the engine is cold. This is because as the engine heats up the valves and other components expand changing the adjustment gap. The goal of a good valve adjustment is to have this gap completely taken up while the engine is at normal operating temperature.
|
|
Start by pulling the spark plugs. Make sure you keep them in order so you can put them back in the same cylinder they were taken from. After this remove the valve cover noting the bolt lengths and place they were removed. Once this is done remove the top timing belt cover.
|
 |
 |
Use a wrench to turn the crank shaft in its normal operating direction ( CCW on a D series Honda) until both the white TDC make (left) and the UP mark (right) on the cam sprocket are in the 12 o'clock position. For every single rotation of the rank the cam turns 180 degrees so you may need to turn the crank over more then once to line them both up.
|
 |
 |
With the cam shaft in this position you can check the clearance of the valves on the #1 cylinder. Start with the intake side. Use the correct size of feeler gauge and gently slide it between the valve stem and the rocker arm (or cam lob and rocker on a DOHC). When selecting the proper feeler to use, most manufacturers present a range, 0.007 – 0.009 intake, and 0.009 – 0.011 exhaust for this engine. I like to use the smaller of the two however this means it has to be more exact when finalizing the adjustment.
|
|
There should be a slight pull on the gauge when you withdraw it. If there is no pull the valve is to tight. If there is heavy pull or you can not insert the feller gauge at all the valve is too tight. Loosen the adjustment retaining nut and use a screw driver to adjust the valve until it is correct. Leave the screwdriver in place when you tighten the adjustment retaining nut. There is no 'real' torque specs for these but they do not have to be overly tight, a small wrench will work fine. After adjusting, recheck the valve. Adjust the exhaust side in the same way. Do this for each cylinder in the order below.
|
|
UP MARK 12 O'Clock (cam sprocket) Rotate the cam shaft 90 degrees (crank 180). The UP mark is now in the 9 O'Clock position. Rotate the cam shaft 90 degrees (crank 180). The UP mark will now be straight down. Rotate the cam shaft 90 degrees (crank 180). The UP mark will not be at the 3 O'Clock position. |
 |
Once all clearances have been checked and adjustments needed. I like to run out the threads in the valve cover bolt holes. This is not necessary however these are very delicate and do strip easy. By running a tap down through the threads it will make sure they are clean of debris.
|
 |
|
Install the timing belt cover and then valve cover. When tightening down the valve cover on most cars not much torque is needed. Tighten them fairly tight with a small socket wrench. The bolts have a ridge at the bottom so tightening them more does no tighten the valve cover more. Reinstall the spark plugs in the proper order followed by the wires.
|