Valve clearance on my Honda Civic engine needed checking so as per the Honda manual, I went ahead to do this critical piece of work.
Safety first as always. Handbrake up, the transmission in neutral, the steering turned fully to the left. There is no need to remove the left front wheel.
The tools used are;
1/2in drive Ratchet with 2 extensions
Feeler gauge set (0.007, 0.009, 0.0011 inch)
High temperature gasket maker safe for gasoline engines
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Step 1: Remove the Valve Cover.
This cover is held by 5 bolts and was easy enough to remove after removing the spark plug wires. I put aside the cover and bolts.
Step 2: Remove the Power Steering Pump and Timing Belt Upper Cover.
The pump and cover has to come off since the camshaft pulley must be visible in order to bring each cylinder piston to Top Dead Centre (TDC).
The pump is held by two 12mm bolts. The belt cover is held by two 10mm bolts.
With the belt exposed, it is a good opportunity to inspect the belt during the job as it is moved.
Step 3: Turn the Crankshaft Pulley.
The first step is the get the crankshaft pulley turned anti clockwise so the UP mark and TDC marks are in the correct position for cylinder 1. A 17mm socket with a 1/2inch extension with ratchet is what I used to turn the pulley.
To access the pulley nut, there is a maintenance hole built into the plastic guard under the engine.
As per the Honda Manual's instructions, get each cylinder to TDC to check/adjust valve clearances. The torque needed to turn the engine was surprisingly small. No Ratchet extension needed!
Step 4: Check, Adjust and Re-check the Valve Clearances.
Using the appropriate feeler gauges, I started with the intake valves:
0.007in will give a little drag.
0.009in cannot fit.
I used a 10mm spanner to slacken the holding nut and a flat blade screwdriver to turn the screw slightly. Once I had the correct drag on the 0.008in, I held the screw with the screwdriver and tightened the nut carefully. I re-checked the drag and once unchanged, I torqued the nut and checked the drag again.
For the exhaust valves:
0.009in will give a little drag.
0.0011in cannot fit.
Same procedure as the exhaust valves.
When cylinder 1 was completed, I rotated the crankshaft pulley 180degrees anticlockwise to get the camshaft pulley into the correct position (actually a quarter turn anticlockwise) for the next cylinder. This is a repetition for each cylinder.
I held each Feeler gauge by its side and carefully inserted it a few times into the valve clearance. The bigger or no go Feeler gauge size would only slightly fit it's head into the clearance but it cannot go in. It's important to not force the Feeler Guage into the clearances.
I used my handy under car roller which transforms into a chair. Being comfortable during this step is recommended.
It is mission critical to recheck with the feeler gauges each time the nut is tightened.
I tripled checked each valve. Once completed I rotated the Crankshaft again and brought each cylinder to TDC, again checking each valve clearance.
Step 5: Re-Installing the Timing Belt Cover, Valve Cover and Spark Plug Wires.
As per the manual, I tightened the bolts in sequence. Since these are 10mm hex head bolts it is critical not to over tighten as they will shear off (yup I know from personal experience with 10mm head bolts).
The spark plug wires and accelerator cad were easy to reinstall.
Step 6: Starting the Engine and Verifying Operation.
Cranking the engine after the job was done verified proper operation of the engine. Vibrations were less at idle. Turning the air conditioning on at idle didn't have the engine making even more vibration and noise.
I intend to perform this valve clearance inspection once a year from now on. I am very pleased with this job!