Honda B20A Valve Clearance Adjustment

Hi All,

If you hear some knocking from valve cover, 
most probably the valve clearance needs re-adjustment as the gap is increase due to wear and tear.
Using good lubricant oil will prevent the gap from increasing.
In Malaysia, i recommend JTX1000 as it has EP/AW Extreme Pressure / Anti-Wear.
JTX1000 really can save a lot of money due to engine protection and less maintenance.
Buy JTX1000 before you buy new vehicle.

Feeler gauge brand King Toyo model KT-FG25M.
For easier process, take out the necessary blade.
For this B20A Honda Engine, you can refer to photo.
0.08-0.09 for intake
0.16 (0.10+0.06)-0.17(0.10+0.07) for exhaust.
For exhaust, the feeler gauge doesn't have the 0.16-0.17.
So i add up 2 blades to make gauge blade.

Remove the necessary and valve cover.

I recommend the timing belt shall be cover with paper or any clean material.
Protect it from any oil.


Turn steering to the left.
Use socket bolt sized 17 to turn the crankshaft.
Turn Anti-Clockwise to get the each cylinder on top position.
No ClockWise Turn as it will stretch the timing belt.

Some short note for guide.
Avoid any mistake and finest adjustment.

I used ratchet to loosen as old sludge jammed the thread.

Easy to adjust compared to H22A.
H22A needs some special tool.
Loosen the nut and adjust the center screw.

For this example(intake valve), adjust until the 0.08 feeler gauge blade can slightly move in and out.
Make sure 0.09 is unable to move in between.

You have total 16 valves clearance to adjust.
Slow and accurate will be worth it.

Good Luck!

Some videos.. before and after adjustment...

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