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K20A3 Valve Clearance Adjustment

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20
***** Originally Posted on www.ephatch.com *****

**Please note, the specs used below are for the K20A3. (USDM engine in the Si)**

I did this following the instructions in the service manual (http://www.ephatch.com/forum/showthread.php?t=44979).

1. Make sure your engine bay is pretty clean; you don't want to drop any dirt or sand into the engine. The cylinder head also MUST BE COOL (under 100 F or 38 C).

2. Jack and support the front end of your car and remove the passenger side front tire. (MIGHT BE OPTIONAL STEP DEPENDING ON DROP... SEE STEP #8 to see why)

3. Remove the intake manifold cover: 2 bolts
valve01.jpg


4. Remove the cover over the ignition coils; be careful not to drop the spacers under the two outside bolts. Underneath, there will be two ignition coils still bolted on; remove those two bolts.
valve02.jpg


5. Remove the breather hose (I'm pointing to it below). I had to remove my air box cover to get the breather hose off (the ratchet is on one of the ignition coil bolts).
valve03.jpg


6. Remove the ignition coils. Pull up and loosen them, then you can twist the coil so you have enough grip on the release clip to remove the wire harness. (Sorry about the blurry pic)
valve04.jpg
]

7. Remove the six cap nuts holding the valve cover on. I also removed the washers to make it easier to pull off. Remove your dipstick, too.
valve05.jpg


The valve cover should lift off with a little bit of tugging. If you have a spare pair of hands around, it might help to keep hoses and your throttle cable out of the way. Now, inspect your cams for gauling. None here!
valve06.jpg


8. Use a 19mm socket and long extension (you may need to use more than one extension) to turn the crank shaft. I used my 25" breaker bar instead of a ratchet to turn the crank, and it was very easy.
valve07.jpg


Turn the crank until the arrow on the VTC actuator is up, the punch mark on the exhaust camshaft sprocket is up, and then align the two marks on each sprocket so they match up. This give you top dead centre (TDC) for cylinder one (passenger side).
valve08.jpg


9. Here are the gauges I used for the intake side. The specification for the gap is 0.008 to 0.010 inches. Notice I have one in the middle, too. The exhaust gap should be from 0.011 to 0.013 inches. DON'T TAKE MY WORD FOR IT; MAKE SURE YOU HAVE THE RIGHT ONES.
valve09.jpg


10. I put a bend in each of the gauges I intended to use to make it easier to fit them in between the valve stem and adjusting screw. There should be some drag on the gauge when you slide it back and forth. You should NOT be able to get the next gauge up in the gap (ie the 0.011" on the intake side).
valve10.jpg


11. If you do need to adjust the gap, I suggest using the .010 or .009 in the gap while you use a 10mm wrench to loosen the lock nut and a slot screwdriver to turn the adjuster. If you make if just snug enough on the larger gauge so you can still pull it out, it should be just right when you check the gap again.

This step requires a light touch. Loosen the lock nut with the wrench, then GENTLY turn the screwdriver a bit each way. You will be able to feel the adjuster connecting with your gauge. If you haven't done this before, take your time getting a feel for the right amount of tension on the adjuster screw that gives you the right gap.

Tighten the lock nut, then CHECK THE GAP AGAIN.
valve11.jpg


12. Check and adjust exhaust side, cylinder 1.
13. Rotate the crank 180 degrees clockwise (camshaft pulley rotates 90 degrees) and check CYLINDER THREE clearances.
14. Rotate crank 180 degrees clockwise and check cylinder FOUR.
15. Rotate crank 180 degrees clockwise and check cylinder TWO.

16. Install the valve cover in the reverse order that you took it apart. CHECK THE MANUAL for the order you need to tighten the bolts. I suggest using a torque wrench; many people have broken these in the past. You tighten them in 2 or 3 steps, in the right order (shown in the manual).

I bought a new gasket THAT DID NOT FIT, thanks Honda. You also need some gasket maker.
valve13.jpg


Clean the old gasket material where it is left on the engine, and apply the liquid gasket to the following spots (copy the spots from the old gasket if you can).
valve15.jpg

valve16.jpg

valve17.jpg


Don't forget to re-install the passenger side wheel before you drive away. Remember you are supposed to re-check the torque on your lug nuts after driving a little bit.
 
Any ideas if this is the same spec and figures for the uk k20a2, uk spec type r? As I'll give my own a whirl if this is all it needs ?
 
I'm hopefully going to do this soon. Looked at the maintenance manual and in the type r section from 02, the inlet clearances are the same but the exhaust clearances are 0.25 - 0.29mm or 0.010 - 0.011 inches. This is what the actual manual I got for the car says so, best to have someone double check that, but least its a guide to what the clearances have to be.
 
Sorry for reviving this thread again but does anybody know if this is the same method for the K20Z4? (FN2)

I'm assuming it's pretty much the same (although the clearances may be slightly different).

Thanks
 
Sorry for reviving this thread again but what ddi he mean here:

"be careful not to drop the spacers under the two outside bolts"

What spacer is?

Sorry my english!
 


Hi, I was wondering if you could clarify something for me http://type-r-owners.co.uk/forums/showthread.php?77522-valve-clearances. This article looks like a Honda official document. In part six it says rotatethe crankshaft counter clockwise which turns the cam pulleys 90 degrees anticlockwise, and then adjust valves for piston number three. Surely this is wrongas the firing order in reverse would be 1-2-4-3 rather than 1-3-4-2 in aclockwise direction. The article http://www.vtec.net/articles/view-article?article_id=143824&page_number=3 seems to be right. The first time I didthe valve clearances I followed the first procedure and the engine soundedawful as cylinders 2 and 3 were well out. When I did the valve clearance againI checked the cam positions were pointing inwards for the cylinder concernedand after adjusting the clearances the engine now sounds perfect. Thanks Dave.





 
The first thread is UK and a H22 engine. The 2nd thread is not and where he mentions the cars firing sequence of passenger to driver, it's reversed for us as their drivers side is our passengers side.
 
I am going to be attempting checking and adjusting my Valve Clearances today on my K20A2 EP3 as i am on 110,000miles.

I am right in saying the intake should be between 0.08-0.10 and exhaust 0.10-0.11 and the firing order of the engine is 1-3-4-2?
 
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