View Full Version : DIY: Valve adjustment guide

04-18-2008, 10:56 AM
DIY Valve Adjustment for k20a3

-Alex Foshee (If doing this- PRINT THE TEXT OUT AND THE CHART PIC) and read over it before hand. Get the idea of the gameplan together in your head so you know what the job will look like. You will be glad that you did.)

For those who have hondata and see revs upwards of 7700 rpm, I suggest at least keeping an eye on your valve clearances. Adjusting the valves is NOT for somebody who has no knowledge of how the combustion engine works. This write up is very long and detailed because it reflects just how much detail must go into the labor you provide. This is a very long and DELICATE process which will take huge amounts of PATIENCE. If you have neither, I suggest taking it to a mechanic. It took me three tries at adjusting them to get the clearances just right, but now that I know what to look for (particularly,determining whether the friction was just right with the feelers- which will DEFINITELY be explained below) getting the job done accurately will not be a problem in the future and will save me large amounts of money. Once you have done it right, you can do it a million times. If you feel confident then it can be done.

All of the specs shown in this guide are per the Honda Civic Si service manual. I will post pictures as well, since this is a step-by-step diy. Also, I will mention a lot of little tricks that I came about in getting the best results. I went about doing the procedure a few different ways and found the results below to be not only the most convenient, but also more accurate. With that said, on to the supplies.

- 3/8'' drive tq wrench capable from 7ft lb up to 14 ft lb. <--- HUGE. If you don't have this, do NOT attempt this diy. (I bought a generic $20 special from autozone and it worked perfectly. GET A CLICKER TYPE. Sears sells them for $65, but the whole point was to save $$$. =])
- 10mm deep socket
- Thin tipped flat head screwdriver. One that is a smidge longer than the deep socket if possible.
- 6'' ratchet extension
- 3'' ratchet extension (makes the exhaust side nuts easier to tighten)
- 5/8'' spark plug socket
- Set of Feeler gauges (.008 .009 .012 .013 to be used from the pack) ($8ish-sears)
- One pair of pliers
- 1 Tube of Anti-Seize lubricant (for the spark plugs/ at any parts store)
- 1 Tube of Hondabond liquid gasket from the dealership. ($15ish)
- Some will say another new valve cover gasket, but it is NOT necessary as long as you don't somehow knife up the current one. I've reused mine all 3 times with no leaking. You will notice the hondabond is only applied on the corners so it won't be an issue cleaning it off. (If you want one anyway, you can pick one up from either www.inlinefour.com or www.hondaautomotiveparts.com)
- A good pump jack + 1 jack stand. Having a pump jack is very essential as you will be jacking up and lowering the car several times when working the exhaust side. Do not rely on the factory scissor jack as it will take forever.


- Remove the i-VTEC intake manifold cover. (2 bolts, 10 mm)

- Remove the Black plastic spark plug cover. (4 nuts, 10mm)

- Remove the last two screws from the remaining ignition coil packs. (2 screws, 10mm)

- Pull up the coil packs halfway, one at a time, and unclip all of them from the harness by hand.

- Fully remove the coil packs from the engine and set them aside in order of removal. (It's suggested they are installed in reverse order of removal. Reminder at end of diy.)

At this point you should be looking at your valve cover with four holes in the top and a bare intake manifold. Not much more to removal.

- Take pliers and apply pressure to the clamps in order to remove the intake hose from the right side of the valve cover. It can be pushed to the side. No need for full removal.

Note: If working alone, it may be a good idea to zip tie the a/c hose closer to the passenger headlight to help keep it out of the way from the valve cover. (I roped it using the holes above the headlight.)

- Remove the spark plugs using the ratchet, 6'' extension, and the 5/8 spark plug socket. Be sure to keep the plugs in order of where they came from. Probably not necessary, but I'm superstitious about putting stuff back as it was.

Note: The reason for removing the spark plugs is to take the compression out of the chambers. This will make turning the rim/wheel to set the pistons in position MUCH easier, although it can be done without removing them with added muscle. You will be turning the engine over ALOT for consistency and double/triple checks, so it's easier to just remove the plugs.
*It is time to remove the valve cover.

- You should see 6 silver nuts along the edge of the valve cover that are shown in the picture above. (3 up front, 2 above the header, and 1 next to the coil packs.) Remove these and no not lose them. The metal retainers/rubber washers under the nuts can be removed by hand as well. You do not want to lose these.

- To break loose the seal on the valve cover you will probably have to shake it with your body weight a few times. If it's on really tight, be very gentle and run a very thin tip flat head screwdriver along the edges. There is no need to jam it underneath because you will potentially damage the gasket. This is just to remove and break loose any grime, grit, or hondabond that is holding it on.

- Pull straight up and fully remove the valve cover. The rubber lining gasket may stay in the valve cover's groove, or it could stick to the head. Just expect to not rip up on the cover, and carefully remove it. No hulk needed.

Note: This is what you should be looking at by this point.


NOTE: I will be using a few terms that some may not quite be familiar with. The main one and most important is TDC. This means Top Dead Center. At this point, according to the arrows/marks on the cam gears you can determine which piston is at tdc, or sitting at the top of the block.

Looking at the engine from the front of the car, the pistons are labeled 1,2,3,4 respectively from left to right. (passenger to driver)

- Put the car in fourth gear.

- Jack up the passenger side front, leaving the driver side front wheel still on the ground. Insert the jackstand underneath the passenger side front tow hook. Having the wheel off the ground is going to allow you to crank over the engine while watching the cam gears. (You will just kneel down and turn the tire with your hands while you watch the cams spin into place. It's really simple.)


- Set the #1 piston to TDC by turning the wheel clockwise until the marks are shown like the pic below.

The arrow on the intake vtc gear is just at 12 o'clock. You will notice that two corresponding hash marks will be facing each other
at 3 o'clock (exhaust) and 9 o'clock (intake/vtc) respectively. With this done, the #1 piston's valves are ready to be adjusted.

The piston's valves will be adjusted in the order of ****1,3,4,2****!
This is VERY important. Follow the chart below.

04-18-2008, 10:57 AM
Note: The easiest way to determine when the piston is exactly at top dead center is by watching the cam lobes. When the intake lobes and exhaust lobes are pointing inwards at each other (intake slightly upward angle) over the certain piston you are fixing to work with, then THAT and only THAT piston is at TDC. Having the cam gears set to duplicate the proper 90 degree angles (12,3,6,9 oclock) will prove this.

- To get a feel for things, turn the gears to #1 TDC on the chart above. Then look at the cam lobes over piston #1. They will be pointing toward each other. Then put the gears to #3 TDC and check the cam lobes over piston #3. They will look exactly as they did previously on piston 1. Easy as pie. Set everything back to piston #1 and lets get started.


Note: Do not even bother thinking about the exhaust side for now. The procedure I'm typing calls for exacting the clearances across all of the intake side first, and then across the exhaust side secondly.

DO NOT set the feeler gauges up on the plastic underneath the windshield. They can easily fall down and possibly fall into the engine. HUGE precaution. Just a heads up.


- Take every feeler gauge anywhere from .005-.012 and begin trying to slide them inbetween the top of the valve's stem (from the #1 piston which you just set at TDC) and the bottom part of the rocker arm.

Note: Best way to go about this is from the smallest up. Start at .005 and if it goes in, then try it with .006. Eventually, the next size will NOT fit at all. When that happens, you know that the valve's clearance is equal to the last feeler gauge that fit. Example: .006 barely fits through with quite a bit of resistance and friction while sliding, but only the tip of .007 will edge into it. Two pics below show clearly. The valve clearance for that one valve would currently be .006. Some call it the "go/no go method". Good to maybe google for more info.

Best thing to do, is to put the gauge at the very bottom when you can feel it against the actual valve stem. Then slide it upwards along the valve and you will feel it go over the top of the valve. Once again, easy as pie. Take a few minutes and work with this. Once you feel that it's no problem finding the slot for the gauge, then let's do this!


- We are setting all the intake clearances at .008. Depending on what the valve previously measured, you will determine whether to tighten or loosen the small screw that is shown. (will be explained in pic below)

- To properly adjust the screw, you must first loosen the 10mm nut that each intake valve has in plain view.

Note: When you turn the screw with the flat head screwdriver, (after loosening the nut around it) it will be VERY sensitive. What I mean is, moving the screw in either direction by even as little as **3 degrees** it can potentially tighten/open the space by a difference of .001-.002. Be very careful when adjusting the screws because the slightest turn makes a difference.

- Work the left side intake valve and set it at .008 where it fits as the pic above shows, and .009 will only go in as far as the pic above shows as well.

- Do the same with the right side intake valve still on piston #1 and get it at .008 just like with the left side. Another side note about tightening the nuts around the adjusting screws.

*****NOTE: Before ANYTHING is tightened read this. All of the nuts on the INTAKE side, (10mm) around the adjusting screws, are to be tightened exactly at 14 ft/lb each. This is essential.

- Take the 10mm deep socket and stick the screwdriver through it. Then line it up and over the nut like shown. This is how you will hand tighten the nuts first. Once the screwdriver is holding the screw in position, hand twist the socket as hard as you can.


Note: This will help keep the screw from moving when you torque it down with the ratchet.

- After hand tightening both of them, double check the clearances for both intake valves on piston #1. They should be the same. (.008 = go. .009 = no go.)

- If everything is still set, it is time to torque them both down. Set the torque wrench to 14 ft lb's and tighten the left one. Triple check the clearance on that valve after it is tightened to 14 ft lb's. If it's still EXACTLY the same, then it is set for good. Do this for the intake valve next to it as well. The intake side of piston #1 is set. =]

- Turn the cams to position piston #3 at TDC as shown in the chart.

- The cam lobes are pointing together now, so lets get to adjusting. Go ahead and do the exact same procedure you just did with piston #1. Re-read and refollow the directions stated above. After both piston #3 intake valves are set at .008, then it's time to head back to the tire and turn the gears to "Piston #4 at TDC as shown once again in the chart.
- The lobes over piston #4 are facing each other now and do the same procedure you did with pistons #1 and #3. Things should be going a bit quicker since you have already gone through this twice. Routine is good.

Note: You will notice that rubber hose (annoyance) will kind of be in the way. Just pull it back and hold it towards the intake manifold to get your hands in there. No need to remove it, but some left and right hand coordination helps here.

Intake valves at piston #4 are now set at .008 so we can jump back at the gears and set them at "Piston #2 at TDC".

-Do the usual with the intake valves at piston #2. Set both at .008 and make sure the clearances are exact. Don't forget to double and triple check after tightening. Once done with piston #2, and all nuts are tightened to 14 ft/lb's and clearances are exact at .008, then the intake side is finally done!!! Halfway there!

NOTE: There is a modification to be made to the exhaust side feeler gauges to make the job go easier on the other side of the engine. The engine itself sits at quite an angle in the bay so this is where the jack comes in handy. The mod to the gauge will allow give it more of a custom fit to slide past the edge of the engine head. Mod described below.

If you have a bench vice this makes things much easier. You will be making an extra bend near the tip of the feeler gauge. I recommend bending a larger gauge (.016 or something/random) because they are easy to snap. Take a few minutes to get a crease with a vice/pliers then bend it with your thumb. DO NOT continue to bend it with the tools. It will break. Trust me. Apply the extra bend to .012 and .013 for setting and checking.

- With the #1 piston set at TDC, lower the car back on the ground. You will not need the jack anymore from this point on- only the jack. The reason for lowering the car is to make it easier to lean to the back of the engine. You may notice that after about 5-10 minutes the backs of your knees will hurt. The lower the car, the better.

NOTE: The exhaust side is exactly like the intake with one exception. The exhaust cam only has one lobe which means there is only 1 rocker arm as opposed to 2 on the intake side. What this means is that when doing the same procedure to the exhaust side, you must do both at the same time instead of going left-setting, then right side- setting. Following steps will help out.

- Look back at the exhaust side and you will see 8 more nuts around 8 more adjusting screws across the board just like the intake side. (all 10 mm)

- Take .010-.015 and start figuring out whether or not the screws should be tightened or loosened just like with the intake side.

NOTE: If you have the gauges bent like shown above, it will allow a better angle at not sliding the gauge in, but out. Without it, you will be able to get it in, but when pulling the gauge out, it will hit the inside lip of the head. This is the reasoning for the extra bends with .012 and .013.

- Loosen both nuts on the piston #1 exhaust side rocker arm after figuring which way both screws are going. (tighten/loosen)

- Set the left side clearance at .012 (go)/.013(no go)

- Hand tighten both nuts before torqing anything down. Use the deep socket 10mm and flat head screwdriver to hand tighten both.

- Recheck the clearances and make sure they are exact.

04-18-2008, 11:02 AM
NOTE: THE EXHAUST NUTS WILL ONLY BE TIGHTENED TO 10 FT/LB's! Make sure to change the setting on the torque wrench so that they do not get over tightened.

- If they are set at.012, then go ahead and torque the nuts down to ****10 ft/lb's****

- Triple check the clearances after torqing to 10ft/lbs and make adjustments where necessary.

- Once piston #1 is set on the exhaust side, then jack the car up just enough where the tire is off the ground and can be turned like before. Turn the cams to "Piston #3 at TDC". Lower the car.

- Repeat the above process on the third piston using same side tightening techniques and only torqing the nuts to 10 ft/lbs. .012 (go)/.013(no go)

- Jack the car back up and position the cams to "Piston #4 at TDC." Lower the car.


- Repeat the above process on the fourth piston using same side tightening techniques and only torqing the nuts to 10 ft/lbs. .012 (go)/.013(no go)

- Jack the car back up and position the cams to "Piston #2 at TDC." Lower the car.

- Repeat the above process on the second piston using same side tightening techniques and only torqing the nuts to 10 ft/lbs. .012 (go)/.013(no go)

The valves are now all adjusted. Time to put the cover and accessories back together.

- Take the spark plugs and put a thin line of anti-seize lubricant along one side of the threads. Use the spark plug socket and 6'' extension and tighten the spark plugs to ***13 ft/lb's.*** Remember to try and keep the same plug in the cylinder that it was removed from.

- Clean off any hondabond along the corners of the valve cover gasket as well as any oil that still may be on it- or replace with new gasket.

NOTE: Best way to apply hondabond is to dab it along the gasket. Otherwise the goo will streak and not be as effective. Dab it like icing a cake.

- Apply hondabond only along the four corners of the engine by dabbing just a little all along the corner. It is stated by the manual to only do the corners. As long as the mating surface along the head and gasket are clean and hondabond is on the edges, then it will not leak. Trust me.

- Replace valve cover onto engine carefully and push straight down on the top. You will feel the cover snug down as the rubber seals move around the spark plug columns.

- Wipe off the 6 retainers rubber washers that go around the head studs. The rubber washer that goes next to the coil packs (#4 in the pic below is different than the others. It will have a gap in it. Compare it to the others. It's easy to find. Tighten valve cover nuts at only 7 ft/lb's and in the sequence shown below. The studs can bread very easily so only go 7ft/lbs and if the washer starts spinning, move on to the next nut.

- Insert the Coil packs halfway and clip then back up with the harnesses that run to the ignition then proceed to push them snugly over the spark plugs in reverse order of which they were removed. So if you removed from left to right, then install from right to left. They are already clipped in the pic above. The four screws that hold them in are stated at 10 ft/lb's each.

- Put the black plastic spark plug cover on and tighten the four nuts at 10 ft/lbs each.

-Reconnect the breather hose to the intake and valve cover.

You are FINALLY done.

04-18-2008, 08:09 PM
damn, did you have it saved or something? nice write-up and very thorough

04-18-2008, 08:27 PM
It took me a long time to make this. I definitely had it saved.

04-20-2008, 02:37 PM
nice job when should u do it after how many miles ?

04-21-2008, 09:48 AM
It took me a long time to make this. I definitely had it saved.Glad you did (as did I) I'll delete my duplicate copy of the thread I posted.

04-22-2008, 02:58 PM
So how much would this cost to get done "ballpark figure"? Im at 90k and I dont want to overpay to much. This is way to delicate of a job for me,lol:bolt:

04-22-2008, 08:58 PM
nice job when should u do it after how many miles ?

I did mine for the first time just past 75k and found large gaps between my valves. I notice a big difference in how smooth my acceleration was after I did it.

04-22-2008, 09:26 PM
thanks for posting the awesome writeup!!! it hit some finer points i was wondering about, havnt done this before on the k series but was planning on it this weekend!!!

So how much would this cost to get done "ballpark figure"? Im at 90k and I dont want to overpay to much. This is way to delicate of a job for me,lol:bolt:

its not hard, go to craftsman and buy some feeler gauges its 10 bucks...learn to do this, its one of hte best things to know how to do on a car...man up and do it

04-22-2008, 11:24 PM
damn, did you have it saved or something? nice write-up and very thorough

yezzir, INDEED!

Canuck Civic
04-24-2008, 03:35 PM
Is this a good idea to do at 75,000 km

04-25-2008, 07:27 AM
I'm at 82K and I really need to do this...

04-25-2008, 07:47 AM
Damn good write up man. Nice job.

04-25-2008, 08:13 AM
Very detailed write up. Great job, very informative.

04-27-2008, 09:38 PM
did this yesterday, took about 2 hours, noticed a difference, smoother acceleration and less valve chatter...plus it was a good opportunity for me to put my new VC gasket in...YAY!!

04-29-2008, 10:45 PM
you said you noticed gaps when you took it apart and did the adjustment. how bad was your car running before you did the adjustment? I am at 88k and i feel like i am losing power. i need to do a full tuneup. Will look over your instructions again. Would like to try and attempt this, but it looks like a lot of work.

04-30-2008, 06:47 AM
you said you noticed gaps when you took it apart and did the adjustment. how bad was your car running before you did the adjustment? I am at 88k and i feel like i am losing power. i need to do a full tuneup. Will look over your instructions again. Would like to try and attempt this, but it looks like a lot of work.

its not that much work at all...seriously...but if you've never used feeler gauges or adjusted valves before, it might take a little longer...you probably have other things to deal with, this shouldnt do too much to make it feel more powerful, it will make it run smoother and quieter (valve chatter wise)

06-28-2014, 02:50 PM
According to the user's profile, they're still active, so..... 6 yr bump for pics!