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How to adjust H22 valve clearance

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Merlin
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How to adjust H22 valve clearance

Post by Merlin » Wed Jan 09, 2013 4:39 pm

Written by drlinkin

Detailed below is a simple guide for valve clearance/lash adjustment on h22 (JDM or UKDM) engines. The basic principle applies to all engines with non hydraulically adjusted valves and only requires a minimal amount of skill and knowledge; plus of course the confidence to take your engine to pieces!

Things needed:

•A stone cold engine

•Carburettor/Choke cleaner

•(For h22 specifically) 0.006”, 0.007” and 0.008” curved end feeler gauges

•Ratchet and 10mm socket

•10mm Spanner

•Either mole grips and a long deep well 10mm socket, or the Honda valve adjustment tool (available from snap-on for an extortionate price or from American Ebay for the imitation – which works just as well for about £30!)

•Flat screwdriver with a long, thin neck but a smallish head.

•19mm Deep well socket and a larger ratchet/breaker bar

•A telescopic magnet (not essential, but may be handy!)

•Patience

•Possibly a good chiropractor

•A cup of tea!

As mentioned before the principle of valve adjustment is roughly the same on all manual adjustment engines. The subtle differences will occur in the location of the locknuts and their size, and of course the actual clearances themselves. The h22, whilst not the most difficult engine I have come across it is one of the most awkward! The combination of the deep recesses for the valves and the cantered engine it is a bit of a pain (mostly on your lower back!) However as a very often neglected service item your can make your engine sound and run a little bit sweeter, for not a lot of time and money.

Anyhow, the procedure:

Step One. The strip down.

Remove your positive battery terminal before you begin. You will be removing live cables from the alternator and you don’t want a short!

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First things first, you need to remove your cam/rocker cover and all the bits that attach to it.

You will need to remove the 4 bolts (circled) that hold the spark plug cover in place and then lift it out of the way.
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Then you can pull the HT leads out and put them to the left hand side of the engine or onto the exhaust manifold (remember the engine MUST be cold before doing the adjustment!)

Then you need to remove the two bolts holding the throttle cable in place (circled above) on the cam cover. Again, you can tuck this further up the back of the engine near the intake manifold (careful not to kink this, it can take small bends, but be gentle)

Next you need to remove the breather pipe between the cam cover and the intake pipe.
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I have an aftermarket one on mine that just pulls off but if you have a standard intake you may find a ‘pinch clip’ or jubilee here.

You also need to remove the PCV valve on the right hand side of the cover at the top. It just pulls out of its rubber housing. Tuck both these items up near the intake manifold.
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Now, you need to tackle the first fiddly job of the day. Looking down the front of the engine and to the right you will see the alternator (circled in blue).
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There should be two rubber covers over the two plugs we need to get to. Begin with the one on the left of the alternator and pull back the cover to expose a large green plug.
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Then push the flat, rectangular clip down on the top and pull the plug free of the alternator.
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Now for the more awkward one: Unless you are blessed with ‘hobbit hands’ this next bit may prove tricky! Pull back the second rubber cover, this time on the front of the alternator and you should see a black wire with a ring connector, which is secured to the alternator with a 10mm nut. However there is conveniently not enough space to get anything but the smallest of ratchets and sockets between this bolt and the fan on the radiator. However with a spanner and some perseverance you should be able to get the nut off, and consequently remove the cable too.

Now, working back up at the cam cover:

Now you need to locate the power steering pipe (pictured below) on the right hand side of the cover and pull it upwards out of its locator, which should then expose a 10mm bolt underneath. Remove this and the pipe ‘U’ locator and put them to one side.
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Remove the 10mm bolt securing an earth ring (pictured below) on the right hand side of the engine, down near the engine mount and tuck the wire and ring out of the way.
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Then remove the 10mm bolt which secures the (now free) alternator wiring cover (pictured in yellow circle below). Lift that away and tuck it to the side, whilst being careful not to pull the wires or bend the cover excessively.
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You should now have full access to the 8 10mm dome nuts (4 shown on top picture, and hidden three shown below that, the furthest left middle nut is not shown in pictures) that hold the cover in place. There are two permanently exposed on the top left and top centre of the cover, and one now exposed (from under the alternator wiring cover) on the top right. Moving downwards you should have two nuts on the middle left and in the centre now exposed by removing the spark plug cover, and a further nut now exposed from the alternator wiring on the middle right. And finally you should have two permanently exposed nuts on the bottom left and bottom right.

Loosen these in a diagonally opposed sequence, starting from the centre and working your way outwards. This will help avoid squashing or pinching the rubber gasket underneath in specific places. Once all the nuts are undone, depending on how long your cover has been in place the cover will either lift off easily or be an absolute ball-ache! However if it’s the latter case do not panic, simply use a rubber mallet or equivalent and gently tap around the sides of the cover to free it up. Then by pulling on the oil filler cap, the left breather pipe spout and other extrusions on the cover you should be able to lift it free, and with any amount of luck, keep the gasket intact too.

*Note: As a precaution, it may be worth checking all the rubber washers under the 8 dome nuts to see if they are secure in the cover. If they aren’t you will lift the cover up and as they are dislodged by the studs the nuts attach to they will fall down the back of the engine and may be lost forever! So either using a magnet or simply your fingers give each one a quick pull and if it’s secure. However if one does come out then keep it to one side for when you re-fit the cover later.

Now the cover is off, take a quick moment to remove the gasket gently from its recess and give it all a clean up. Now if yours is split and broken then don’t bother trying to remove it just leave it in place and get a new one. Work your way around and gently persuade the gasket free. If you managed to get it all out in one piece then using shop towel/cloth and your flat bladed screwdriver work your way around the gasket groove and get all the accumulated crap and oil out. As for the gasket, I found spraying a cloth heavily with carburettor cleaner and wiping the gasket through it worked a treat.

If you want to be really thorough; then give the metal mating surface of the head a clean with shop towel too.

Finally, by turning your wheels fully to the left expose the front part of the N/S wheel arch. And remove a couple of bolts from the engine under tray on the near side (right, if viewed from the front of the car). I haven’t shown the ones on the very bottom of the car but there are two in the arch itself.
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(One is hidden upwards; see where my finger is pointing in the picture below)

You should only need to remove enough bolts to pull the cover down sufficiently to gain access to the crankshaft pulley and bolt.
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If your car is excessively low or your wheels excessively large, you may need to jack the N/S front corner of the car up and maybe remove the wheel to gain access.

Step Two. The adjustment.

H22 valve clearances:

Inlet = 0.006” – 0.007” (cold)
Exhaust = 0.007” – 0.008” (cold)

Valve locknut tightening torque = 20nm / 14lb-ft (not much, really!)

Now, with your cam cover off, and the crankshaft pulleys exposed; you are ready to do your adjustments.
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Begin on cylinder number one. The cylinders are counted in ascending order from the camshaft pulleys to the distributor. So the farthest right one (as viewed from the front of the car) is cylinder one, with number four furthest left next to the dizzy.

You need to put cylinder you are working on in TDC (top dead centre). This is the point at which the piston is at the top of its stroke in the cylinder, and therefore the valves will be shut. To ensure that your engine is at this point, turn your attention to the face of the two camshaft pulleys on the right of the engine. You should be able to see two distinctive marks on each one (don’t worry if you cant, you will do in a moment!)
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You are looking for an arrow pointing outwards on the ‘spoke’ of the gear, and a small, straight notch on the outer lip of the gear. If you cant see all of/any of these marks then it just means your engine has ‘stopped’ on a slightly different part of its rotation, so you now need to manually turn it over.

Put your long reach 19mm socket and ratchet/breaker bar onto the crankshaft pulley bolt.
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**Note, if you are feeling a bit weedy, or can’t get enough clearance to move a bigger bar on the bolt then remove all four spark plugs from the engine and store them in a safe place, this will stop you having to compress your cylinders with each ratchet turn.

As you crank over the engine, you will see that the camshaft pulleys are rotating and the cams are operating the rockers at different intervals. What you are looking for when bringing cylinder one to TDC is the ‘up arrows’ on the pulleys are both pointing directly upwards and the outer lip TDC marks are pointing at each other (see two pulley pictures above with yellow circles). When your pulleys look like this; you now have cylinder one at TDC and are ready to begin adjustment. It’s worth nothing that the marks don’t have to be exact and can be a little ‘before’ or ‘after’ each other, as long as they are close. If you overstep it and the arrows begin going past the ‘upwards’ position then DON’T turn the crankshaft clockwise (as mentioned in a previous paragraph) simply keep cranking the engine anti-clockwise until you can get in the right position again.

***Note, For a bit of reassurance, if you ever want to be exactly sure that you are adjusting the right cylinder then you can, with clean hands/gloves feel the actual cam lobes to make sure they are not depressing the rocker arm, and that the rocker arm is as such; free. Using your thumb and forefinger feel the central, large lobe (the VTEC one) on both the intake and exhaust side of the relevant cylinder that you intend to adjust and make sure it is pointing somewhere upwards, and not down onto the rocker arm. If it is at anywhere in the ‘upper hemisphere’ of rotation then the engine is set to TDC on that cylinder.

Now its time to use your trusty feeler gauges.
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Its worth mentioning that curved head feeler gauges are better suited to the awkward nature of the h22, however if you can only get your hands on a straight set (that you wont have to give back to someone!) then you can very gently ‘pinch’ the end together and make it into a right angle. Ideally you should do the same for a curved head one too, it just makes the job a little easier and more accurate.

Starting at the inlet side, take your (now pinched to a right angle) 0.006” gauge, wipe it clean and then attempt to insert it in the gap between the rocker arm and the tappet face (see picture below).
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If the gauge encounters heavy resistance then your clearance is set too tight for that valve. Try manipulating the gauge into the gap again but don’t force it, it’s just sometimes a bit awkward if your gauge is coming in at a bit of an angle.

If you really can’t get the gauge in, or the gauge ‘falls in’ with no resistance then you need to move to the next level – adjustment.
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For those who could get the 0.006” in and it was loose; then take your 0.007” gauge and see how that fares in the gap. If it begins to drag in the gap then you are probably set somewhere close, and may only need minimal adjustment, if any.

Nevertheless, take your valve adjustment tool (whatever you may be using) and loosen the 10mm locknut of the valve that you wish to adjust. It shouldn’t be too tight.
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****Note, you may find it easier, regardless of which tool you have to remove the tall studs that hold the valve cover in place when working on cylinders 1 and 4.
ImageThey simply unscrew using the 10mm long reach socket. Keep them in a safe place and remember to put them back when you’re finished!

Now, if you couldn’t get the right feeler gauge in:

Either leave your tool in place on the nut or remove it, and then using your small flat blade screw driver turn the central screw about 90 degrees anti-clockwise. Have another attempt with the 0.006” gauge. Can you get it in yet?

If you can, then try the 0.007”. If you leave that in the gap (presuming you can get it in, if not repeat the step above) and turn the screw clockwise it should become trapped between the rocker arm and the tappet. This is about where you want to be, so take note of the orientation of the screw notch. You will need to turn the screw anti clockwise slightly in order to free up the gauge. Then when it is out you can turn the screw back to where it was when the gauge was in.

Now using all the dexterity you have, you need to tighten the locknut whilst using the screwdriver to stop the screw turning with the nut. It is of course, easier with the right tool, but still do-able with a long 10mm socket in mole grips and of course, the screwdriver.

What you are ideally looking for on the inlet side is a mid value. You would ideally like the 0.006” to be just a bit too loose, but still drag a bit, and the 0.007” to be just a bit too tight, and drag a lot. However since valve adjustment and the use of feeler gauges relies completely on the skill and perception of the user you may end up a little tight or a little loose. However it is not the end of the world if you are either.

From my experience, it is better (quieter and smoother running) to be a tiny bit on the loose side of the clearance. When I first did the job on my h22 I went very tight and the valve train noise was a little louder than I would have liked.

For the exhaust side, all the same principles apply except you will have slightly easier access (and a better view!) and you need to use the 0.007” and 0.008” gauges, not involving the 0.006” at all.

Remember: The locknuts don’t need extreme torque when tightening (only 20nm), and rounding one off really would be a nightmare!

After you are happy with all four valves on cylinder number one, you now need to rotate the crank and put the next cylinder in TDC.

Due to the way the h22 (and most other engines) fire, the next cylinder to be brought to TDC is NOT number two as you would expect, it is number three.

One complete rotation of the crank will bring the cylinders to TDC in the following order:

1 – 3 – 4 – 2.

So repeat the previous steps for each cylinder. To be thorough, it’s worthwhile going round and just checking the clearances again. With any luck they will not have moved.

Now, in true ‘how-to’ fashion, its time to put everything back together again!

Fitting is the opposite of removal, just remember the little things like the cam cover support studs, and make sure your gasket is fitted nice, with a little sealant if you want.

Re connect the positive battery terminal, remember to remove the ratchet and socket from your crank pulley if you haven’t re fitted the bottom cover yet. Start her up and marvel at the sound of a sweet H22!

And I think that’s all folks; if I have forgotten/omitted anything important, please say!

Just having the confidence to try this job will save you time, money and as an added bonus should give you an interesting look at how the top end of your engine works.

Good luck all!

Dan.
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Post by Rocketrooney » Wed Jan 09, 2013 6:07 pm

Did you know you can use the p/s pump to turn the crank to save you having to jack the car of the ground, get a 19mm socket/spanner put it on the p/s pulleys nut and turn anticlockwise
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Post by nucleustylzlude » Wed Jan 09, 2013 7:39 pm

8-)

Good write-up bud.

Good tip on the P/S pump too. What about us with no P/S? :P

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Post by HiGhGuY » Fri Aug 01, 2014 7:31 pm

Hey, nice write up. I was curious about 2 things.

1.) In this write up, as well as some others I've seen, and a youtube video all for this same procedure, the valve clearance is being measured by sliding the feeler under the tappet screw. I have a copy of the Honda service manual, not a Helms or other 3rd party service manual, but the ones that Honda technicians use. In that manual, they show the clearance being measured in between the cam lobe and rocker arm. Does anyone else do it this way?

2.) How many of you guys use a torque wrench to torque the locknuts to spec... and the valve cover acorn nuts, and how many just do it by feel?

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Post by Vtecmec » Fri Aug 01, 2014 7:38 pm

HiGhGuY wrote:In that manual, they show the clearance being measured in between the cam lobe and rocker arm.
That's the correct and easiest way to do it.

Just on the above guide, there's no need to remove the bottom splash guard at all, as it has that hole for access to the bottom pulley bolt.

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Post by SPYDOR » Fri Aug 01, 2014 8:33 pm

I did my valve clearances last Friday and followed this guide a bit. Took about 20-30 minutes to get everything ready to start checking the clearances then took me about 2 hours trying to check the clearances on the 1st cylinder because the guide is wrong...

As vtecmec says you do not check the clearances between the rocker arm and the spring, you check them between the rocker arm and the cam lobe, as stated in the service manuals as well.

When you do it the correct way it is very easy, you can use a small feeler gauge and get all the valves checked and adjusted within an hour. Just push the feeler gauge in from the middle of the camshafts, don't try and push it in from the side the springs are on.

If you have power steering you can just turn the engine anti-clockwise using the pulley bolt in front of the oil dipstick. Simples!
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Post by GreenyUK » Fri Aug 01, 2014 8:41 pm

This correction is worthless with out pics :lol: :lol: new smiley needed mods :lol:
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Donald wrote:I think the best bet is to probably all try to enter together.

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Post by Vtecmec » Fri Aug 01, 2014 8:47 pm

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;)

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Post by GreenyUK » Fri Aug 01, 2014 8:50 pm

We'll arnt you mr efficient... :mrgreen:

:think: :think:

Where's the free 20k for all members.. :twisted: :lol:
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Donald wrote:I think the best bet is to probably all try to enter together.

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Post by Bri » Sat Aug 02, 2014 4:54 pm

Made Sticky. Nice work Sir 8-)

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