How to perform a valve lash (clearance) adjustment on a SOHC Honda Civic, namely a 90-00 D-series and possibly others. These pics are of an OBD2 D-series in a VX.
Your engine may not have the cbr coil packs.
When your valves need to be adjusted some of the symptoms can be excessive valve train noise, smog fail HC, a small drop in performance, driveability, and fuel economy. If your valve lash is too tight it can cause you to wear down the cam resulting in a costly repair (not to mention lots of metal shavings circulating through your engine).
According to the manual, you should adjust the valves every 12 months or 15,000 miles. You will also need to perform a valve adjustment if you loosen the head bolts for any reason (ie mini-me or headgasket change), change the cam, or disassemble the valvetrain.
Liquid Gasket ie Honda Bond
Possibly a Valve Cover Gasket Kit
Feeler Gauges .007, .008, .009. 010 (This includes the VX and most other D-series, but other models may vary so check your specs)
10mm Jam Nut Valve Adjustment Tool
For the feeler gauges I recommend Craftsman 40802 approx $10 from Sears. For the Valve Adjustment Tool I recommend Alltrade/Powerbuilt 648827 approx $13 from Amazon.com.
These are the tools I used:
Ratchets 1/4, 3/8, 1/2 inch drive
Sockets 10mm short 1/4 drive, 10mm 3/8 drive, 19mm 1/2 drive, spark plug socket (small)
Long Extensions, 3/8 & 1/2 drive
Torque Wrenches (One capable of 80-160 inch/lbs, the other 80 ft/lbs)
Flat Blade Screwdriver
The engine must be stone cold. Let the car sit overnight. Note - you can't do a valve adjustment on a head before you install it on the block because torquing it down will change the thickness of the head.
Lift the Car
Wheels shown not Honda factory VX.
Pull the ebrake, put the car in neutral, chock a rear wheel, jack up the front end, put a jackstand under the driver's front jack point, let the car down, pop the hood.
Remove the driver's front wheel (loosen lugs before you lift the car if you don't have an impact).
Remove the spark plugs
Pull the spark plug wires out of the valve cover and set them aside (mark them with a sharpee, one closest to crank pulley is #1). Removing the spark plugs makes it much easier to rotate the engine by hand.
Remove Valve Cover
Remove the air breather hose from the valve cover.
Remove the core support ground wire from the valve cover.
Remove the bolts holding down the valve cover and gently pry it up at a point that isn't critical to sealing or tap it with a rubber mallet.
Remove the 10mm bolts holding the upper timing belt cover and remove it.
Your engine may not have the dual VTEC solenoids.
Put a socket on the crank pulley bolt, run an extension through the access hole in your wheel well, set your ratchet to loosen, and crank the engine counterclockwise until the "UP" etching in the cam is pointing straight up indicating cylinder 1 is at tdc on its compression stroke. Watch the rocker arms as you rotate the engine. They must be completely at rest when you adjust the valve clearance. All the valves for a particular cylinder will be at rest when that cylinder is at tdc on the compression stroke.
Cylinder #1 Valve Clearance
Check the valve clearance on cylinder 1 (closest to crank pulley). Use your .007 feeler gauge on the intake side and the .009 on the exhaust side.
The .007 should slide in with a slight drag on the intake side. But the .008 should not be able to fit. If it does, insert the .007, loosen the lock nut with the jam nut tool and turn the screw gently using two fingers. When you feel it contact the feeler gauge, gently pull back on the gauge. It should be locked in place. Loosen the screw just a hair until you can barely free the gauge (it should drag). Be careful not to press down on it with the jam nut tool. Now try inserting the .008 again. It should not fit (don't force it).
Repeat this using the .009 and .010 on the exhaust side.
Cylinder #3 Valve Clearance
Next is #3. The firing order is 1, 3, 4, 2. Turn the crank pulley until the cam pulley turns 90 degrees counterclockwise. The "UP" etch mark will face the front of the vehicle. Check/adjust the valves.
Cylinder #4 Valve Clearance
Next is #4. The "UP" etch mark will face downward. Check/adjust the valves.
Cylinder #2 Valve Clearance
Next is #2. The "UP" etch mark will face the rear of the vehicle. Check/adjust the valves.
Go through the cycle a few times until you are comfortable that each valve is consistent. Then torque the lock nuts and check it one last time.
Reinstall the Valve Cover
Clean the gasket mating surface. Put the upper timing belt cover in place. Put the valve cover gasket into the valve cover and apply the liquid gasket at the sharp corners where the distributor and cam pass through the valve cover. Press the valve cover in place and install the bolts in a swirl pattern starting in the center. First torque them by hand and then with the torque wrench according to the spec. If you over tighten these bolts they break very easily.
Re-install Spark Plugs
Yes, I know! Autolites are crap. But I need screw cap plugs and I'm not bank enough to replace these with Iridium NGK's at least until they go bad.
I don't exactly index the plugs as that would require special washers. But I mark them with the sharpee so I can make sure the ground strap doesn't face the intake ports.
Reinstall the Wheel
Hold the wheel in place and hand tighten the lug nuts so the wheel fits evenly. Then tighten them as much as possible before putting the car on the ground and torquing them to spec.
The rest of the installation procedure is the reverse of removal.
Reset the ECU
On most Civics you simply unplug the battery or remove the 7.5A fuse under the hood for 5 seconds.
Test Drive the Vehicle
Don't wait until Monday morning to find out if you did something wrong! Make sure no oil is leaking from the valve cover and that there's no excessive valve train noise or other obvious problem.
In most cases you'll notice the car is more peppy, the idle is smoother, and you'll pick up some mpg.
Just did a timing belt change last week and a valve adjustment was part of the protocol. I didn't do it because the Timing Belt & Water Pump took a little longer than expected and I needed to get to work. Seems to run fine but I'm going to do it this weekend.
Reading your write up this was my main observation: How clean the top of your head looks compared to mine
Typically the engine needs to be under 100deg when the valve clearance is adjusted.. just remove the plug wires from the plugs and take the valve then the upper timing to allow the timing marks on the front of cam...
________________________ An optimist is someone who falls off the Empire State Building, and after 50 floors says, 'So far so good!' honda wheels
I first adjusted my valve clearance several months ago and decided to adjust it half way between the specs in my haynes manual. It gave me .007 -.009 for my intake and .009 -.011 for my exhaust. Well I did the adjustment the way the book directed which is the same as above and immediately my car lacked power. To get it running correctly I had to advance my timing 10 or 15 degrees. It still lacked power and mileage suffered by about 4 miles per gallon. I decided to try again today and adjusted the intake at .007 and the exhaust at .009 and made sure the gauge dragged heavily when removing it. I made sure my timing was not advanced when doing this procedure and was at exactly TDC for every valve. When I started the vehicle up it didn't want to start or even run. I eventually had to advance my timing 10 degrees so it will work at all and it still lacks power when I put any load on it. Whether it be going up a hill or whatever. I'm thinking I'll try again latter this week to retry the adjustment but would really like some suggestions if anyone else has encountered this problem or has a possible solution. I wish I had never checked them because before I could actually make it up a hill easily. Thanks for any help.
Well I went step by step from above following the direction to a T. My car is running OK but only after I advanced the timing 10 degrees. At 0 has no power what so ever at 5 it ran somewhat but stalled on me and wouldn't restart. So 10 seems to be my magic number. What could be the problem? What might I be doing wrong. I've had my Civic for 5 years and have done a lot of work some hard some simple but this has me perplexed.