Service & Maintenance Valve Clearance Adjustment Information 6th Generation Honda Accord CG8 -F18B2E

Discussion in '6th Generation (1997-2002)' started by Ichiban, Tuesday 26th Mar, 2013.

  1. Ichiban Founder Staff Team

    England CJ Leeds
    This is Honda set procedure how to do the valve adjustment.

    Remove the cylinder head cover.
    Set No. 1 piston at TDC. ‘‘UP'' mark (A) on the camshaft pulley should be at top, and TDC grooves (B) on the camshaft pulley should align with the cylinder head surface.
    Adjust valves on No. 1 cylinder.

    Intake: 0.26 mm (0.010 in.)±0.02 mm (0.0008 in.)
    Exhaust: 0.30 mm (0.012 in.)±0.02 mm (0.0008 in.)

    Top Tip

    Valves should be adjusted only when the cylinder head temperature is less than 38°C (100°F).
    After adjusting, retorque the crankshaft pulley bolt to 245 N·m (25.0 kgf·m, 181 lbf·ft).

    CG8 AOCUK 6th gen accord Valve Clearance.JPG

    Loosen the locknut (A) and turn the adjusting screw (B) until the feeler gauge (C) slides back and forth with a slight amount of drag.

    CG8 AOCUK 6th gen accord Valve Clearance2.JPG

    CG8 AOCUK 6th gen accord Valve Clearance2a.JPG

    Tighten the locknut and check clearance again. Repeat adjustment if necessary.

    CG8 AOCUK 6th gen accord Valve Clearance3.JPG

    Rotate crankshaft 180° counterclockwise (Camshaft pulley turns 90°). The ‘‘UP'' mark (A) should be on the exhaust side. Adjust valves on No. 3 cylinder.

    CG8 AOCUK 6th gen accord Valve Clearance4.JPG

    Rotate crankshaft 180° counterclockwise to bring No. 4 piston to TDC. Both TDC grooves are once again visible. Adjust valves on No. 4 cylinder.

    CG8 AOCUK 6th gen accord Valve Clearance5.JPG

    Rotate crankshaft 180° counterclockwise to bring No. 2 piston to TDC. The ‘‘UP'' mark (A) should be on the intake side. Adjust valves on No. 2 cylinder.

    CG8 AOCUK 6th gen accord Valve Clearance6.JPG

    Please do post your version of the DIY and full fill you end of the bargain:Smile:
  2. carrind Junior Member ☆ ☆ ☆ ☆ ☆

    This looks straight forward (famous last words). Are these clearances the same for the CG9 2.0 ltr engine? Also is it good practice to replace the cylinder head cover gasket, or should it be ok?
  3. Ichiban Founder Staff Team

    England CJ Leeds
    Only if it is showing signs of perishing then replace it.Honda dealers won't stock the gasket it will be next day order anyway.
  4. AndyB1976 Valued Contributor ★ ★ ★ ★ ☆

    United Kingdom Andy Aberfoyle
    This is my 6th Generation SOHC F18B2(f18b3,f20b6) Valve Clearance Check and Adjust including Spark Plug Inspection.

    This guide is quite image heavy and has a seemingly extensive tool selection, although you could get away with a few less than I have listed in order to complete the job. Some tools are duplicated like the feeler gauges and 10mm spanner/socket. I was going to separate the Spark Plug section onto a separate Howto but decided to leave them in as a complete procedure.

    I was able to complete the job without the need for raising the vehicle by using a long 500mm wobble extension bar. If you don't have this or can't stack a few wobble extensions together you will need to get the jack and axle stands out and nearside (passenger-side) wheel off.

    Remember to securely support any lifted vehicle.

    The adjustment must bedone on a cold engine 38°C or less so before you proceed ensure the engine is preferably stone cold.

    Another crucial point to be aware of is the official recommendation to re-torque the crank bolt to 181ft-lbs after the procedure is complete.

    I have two of the three Halfords Pro Torque wrenches but not the larger one to cover this torque spec. Having watched and read howtos on cracking Honda Crank Bolts,requiring acetylene or the pulley holding tool and breaker/cheater bars up to 5feet in length with mechanics swinging or jumping from the end of them I formed the opinion that my 10inch ratchet would cause no problems.

    Tool List.

    1.Feeler Gauge Straight ( Laser)
    2.Feeler Gauge Offset ( CTATools)
    3.Long Bent Nose pliers ( Tekton 3491)
    4.Honda Liquid Gasket({excellent price at the time})
    5.Draper ½” 500mm Wobble ExtensionBar (
    6.Halfords ½” 19mm Impact Socket
    7.Stanley ½” Ratchet (Screwfix)
    8.Penetrating Spray (unused)
    9.Halfords Professional Torque Wrench 8-60Nm
    10.Draper Pry Bar (
    11.Halfords 3/8” FlexiRatchet
    12.Gearwrench 10mm Long Pattern offset/ratchet spanner (
    13.Halfords 3/8” 250mm Wobble Extension Bar
    14.Stanley Spark Plug Socket 16mm
    15.Halfords 3/8” 10mm socket


    cont' Valve Tools

    16.Flat Screwdriver
    17.10mm ring spanner
    18.Powerbuilt Jam Nut Adjustment Tool 10mm ( Alltrade 648827)


    Accessing The CrankBolt.

    It might be wise to test that your extension bar(s) and socket fit eliminating the need to follow the raising and securing the vehicle procedure.

    I found it easier to place the socket on the crank bolt by hand, then inserted the extension bar into the socket. With the 15degree off-axis rotational capability it allows you to turn the crank even with the wheel still on the car. The wobble feature is effectively acting as a small UV/CV joint.


    Engine Bay.

    The primary ancillaries of the rocker cover in this howto are highlighted below. I usually unclip a couple of the HT Leads from the plastic clips/guides just for a bit more freedom of movement when removing them.

    You will be undoing 5 bolts and removing 4 HT Leads and two breather hoses then the rocker cover itself. The bolts once fully unscrewed from the head, can be left in the rocker cover. The rubber washers/seals will hold onto them whilst you lift it away.


    Spark Plug removal.

    I decided to remove the spark plugs in order to make the crank shaft rotation easier. With the plugs removed the compression stroke is negated as the air will escape through the opening left by the plug allowing the engine to freely rotate.

    I usually start by cleaning around the leads and rocker. Might seem unnecessary but I want to reduce any debris falling down the Spark Plug channel then into the cylinder.


    Once you are happy its clean you can grab the around the middle and twist it back n forth then pull it up and out.


    Now the HT lead is out, the top of the Spark Plug will be visible down inside the sleeve.

    I use a 250mm extension bar and spark plug socket. This socket has a rubber sleeve/retainer inside which will hold the Spark Plug Insulator. You will feel some resistance as this slips over it, but keep on going and eventually the socket will seat on the hex collar with a positive action. Once seated, I'll just crack it with the ratchet then spin it out by hand then lift it up. The plug needs quite a few revolutions before it is free, maybe about 20 full turns.


    Once the plugs are out I'll wrap them in paper roll as they will be going back into the engine. I like to keep the plugs from contaminants and also in cylinder order so I can give them a quick inspection prior to re-installing them.


    Condition Guide NGK Spark Plugs USA

    Removing the Rocker Cover.

    Now the HT Leads are clear pullout the PCV Valve


    Release the breather hose clip, you might lose the spring clip as you pull the hose away so 'park it'back up at the upper clip then pull the hose up and off.


    Undo the 5 10mm bolts


    Ease the cover off, pry gently here if needed..


    Cover off reveals valve train. I've highlighted the intake valves, the exhaust valves are just below out of shot. There are sixteen valves but they might not all need adjustment, use the feeler gauges. I think I adjusted 6 valves some exhaust and some intake. I had to unclip the loom harness for clearance in order to use the Jam Nut Tool on the intake side.


    Turn the crank until Cylinder 1 is at Top Dead Centre (TDC). I never took the upper timing belt cover,however you can identify this from the other side of the camgear. Cylinder 1 (Piston1-TopDeadCentre) has an designated arrow and two indicator grooves that should align to the head. You need to rotate the crank 180degrees which rotates the cam shaft (gear) 90 degrees. These indicator grooves will be used to determine the remaining piston positions.


    Now you must be aware to move across the valve train in the correct order once you have determined TDC for the relevant cylinder.

    This sequence is 1 3 4 2 (refer to valve train image)


    One you are sure you have the correct cylinder set, then insert the correct feeler gauge. The exhaust and intake have different gaps so be sure to use the right feeler. I put white tape on the handle of the intake feeler to quickly identify it.

    There should be slight drag when it is set correctly. Unless you have experience this could be quite ambiguous; just how much drag is slight drag? You might be lucky and find that some valves are within spec – not too tight, not too loose. Use these ones as a guide. Don't be ashamed to go around all the valves a second time to ensure you are happy with the job.

    The Jam Nut Tool makes this job a bit easier. There is enough leverage on the handle to crack the locknut, the blade can rest in the adjustment screw. The tool does not need to be removed, insert the feeler , adjust until you are within spec then turn the handle back to the starting position which should be close to the torque spec on the lock nut.

    Intake: 0.26 mm (0.010 in)+ 0.02 mm (0.0008 in)
    Exhaust: 0.30 mm (0.012 in) + 0.02 mm(0.0008 in)


    Clean up the mating surface.


    I had replaced my rocker cover gasket a few months ago. If it looks ok then just reuse it but you still need to apply some liquid gasket on the corners. I took a few minutes to clean up the remnants of the old liquid gasket then reapplied the new. It is recommend to install this in under 5 minutes before it starts to cure.




    Torque the cover back down at 7.2ft-lb. I usually work from the centre bolt, outward. Attach your PCV and breather hose.


    Reinstall Spark Plugs.

    Should you apply anti-seize?

    I've posed this question elsewhere and have also seen it asked by other folk. The consensus was pretty much split. There is an argument the plugs could seize in the head without it, the counter argument is that the plugs should be 'dry torqued'. A lubricated thread (a wet torque) would in effect cause the plug to the over torqued, possibly even stripping the thread.

    The Honda manual instructs your to apply a small amount of anti-seize to the threads, yet NGK themselves recommend to leave dry. I have always dry torqued the plugs personally.

    Slip the plug inside the spark plug socket. Slowly lower it down on the extension bar and slowly tighten it, finger tight. You should get about 20 revolutions until the plug begins to seat. If you feel you can't turn these in after a couple of turns back it out and try again. Do not try and Rambo these plugs in with the ratchet – you could strip the head and end up in a world of grief.

    When happy that they have seated,torque them to 13ft-lbs. Now put your HT Leads back in.


    Recheck your hoses are firmly in position, your wires and loom are all clipped back into position.

    You have now completed your Valve Clearances and Spark Plug inspection.
    Last edited by a moderator: Friday 14th Jun, 2013
    exec, Nels, Nighthawk and 2 others like this.
  5. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
    Top stuff Andy, AOC members are raising the bar on DIY guides :Thumbup:
  6. Ichiban Founder Staff Team

    England CJ Leeds
    par excellence stuff Andy.Another superb DIY from you :GoodJob:
  7. AccordCU2 Premium Member Club Supporter

    What a fantastic detailed DIY.
    Superb Andy.
  8. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
    That engines looks clean Andy, inside and out. Signs of a well maintained car (regular oil changes etc) :Thumbup:
  9. Ichiban Founder Staff Team

    England CJ Leeds
    Andy just put your images on our server for future reference, just in case in the future if Photobucket account closes the images will be here forever.:Wink:
  10. AndyB1976 Valued Contributor ★ ★ ★ ★ ☆

    United Kingdom Andy Aberfoyle
    Cheers guys...:Hey:

    FHSH until 2009, then looked after by myself following the OEM schedule. Oil changed every 6mths regardless of mileage - by that I mean low milage 2-3000miles it still get changed. Only OEM parts used.:Hooray:

    No probs.... :Niceone:
    SpeedyGee likes this.