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DIY: H22A4 Valve Adjustment! by JLUDE

95K views 181 replies 73 participants last post by  Ruxus Cantu 
#1 · (Edited)
Adjusted my valves on Saturday. First time for this motor (69K on the clock). Made a noticable difference. The power band is smoother. I used to have some roughness between 4-4.5K rpms...that is totally gone now and the motor idles quieter!

here's the proceedure:

1. Download the helms manual! http://spoonhonda.com/downloads.htm

2. Disconnect the negative battery cable (closest to the front of the car)

3. Remove the Valve cover

4. Remove the spark plugs

5. Rotate the engine with the crank pulley bolt (19mm) according to the Helms manual to get each cylinder you're adjusting to TDC on the compression stroke.

6. Check and adjust the exhaust and intake vavles on each cylinder at TDC, make sure you use a torque wrench to torque the valve nuts back down!

7. Intake valve clearance (0.15 - 0.19mm)

8. Exhaust valve clearance (0.17 - 0.21mm)

here's the pics!

Step 1: Remove the driver side front wheel. that little hole is where you'll put your 19mm socket and extension to turn the engine counter clockwise (left).


Close up of the hole to the crank pulley bolt:





Spark Plug wires Removed, do not disconnect from the distributor cap!


Shows what bolts/nuts need removed to free the valve cover:


Remove nuts with 10mm socket wrench and extension:




Remove the vacum line that goes to the intake:














Rotate the engine, counter clockwise only to get each cylinder at TDC! Follow the helms manual for proper alignment of the cam gear for each cylinder to be at correct, TDC!


Finally the valve clearances are checked as shown:


This would be a LOT easier with the tool that Honda sells for this purpose. It can be done without it but it requires some trail and error to get each valve right!


Reassemble the Valve cover as removed. It's a good idea to clean it well and spread some high temp gasket maker (slicone) on the seam before reinstalling to prevent oil leaks! Do not toque the nuts that hold the valve cover down tight! Hand tight only with a small wrench, I used about 15 ft lbs, if that...just until they seat. Enjoy a smoother running motor!

- JLUDE
 
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#4 ·
Thanks!

The tool that honda sells... what exactly does it look like? Does it hold the screw in place while turning the nut or something?
That's exactly what it does. It's a 10mm socket with a hole though it and a little screw driver that you stick through the hole to hold the screw from turning as you tighten down the nut.
 
#12 ·
How exactly do you adjust the vavles.. meaning do you put a certain size feeler gauge in there and tighten it down or... (is it detailed in the manual?)
You insert the size feeler gauge you want it to be. For instance if the specified range is .15 - .19mm then insert say a .17mm gauge. If it slides in with no resistance the clearance is too loose. If it's hard to get it in there then it is too tight. The clearance is right when the correct gauge goes in with slight drag.

- JL
 
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#14 ·
Nice write up brotha! Rep to ya!

This procedure is alot easier than you think: once you get the valve cover off and actually look at whats involved, there really is not alot of room to mess it up. Loosen nut, slide feeler gauges, tighten nut. Taa-daa!
 
#18 ·
That's normal if it's been regular oil (non-synthetic)
 
#17 ·
you can also help your car pass smog by adjusting them on the loose side before you go and tightening them back up afterward

you will have less lisft and less duration menaing less fuel is going in so less emissions coming out

i saw abouta 75 point decrease in nox by adjusting to the loos service specs rather than tight
 
#20 ·
Are intake and exhaust done at the same time?

For example, start with cylinder 1 at TDC. Make adjustments for the intake and exhaust, then move to cylinder 3? Or do intake for 1-4 then exhaust 1-4?

I'm not sure if it matters, but I thought I'd just throw it out there.

Very helpful pics :emthup:
 
#24 ·
#25 ·
#26 ·
Awesome job helping us with this write up and all man.. Gives me sumthing to do when i get time off again .. bout how much time do you think it should take for first timer's... About how much time should we set aside for doing the entire procedure. Would 2 hour do..or would this be a afternoon job.
 
#31 ·
wow, this write up makes it looks SOOO easy, im MORE than sure i could handle this. and i dont know jack about shit. and forgive my absolute noobiness, but what exactly does tightening vs loosening do? this made me want to learn a whole HELL of alot more about everything i can, but i cant do something if i dont know my goal.
 
#33 ·
wow, this write up makes it looks SOOO easy, im MORE than sure i could handle this. and i dont know jack about shit. and forgive my absolute noobiness, but what exactly does tightening vs loosening do? this made me want to learn a whole HELL of alot more about everything i can, but i cant do something if i dont know my goal.
When you tighten the adjusting screw (you turn it clockwise) righty-tighty and that will make the gap between the cam lobe and rocker arm (the gap where you stick the feel gauge) smaller.

if you turn the adjusting screw counterclockwise (left) then the gap gets larger. You want the gaps to be within the tolerances listed: 0.15-0.19mm intake and 0.17-0.21mm exhaust.
 
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