Valve clearance adjustment?


#1

Acura Integra 1999, 80k miles, Auto.

I am working on changing timing belts, drive belts & water pump.

So wondering if I should also do the valve adjustments - if I were to do it, there are about 12 parts that I need to get - Valve cover gasket, Spark Plug seals (4) & Valve cover seal washers (7). I don’t know the price of parts - but hoping incremental cost would be $100 (parts & Labor).

Should I do it?

One mechanic said my car doesn’t need it. Acura dealership did an inspection but did not say my car needs it.

Any suggestions?


#2

I think you will need the valve covers anyway just to do the timing belt. The valve cover gasket comes in a kit with everything you need and it is no where near $100 for parts. Labor for the valve adjustment might push it to around $100 though.

You should do it.


#3

From what I can tell, these are the typical Honda adjustable valves, only requiring a feeler gauge, an open end wrench, a screwdriver, and some patience. Good idea to adjust them.

p.s. - just google Integra valve adjustment, lots of info out there. And you may need the special tool that lets you easily adjust and lock the adjuster, depending on your Integra’s setup.

But they sure look a lot like the adjusters on my (former) CB550 from 1978!


#4

Out of all the Honda’s/Acura’s I’ve owned over the years, the only time I performed a valve adjustment on the engines is when the valve train was taken apart and the valves required adjustment when reassembled. Other than that I never had to adjust the valves. And this would be when the engine had over 200k miles. Although I did get a Civic in one time that had very loud valve noise. And when the valve cover was removed, it was found one of the rocker arms was missing the valve lash screw and the lock nut. But once those were replaced the valve lash was never adjusted again.

Honda recommends that the valve lash be checked if the valves make noise.

Tester


#5

FWIW: I adjusted the valves on my 1999 Honda Civic somewhere around 100,000 miles. There were no symptoms - but several were somewhat out of spec, and the engine seemed to run a little smoother afterwards. Texases’ said it right. I replaced the spark plugs and cleaned the cap and rotor at this time, too, so it’s hard to say what effect each procedure brought. I have never needed any new gaskets, seals, etc. and I think you won’t either.


#6

Valve lash should be checked about every 30k miles. The cars I’ve serviced have been mostly European and Asian and the majority of those cars that required lash inspections (screw or shim) adjustment needed it. Too loose is not good and too tight is even worse.

Valve lash is like gambling. Some win and some lose. The reason for inspection is to make sure that you’re not on the loser board.


#7

Everyone is forgetting. This is a 1999 Acura. OBDII. If a valve should go out of adjustment, the Check Engine light would come on with a misfire code.

Tester


#8

The problem with waiting for a misfire code to occur due to a tight valve is that by the time the engine has a miss and the cylinder misfire is present the damage is already done. Damage to the valve seat and face will occur in a few miles.
Depending on the length of time the valve has been running tight the miss may never go away or it may go away, temporarily, after properly adjusting the valve.
Once a microscopic burn trail starts on the valve face or (usually) the valve seat it’s only going to get worse.

There is no code for too loose, which may be very apparent if extremely loose or not so apparent in many cases. In a case of too loose damage can occur to the lash adjusters and cam lobes due the hard coating being beaten through along with valve stem mushrooming.


#9

If a valve is out enough to misfire that’s pretty bad.

I’ve owned a Civic and 3 Accords ranging from 1975 to 1988 and I adjusted the valves regularly on all of them.


#10

I want to add a little to my post. I’ve only had two Honda’s, a 93 civic and a 97 accord which I still have. I checked the valves at 30k on both, which is the recommended on both vehicles. I did the civic every 30k until it was totaled at around 90k. I have only done the accord twice, once at 30k and again at 150k. I have never had to adjust the valves, they have always been on spec.

For the OP, I do believe you have to pull the valve cover to change the timing belt so you might as well check the valves while your at it, especially if you’ve never had them checked.


#11

And Honda’s are supposed to be advanced design vehicles…Complete with solid valve lifters that require adjustments at very vague intervals…


#12

The reason I have the opinion I do on this issue is because I’ve had to inspect and adjust as necessary the valve lash on many foreign cars, the primary ones that use mechanical lifters. Nissan, Subaru and Honda being the primary ones for the screw and nut method.

At 2 of the dealers I worked for and in my own shop I did all of my own cylinder head valve work. There’s a lot to this issue so I won’t go into it all except for a few brief points.

Assume an intake spec is supposed to be .008 and it’s actually at .013. It will sound normal but it’s goint to cause the valve train to take more of a beating. That’s also going to cause the valve to not open as much. A measly .005 may not sound like much but with use that’s a considerable amount of air/fuel being obstructed.
If an exhaust valve is tight at .002 there won’t be a problem, MAYBE. One overheating episode or a little more valve face dishing and that valve won’t last long.

Regarding the loose valves and mushroomed stems I’ve often had to use a small file to remove the burrs from the stem (caused by excessive lash) rather than score a guide.

Inspection of other exhaust valve faces and seats during a valve job for say 1 burned exhaust valve have revealed microscopic channels in the face or seat due to tight lash.
With the naked eye it may appear fine but under a magnifying glass it can be seen.
Eventually that microscopic channel is going to look similar to an aerial view of a river bed.

In the case of some of the older Nissan they would even throw a rocker arm off if the valve was too loose and the engine was revved high.
It just seems to me that regular inspection and adjustment of the lash as needed optimizes engine performance and eliminates the risk of serious and expensive cylinder head damage.

(The poster boy for this would be the guy who apparently adjusted all of the valves on his new Subaru to 0 lash and ended up with a trashed vehicle that only had 7k miles on it. In this case both heads (all of the exhaust valves and seats) were trashed so badly even the cylinder heads could not be repaired.)

Even Harley Davidson started using hydraulics in 1949. :slight_smile:


#13

I imagine it’s getting harder to hear loose valves, the direct injection engines make a bunch of fuel injector noise.


#14

I have no experience with direct injection but I’ve heard some reliable rumblings there could be a few problems developing with this system.
Apparently some engines are developing an abnormally large amount of deposits behind the heads of the intake valves as the injectors are not in place to (sort of) keep them cleaned off. We’ll have to wait and see what happens with this one and it could be that a more regular induction service could be required.