Adjusting Valve Clearances

[HappyGoLucky]

Hi there,

Few questions:

1. Is this type of procedure really necessary for an engine?

2. Is it likely that more 'damage' might be done trying to make these adjustments if nothing seems to be wrong with the engine? Problem is that I can't gaurantee whoever is making the adjustment is an "expert" -- just a little paranoid when it comes to making a physical engine adjustment and such a small change can do such catastrophic damage.

3. What sort of "issues" would I expect to encounter as a warning that this service is impending? From what I understand, if you can tell, it's sort of too late.

4. Approximate cost?

I have a 4-cylinder 98 Accord with 240000 KM on it, and I know this type of service hasn't been performed lately (or at all).

Thanks!

[enko]

Check what the manual recommends.

I would get the clearances checked, it's relatively straight forward. You might find they are in spec. Or depending on your goals for the car (ie. have it last forever vs sell it next year), you could decide if it's decently close enough to spec.

If they're out of spec, and you decide to put it in spec, it's not for the faint of heart, and you might have a bit of down time if you have shims on the buckets, because you have to order a ton of shims from Honda. But then again, it's a honda, might be lots in the city.

I had to reshim my new cams on my old car, it was a *****. Took like 2-3 weeks to get the shims in from the USA.

[sunnybono]

Hi there,

Few questions:

1. Is this type of procedure really necessary for an engine?

2. Is it likely that more 'damage' might be done trying to make these adjustments if nothing seems to be wrong with the engine? Problem is that I can't gaurantee whoever is making the adjustment is an "expert" -- just a little paranoid when it comes to making a physical engine adjustment and such a small change can do such catastrophic damage.

3. What sort of "issues" would I expect to encounter as a warning that this service is impending? From what I understand, if you can tell, it's sort of too late.

4. Approximate cost?

I have a 4-cylinder 98 Accord with 240000 KM on it, and I know this type of service hasn't been performed lately (or at all).

Thanks!

A valve adjustment is mostly labour intensive. It should take approx 1 to 1.5 hours to do the work. You will require a new rocker cover gaskets and while you're at it, you should replace the gromets on the rocker cover. When I used to own a honda, I had the valve adjust done once every 2 years. As I used to watch my mechanic do the work, it seamed very straight forward like creating the right gap in a sparkplug.
Since your car has done 240k km, I would suggest that you get it done atleast once. You car should last easily past 400k kms, if you maintain it right!!!!

Alternatively, if you haven't done the timing belt lately, you can do the valve adjustment the same time, which is usually recommended by Honda.

sk

[cipher]

Do it wrong and you get mashed valves and possibly damaged pistons.

[HappyGoLucky]

Yeah, I had my timing belt changed a couple of months ago, but like Cipher said, I'm concerned that doing this adjustment might cause me all kinds of serious problems -- and I'm not having any now -- sort of like a don't fix what ain't broke sort of situation! :|

[Spud72]

Checking them is very easy. As a matter of fact, I'm doing it right now. If they are out of spec, its a bit of work as the cam has to get removed.

Not tough or rocket science by any stretch, but not for the timid. If the person takes their time they should be able to do it in an evening.

Don't worry about smashing pistons and such. They'd have to be so grotesquely out for that to happen, I don't even know if it would be possible.. especially with a Honda engine.

Honda's are notoriously conservative with their maintenance schedule though. I've actually never worked on one that wasn't withinspec at their service interval. They really are that good. One thing they know how to do is make a reliable motor. :)

Even my bike which I'm working on right now - and arguably, this is more of a PITA than your car would be.
http://www3.telus.net/public/bernse/teardown.JPG

[eelfliw]

If your valve clearance is getting big, you'll hear it as tapping sound when the engine runs.

This shouldn't happen on big pushrod V8s as it comes with hydraulic valve lifters. It's only on the OHC engines.

IF you don't know what you're doing, you can create a lot of problem for yourself. If you do, then it's a simple task. Especially easy if you have screw type of adjusters. If it uses shims, then you have to have a supply of different sizes on hand or another car to drive to the dealer for new shims.

Some shims can be removed with a valve depressor (special tool). Others require camshaft removal. If you don't know what a camshaft is, don't remove it. Installing it wrong may bent all the valves or notch pistons.

In general, it's a fun activity to keep you busy if you know what you're doing. If not, let a mechanic do it when you hear tapping sound from the engine.

[Spud72]

If your valve clearance is getting big, you'll hear it as tapping sound when the engine runs.

Not necessarily. If it is terribly out, you might hear it. But you necessarily won't hear it for sure.

[maniacshopper]

adjust valve clearances is what they call a physical tuneup. As the engine mileage racks up, check to see if out of sync. that is if you want to keep the car in tip top running condition.

Anybody that mods the engine should do this as part of checking the internals before doing heavy modding.