[Dan]

What can I expect from doing a valve adjustment on my v6 engine with 112k?

Increased performance?

wondering if it's worth the trouble

 

[BLCKFLSH]

It's not like your engine will die, if you don't adjust the valves. The intake valves do tend to loosen over time, and the exhaust valves tighten. If your intake valves are loose, the engine will sound quieter after the valves are adjusted. I did the valve adjustment myself at 94k miles. If I had to pay someone else to do it, I would probably still be waiting. The fact that the exhaust valves tighten over time means they could possibly tighten enough to burn a valve, but the chances of that happening, before 200k miles, is slim and none.

 

[thisaznboi88]

I would do it. You could burn the exhaust valves if they get too tight. Just do it for the peace of mind. Especially if your doing the timing belt.

 

[gwiffer]

If exhaust valves tighten, you'll "burn" a valve. This means that the edge of the valve face/contact area or the valve seat itself has become physically damaged due to the extreme heat from not fully closing during engine combustion and exhaust. You should notice power loss and harsh engine operation, depending on how many valves are damaged.

If the intake valves loosen up, you'll notice excessive noise and maybe some power loss. The larger the clearance/lash at the valve stem, the less the valve will open at the apex of the cam lobe. This means less air/fuel in the combustion chamber and power loss.

I've been told that the valves should be adjusted at about 30K miles, because most of the wear and settling of the engine parts will occur in that period.

 

[BLCKFLSH]

I would do it. You could burn the exhaust valves if they get too tight. Just do it for the peace of mind. Especially if your doing the timing belt.

I don't see the connection between the timing belt job, and the valve adjustment?:dunno: I didn't remove any of the same parts doing the two jobs. For a rookie, shade-tree guy like myself, those two jobs are too much for one weekend, much less the same day. I did the timing belt, and valve adjustments two months apart.
IMO, if the valves are set correctly from the factory, it would be quite a while before the valves became tight enough to burn one. I set my valves at 94k, and only a couple of them were slightly under spec. (.010in.) That's only .002in. difference from the middle of spec range, so I think I could have easily gone 200k miles without fear of burning a valve. I did do the valve adjustment, and I'm glad I did, because I want the engine to run as smoothly as possible, but I was in no way in danger of burning a valve.

 

[07AccordEx-L]

The valve adjustment maintenance is usually done the same time as timing belt according to the Maintenance manual if I'm right.

 

[nehonda]

The only connection between timing belt change and valve adjustment is the valve cover which has to be loosened in order to remove the upper timing belt cover. Once loosened the valve cover could leak, so its better to remove it and change the gasket especially if its 10+ years old. If you have the cover off, you might as well check the valve clearance and adjust if needed.
Now having said all that, I have not adjusted the valves on either of my 6th gens even tho the timing belts were replaced at 100k. Valves are still nice and quiet, so I'll wait for them to tell me its time.

 

[BLCKFLSH]

The only connection between timing belt change and valve adjustment is the valve cover which has to be loosened in order to remove the upper timing belt cover. Once loosened the valve cover could leak, so its better to remove it and change the gasket especially if its 10+ years old. If you have the cover off, you might as well check the valve clearance and adjust if needed.

You don't have to loosen the valve cover on my J30 engine, or did I miss a step in the service manual? The upper covers came off without any trouble. The timing belt kit I bought had the valve cover gaskets included, and it made me wonder why. I know the timing belt, and valve adjustments are due at the same mileage, but I wouldn't try to do both jobs the same day, especially if it was my first time doing them.

 

[thisaznboi88]

you do it at the same time because you have to remove the same crap. IM, tb and then you can access the valve cover and replace the spark plug seals and spark plugs. Then after your done drop in a new valve cover gasket. I like to do things once and do it right. I dont wana go back to take crap apart. It took me 2 days to do the Tb, clean out the im and TB, valve adjustment on my dad MDX.

for the timing belt I replace everything, seals, idle pulley, tensioner, spark plugs, valve cover gasket, spark seal, water pump, coolant flush, thermostat, cleaned stuff, and there a few more stuff that I replaced. I hate doing major car work and would like to have it all done in 1 shot if possible.

If you were to send the car to honda they are going to charge you even more if you do it separately then together. So better to just do it all at once.

 

[BLCKFLSH]

I still don't get it. Why would you remove the intake manifold, and valve covers, to change the timing belt (on a J30 engine)? I did the timing belt, and the valve adjustment, and didn't remove any of the same parts for each job.

 

[thisaznboi88]

Well good for you. I know it can be done, but I am pretty sure I did a lot more stuff then you.

FYI here a DIY if anyone is interested.

http://tl.acurazine.com/forums/showthread.php?t=695821


He didn't change out the Cam seal. Did you change you cam seals? I also replace the intake runners with a set of PnP.

Its way easier if you take off the IM since the rear spark are a b*tch to take since you need the right tool and the strut bar is in the way.

 

[BLCKFLSH]

I don't think you understand what I'm saying. I'm not talking about cam seals. I'm saying it's not saving any time trying to do the timing belt job, and the valve adjustments, at the same time, because there are no common parts to remove. You don't remove the intake and valve covers, to do the timing belt. And you don't remove any timing belt related parts, to do valve adjustments.

 

[justinsomniac]

Is there a way to know if it's already been done? I just bought mine a couple months ago with 149k and I was told the timing belt service had been done, but found out the seller was a little shady with some other things, so I'm thinking he cut corners and might have not done the service completely (tensioners, etc.) and may have not done the valve adjustment. The car drives like a car with 150k so I can't exactly pinpoint the shortcomings it has.

 

[gwiffer]

Unless the previous owner gave you a service receipt/invoice, I would look into replacing the TB/WP/all relevant parts and adjusting the valves.

 

[1-Old-Man]

Would someone please explain to me just how the exhaust valve adjustment "tightens" itself? I can understand how it happens with the intake, where vibration might loosen the adjuster or wear of the top of the valve stem might cause the gap to grow. In all the years I've been playing with wrenches, and that is quite a few years, I have seen many a bolt or adjustment loosen itself, but I have yet to see a single bolt or adjustment somehow tighten itself. What I can understand is if the valve seat or the edge of the valve face has burned or worn excessively that the valve will ride higher in the head, giving the illusion that adjustment of the valve might be needed, but if that is the case it seems tome that what is needed is a valve job, not a valve adjustment. So can someone explain how this happens, this "tightening" thing?

 

[Drew03Accord]

It's not like your engine will die, if you don't adjust the valves. The intake valves do tend to loosen over time, and the exhaust valves tighten. If your intake valves are loose, the engine will sound quieter after the valves are adjusted. I did the valve adjustment myself at 94k miles. If I had to pay someone else to do it, I would probably still be waiting. The fact that the exhaust valves tighten over time means they could possibly tighten enough to burn a valve, but the chances of that happening, before 200k miles, is slim and none.

Had mine (i4) done at the dealer. Didn't see a difference in sound or anything. The only thing I noticed was that they cleaned the engine.

 

[nehonda]

The mechanical valve adjusters never change settings. The valves only need to be readjusted to compensate for wear in the valve train. The exhaust valve adjustment gets tighter because the valve and seats wear down due to the hot exhaust. This makes the valves sit higher in the head reducing the clearance. As long as the wear is even they will continue to seal and no valve grinding or replacement is needed.
The intake valves wear very little since they stay nice and cool. They get looser due to the wear on the cam and rockers.

 

[ezshift5]

The exhaust valve adjustment gets tighter because the valve and seats wear down due to the hot exhaust. This makes the valves sit higher in the head reducing the clearance. As long as the wear is even they will continue to seal and no valve grinding or replacement is needed.

Always good to hear your sage take on areas of interest to this sailor.

Would it be a fair statement that exhaust valve wear (uneven) would be reflected in less fuel economy? Any other symptoms you can think of appreciated big time...............

(Just like your take on Iridium spark plug longevity: thanks again)

all the best, ez....

 

[COOLONE]

Where I have seen with valves that "tighten over time is Where the valve starts to seat deeper into the seat. Not alot[although some cases YES] enough to warrant adjusting and hope it doesn't keep sitting deeper. Rare, but some cofigurations or maybe its metal temper tend to tighten. Hopes that helps

 

[AT93]

The mechanical valve adjusters never change settings. The valves only need to be readjusted to compensate for wear in the valve train. The exhaust valve adjustment gets tighter because the valve and seats wear down due to the hot exhaust. This makes the valves sit higher in the head reducing the clearance. As long as the wear is even they will continue to seal and no valve grinding or replacement is needed.
The intake valves wear very little since they stay nice and cool. They get looser due to the wear on the cam and rockers.

intake valves stay nice and cool while exhaust valves get hot and wear? Not sure what kind of engine you are working on but both valves are in the combustion chamber and exposed to the same heat. To my knowledge they are both made of the same material. Could you possible explain a little further? Im not sure I see your point...

Always good to hear your sage take on areas of interest to this sailor.

Would it be a fair statement that exhaust valve wear (uneven) would be reflected in less fuel economy? Any other symptoms you can think of appreciated big time...............

(Just like your take on Iridium spark plug longevity: thanks again)

all the best, ez....

aranoid: Not sure if serious. sarcasm is new to the south, please forgive me.