Audible Valve Clearance Check?

[heypete]

My 2006 Toyota Camry is coming up on it's 60,000 mile service interval. The only thing of note for this interval is that the manual states the valve clearances should be checked.

I was talking to my trusted local mechanic about this, and they said Toyota recommends an "audible" check, rather than actually taking the valve cover off and checking the clearances with feeler gauges. While I trust the mechanic's word, I was a bit surprised -- it seems strange to me that one would be able to get any sort of accurate assessment of the state valve clearance (other than being grossly out of spec) simply by listening to the engine.

The Haynes manual details the procedure for taking the valve cover off, rotating the crankshaft to TDC for each cylinder, and measuring clearances with feeler gauges. Nothing about audible checks.

Any thoughts on this "audible" checking? Is the mechanic right? Is my skepticism worthwhile, and should I take the cover off and check things with feeler gauges?

 

[ahoier]

call up a dealer or 2 (maybe 3....) within your area and get some input. Each shop will likely have different procedures, but yea checking clearances simply based on hearing seems kind of strange, then again, they are trained to know that kind of stuff; but say there is a clearance problem, they will likely have to tear it apart anyways to see what's going on inside anyways, right? So why not just get it done right?

I mean, anyone can do an "audible" check, simply comparing the sound the engine sounded when you got it to how it sounds now

But maybe they have more suited equipment to run the sound through to actually check it. Likely they'll use a stethoscope type deal-io to listen to the internals.

 

[Scdevon]

Your 2AZ-FE engine uses lifters which resembles a "bucket and shim" design without shims. If the clearance is off, there are 32 different sizes of cam followers which can be swapped to correct the clearance.

60K is WAY too soon to worry about the valves in this engine. My 1989 4AFE Corolla has 228k miles on it and uses a similar set up. The valves have never been adjusted and they are still in spec.

It is an extremely stable and reliable valve geometry design.

 

[ET16]

I seem to remember this method for push-rod engines with hydraulic lifters.

 

[bepperb]

Unless there was a noticeable tick, I probably wouldn't do a valve lash measurement. And I didn't. So, I guess that qualifies as an "audible check."

Really, the valve adjustment on the 2azfe is a pain, not necessarily to do but to get the right sized buckets for. Sure removing the cam is a pain, but on a 4 banger everything is right upfront. The check is probably pretty easy and straightforward.

 

[heypete]

Originally Posted By: Scdevon
Your 2AZ-FE engine uses lifters which resembles a "bucket and shim" design without shims. If the clearance is off, there are 32 different sizes of cam followers which can be swapped to correct the clearance.

60K is WAY too soon to worry about the valves in this engine. My 1989 4AFE Corolla has 228k miles on it and uses a similar set up. The valves have never been adjusted and they are still in spec.

It is an extremely stable and reliable valve geometry design.


That's good to know.

It's not that I'm worried about the valves, as I've been quite religious about oil changes and other maintenance, so I doubt they'd wear much due to lack of oil. I'm just going by the manual, which says "Check valve clearance at 60,000 miles" (or some text to that effect).

I'll call around and see what other shops have to say about it.

 

[mechtech2]

If someone is very familiar with a certain engine, an audible check may be valid.
If this is performed, do not pay for a check!

Even in Pro Football, sometimes the quarterback calls an audible, apart from a plan.

 

[nthach]

FWIW, I wouldn't worry about valve adjustment on a Toyota engine until you're well into the 200K range. Solid lifters tend to keep their adjustments relatively stable.

 

[Smoky14]

Let me get this straight....your ear is as accurate as my feeler gage.

 

[Vikas]

Originally Posted By: mechtech2
If someone is very familiar with a certain engine, an audible check may be valid.
If this is performed, do not pay for a check!


That's it! Most of the 30K service is "inspect/check" and does not even involve opening anything and the sucker (I mean the customer) still pays lots of money to be told that everything is fine!!

- Vikas

 

[KrisZ]

Agree, all those dealer services at 30k and 60k are nothing than an oil change and a bunch of inspections, that probably doesn't even get done, just a tick in the check box. Save your money and if you actually want to check the valves, do it properly with a feeler gage.

 

[mechtech2]

Smokey - You and I would check them, of course.
But if you see the same engine day ofter day, you can tell by smell and sound if it is normal.

In the old days at the FBI, agents were sent to banks for week to handle and familiarize with all sorts of paper money. They got a 'feel' for what was legitimate, so a counterfeit was evident to them.

[It is way different now, of course.]

 

[stranger706]

My Mazda manual says the same thing - Audible valve inspection is due at 75,000.

I listened and it sounds normal. I do a quick underhood inspection with the engine on almost every week though so it would be obvious to me if something was off.

 

[Smoky14]

In my experience so many valves get tighter because of high cyl temps allowing the valves to seat further into the head. A loose valve clearance is easy to hear not too easy to detect tight valves by sound especially in bucket with shim adjustment.

If it's my car the feelers come out and the VC comes off.

 

[ledslinger]

My wife and daughter have 1999 and 2001 4 cyl Accords. The manual says to adjust the valves if noisy. They weren't noisy but I checked them when I did the timing belt at 105K miles. Each car required 2 or 3 of 16 valves be adjusted, and they were only off .001".

Put your ear to it and if it sounds good leave it alone.

 

[Trav]

Let just hope none of these engines develops valve seat recession.That will be the next class action law suit.
I want to meet the mechanic that can "hear" tight valves.

 

[swalve]

I would think that if the valves somehow had gotten too tight, there would be performance indicators. Loss of compression, low MPG, high unburnt HC, etc. If the car is in otherwise working order, an audible check should be fine in 99% of the cases.

(Why doesn't everyone use hydraulic lifters nowadays??)

 

[berniedd]

Originally Posted By: swalve
I would think that if the valves somehow had gotten too tight, there would be performance indicators. Loss of compression, low MPG, high unburnt HC, etc. If the car is in otherwise working order, an audible check should be fine in 99% of the cases.

(Why doesn't everyone use hydraulic lifters nowadays??)


Unfortunately, for some engine designs, there's already engine damage when you get these symptoms. Example: the first generation CRVs are exceptionally prone to early valve seat recession, causing valve tightness and eventually, valve burning. That's definitely not a cheap engine repair cost. Yet, many manuals for these cars incorrectly said: "Adjust the valves when they are noisy, or do the valve adjustments at 105,000 km." But noisy valves are valves that are just too loose and really don't make for engine damage!! Tight valves don't make normal noise. As Trav said above, I want to meet the mechanic that can "hear" tight valves.

 

[mechtech2]

Too tight is worse than loose, for sure.
I really haven't seen a burnt valve in a while, though.
Or one that is not seating because of being too tight.
Only if someone was playing around and did not set it right.