Yota valve adjustment.

[simple_gifts]

My !echo! is approaching 150K and now has a "tick" at startup in cold weather, especially under load. I have the factory manual and a valve adjustment seems to be a three ring circus of crank rotations, open and closing access doors, removing cams and mic'ing each solid lifter and installing new lifters with the adjustment "built in" to each new lifter.

Has anyone done one of these; I'm not going to try, I'm not even sure if I trust a dealer to do it. Should I wait until the noise is constant even after warmed up?

Perhaps someone has a suggestion about the source of the noise if I am off base. Car has had diet of Mobil1, Redline, Amsoil since 1200 miles and filler hole is "as new"

 

[jamesn]

its really only an annoyance. is it really worth the trouble at this point? this car might very well go another 80k miles without it getting any worse.

call the dealer and ask them how many hours at the shop rate it is listed as taking before you make up your mind. you might very well be shocked at the time it is supposed to take a professional mechanic to do the job. get a price estimate.

if you live in a major city, there might ery well be a toyota specialist shop or at the very least a import shop that will do it.

 

[chrome]

You might want to be certain that you are having a valve clearance issue. Cam over shims generally go a long way before requiring any attention.

You mentioned a tick that is especially prominent under load. That could be a small leak at the exhaust manifold or nearby fittings.

 

[Quest]

solid shims on a bucket style valve setups in Yotas seem to be the norm these days,so don't be surprise (chrome take notice) if it requires a bit of re-shimming over time.

If you are a weekend/amateur DIYer whose familiar with valve adjustments, you shall first contact your neighbourhood Yota parts dept and double-check (more like double-chat) with the service guy to ensure that they carry those shims with them, and if not, they can bring them in in a relatively short period of time.

Next, with the engine cold, you then pop the valve cover and then take a reading of all the valves (get a notepad and take notes on all the valve orientations and their corresponding valve clearance readings) using a high quality thickness gauge.

NExt, you get a valve adjustment tool and then pry/prop those shim pucks loose one by one and read their markings and then take note. If the markings (thickness of shims) are worn, get a micrometer and then measure it.

You then go find a thickness chart (usually, your factory svc manual has that chart within) and then carefully calculate the needed thickness of the shim (to get it back to spec) and then write down the thickness number. Pop those shim pucks back in where they belong and put the cover back.

Bring the list to your Yota dealership and see if they can get them in for you quickly.

repeat the steps of removing valve cover, pop the individual shims and then replace them with the obtained one. Sometimes, you may be able to swap one of the used one off of a particular section and then use it in another one, to save mullah.

carefully, shim each valve to ensure they are within spec again.

replace the valve cover gasket with a new one, put everything back where they belong and then be happy that the ordeal is over.

Q.


Repeat the steps

 

[tom slick]

ticking under load is usually an exhaust leak. they can sound exactly like valves ticking though.

 

[mechtech2]

Right.
A valve doesn't tick under load. It doesn't
know if there is a load on the crankshaft.
You can stuff a rag into the exhaust pipe and start the car for a short while. Rev it up and listen for where any leaks are. You can open the hood and operate the throttle from there while listening.

 

[Chris142]

As they age the clearance gets smaller, not larger.

 

[jamesn]

Originally Posted By: Chris142
As they age the clearance gets smaller, not larger.


huh? run that by me again.

 

[Gary Allan]

Quote:
replace the valve cover gasket with a new one, put everything back where they belong and then be happy that the ordeal is over.


It does have all the appeal of a colonoscopy.

 

[tom slick]

Originally Posted By: jamesn
Originally Posted By: Chris142
As they age the clearance gets smaller, not larger.


huh? run that by me again.


as valves wear at the face/seat they recede into the head, making the clearance between the cam and follower/lifter/shim smaller. it makes diagnosing a "sucked valve" really easy.

what most people think of as "adjusting the valves" is actually adjusting the cam to follower. the cam lobe or follower/shim wears and the clearance grows.

 

[mechtech2]

Nowadays we have very hard valve seats and valve faces.
Wear is largely on the cam, valve stem, pushrod, or lifter/bucket.
Clearances get larger in my experience.
A little loose in better than tight. Sure, maybe a bit more noise, but no real concern or harm from it.
Adjusting shimmed buckets or replacing buckets is a royal pain, so don't be too picky when you check the clearances.

 

[Drew99GT]

Unfortunately, your Toyota does not have shim over bucket; it has the new system where you have to actually remove the camshafts and replace the lifters. Pretty involved process requiring great attention to detail. Tenfold harder than shim over bucket like my 94 Corolla.

When I did my valves last year, 2 were a hair lose, and 2 were a hair tight. Tighter is the problem because if they get too tight, the valve won't close all the way and burn up, especially exhaust valves and tightness usually happens to exhaust valves.

If it only happens in the morning, it really could be piston slap. If you're the least bot technical; ie, if you can pop off the valve cover and turn the crank with a ratchet, you can at least measure valve clearance. As long as none are excessively tight, I'd call it a day.

 

[kschachn]

I have both a Sienna (1MZ-FE engine) and an ECHO, I've adjusted the valves in the Sienna but not the ECHO. When I did that on the Sienna it had over 160,000 miles and like you, it had seen a steady diet of M1 and Syntec which was changed approximately every 5000 miles.

To say I "adjusted" the valves isn't correct, I only measured them because every last one was perfect. They were all nearly at the maximum clearance (would allow for maximum wear yet) and none needed new shims. So if your situation is similar I seriously doubt it is the valves.

On mine I also heard a ticking sound. On the Sienna it turned out to be a worn timing belt idler pulley, but since the ECHO has a timing chain that can't be your problem. If I were you I would go to the dealer and let them listen to the noise for you. At my dealer, this is what I did and he correctly diagnosed the problem - for free. I bought the new timing belt, idler and tensioner pulleys from him and the noise is gone. I guess it goes to show that a lot of different things might be making that noise.

The ECHO engine (1NZ-FE) is noiser than 1st-gen 1MZ-FEs due to the variable valve timing mechanism. It may also be a component on this system.

 

[mechtech2]

Also, temperature makes a big difference in valve clearance measurement.
I check them stone cold because it's the most consistent way .