Special tool, on Amazon:
http://www.alltradetools.com/EN-938.htm

Feeler gauge set, $2.99 at Harbor Freight, similarly priced at Pep Boys and couple of bucks higher at Sears:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=32214

The main concern is with too tight a clearance. When there is insufficient time of contact between the valve and the cylinder head, the combustion heat doesn't dissipate from the valve as quickly. The heat build up "burns" the valve.

Loose clearance simply results in a loud valve train and usually people respond to this. So it's not as big of a deal as a tight clearance.

Toyota used to recommend 60K mile check/service. But I guess marketing department done away with that. People said they're not expected to change much. So dunno here.

When in doubt of prior maintenance (especially oil changes), you might want to check. At least that will give you a data point.

 

The main concern is with too tight a clearance. When there is insufficient time of contact between the valve and the cylinder head, the combustion heat doesn't dissipate from the valve as quickly. The heat build up "burns" the valve.

Loose clearance simply results in a loud valve train and usually people respond to this. So it's not as big of a deal as a tight clearance.

In addition to what John said;
You can't hear the valves which are too tight (have no clearance). The Exhaust valve being held open, will overheat as a result of no contact with the head for cooling and those hot exhaust gases whistling past it. The end result is a burned valve.
- A burned valve is no compression in the cylinder. . . From there it all goes down hill. Gas mileage, failed emisions, fouled spark plug, plugged cat convert for trying to burn raw fuel. . . .
_ The intake being held open will stop the show as combustion chamber gases will enter the intake plenum and impact all cylinders. It will run bad!

I did a write up on the counterpart (the V6). Mine were to loose and required adjustment. An adjust made with a custom part as Toyo doesn't make a shim thick enough to correct the condition.
Again, not that it was hurting anything, but the noise was annoying. >>Link>> http://www.toyotanation.com/forum/showthread.php?t=118997

 

thanks JohnGD.

i was reading Haynes and just realized that "adjustment" actually requires removing and replacing some shims with new ones of exact (different) thickness, so i guess i will leave it to a pro. not as easy as i thought, too much hassle for me with this task.

do you know how much a shop can charge for valve clearance adjustment ?
what is the Toyota recommended valve clearance check/adjustment intervals nowadays ? i feel like it's supposed to be done to get the engine run as it used to in past (now is louder). ATRA shop i visited gave me a business card of another shop doing engine repairs, i might just call them to see how much they charge for it.

in case i replace the valve cover gasket only and then decide to adjust valves at a specialized shop, will they have to use a new gasket again ?

thanks.

 

IIRC used to be about $300-400 for the adjustment. Knowing they even measured anything would be tough. You should require them to write down all clearances measured.

Measuring the valve clearances is the easy part. With the valve cover off (say, replacing the gasket), it would be a good time to do this. However, you need to get the front onto the stands so you can rotate the crank. Of course, that means an 18" or 25" breaker bar (no need to remove plugs), as in: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=30395

And if you don't have 1/2" sockets, this was on sale during the holidays for ~$20. Not sure how the "new" cheap 14" breaker bar will work (used to be 18" which I have, along with their 25" one).
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=45467

I would measure the clearances while the cover is off. If all are within spec, put the new gasket on there with dabs of RTV (Permatex Ultra Grey, or just sensor safe high temp Red RTV, $0.99 at 99-cent stores). Otherwise put the old one back and let the shop handle the rest, tell them what you measured so they don't toy with you.

Found this at 99-cent store, used only various Permatex RTV myself however:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90026

If you do let us know what you measure. Yeah, just more tools all the time. I would be particularly interested what you measure of the exhaust ones.

 

yeah i guess i can at least take the measurements myself. will get the feeler gauge and breaker bar from HF tomorrow if time allows (visiting muffler shop in morning first). i'm very curious as well what the valve clearances are at 70k miles. when it was at 35k it was almost dead silent with hood closed.

in my ignorance i didn't think of the fact that rotating camshaft (hope this is the one, easiest to access) makes the wheels to spin too haha :facepalm:.
good i've got the stands and a jack from past adventures. it sounds like i'm only waiting for a lovely warm Spring weekend to get this done (plus seafoaming and 2 consecutive oil changes before and after).

i've got only 1/2'' deep socket set (metric) and a 1/2'' click-stop torque wrench, hoping it would fit as rest of my tools are 3/8''.
i'm planning to use my 1/2'' torque wrench instead of a breaker bar. it should do (i hope), i use it for all tasks requiring lots of force wherever my 1/2'' deep sockets can fit.

 

Valve clearance can be tough, because of the shims and also there is some math involved, with regard to shim thickness, valve adjustment, etc. It's not like old days and easier way of doing a valve clearance adjustment.

 

Show of hands -- does anyone actually do this?

Years and years ago, I used to check the valve clearances on Toyota engines. Never found anything needing adjustment, so I finally decided I had better things to do with my time.

 

Show of hands -- does anyone actually do this?

Years and years ago, I used to check the valve clearances on Toyota engines. Never found anything needing adjustment, so I finally decided I had better things to do with my time.

If you look at the design of the valve train, I'd expect some will get tight and cause burned valves. So checking is an once of prevention.

Typically those valves beating on the seat with 150 to 250lbs of force lead to the valve seating deeper into the valve seat. Should this occur, it could lead to the valve being held open and subsequent burned valves.

He alsmost has all the tools, so I'd check it.

=======================================
Thread jack????

Personally I wouldn't recomend using your torque wrench for anything other than measuring torque (maybe I read that wrong?). I have spendy Snap-On one and wouldn't use it for daily use (ratchet) or breaker bar as it WILL degrade its performance!

I doubt a HF torque wrench holds 5% tolerance at full scale let alone 1/4 scale so I'd buy a breaker bar.

Lets say full scale is 250ft/lbs
250f/lbs * .05 = 12.5f/lbs which would be where its most accuarate (near the end of the scale. So thats 250 +/-12.5ft/lbs

At 1/5 scale or 50lbs, I'd guess it heads towards 8 to 10% accurate. (45 to 55 when set at 50lbs.

$250 Wrench
Accurate to 2% of the reading from 20% of full scale to full scale.

$500 Wrench
Torque accuracy ±2%CW, ±3% CCW, 20% to 100% of full scale.
This says that from 20% to 100% of its range they guarantee it (50lbs to 250lbs, it will deliver ±2%CW).
OR - at 50 you'd get 49 - to 51, at 100 you'd get 98 - 102. That's fine by me! But thats a $500 wrench!

Personally I can't imagine a 30 dollar knock off having any kind of repeatablity. That is, it might be +/-5% new, and then decline rapidly if left loaded at 100Lb/ft like the guys at the tire stores do or thrown about. Most cheap k/o's are not meant to be reveresed and used as a breaker bar.

Something to think about!

 

i have 172k miles on my camry and i have yet to perform this.

 

thanks for your opinions guys!

in my case a have a ticking noise coming from crankcase - left side, cyls 1&2. that's why i guess there is something out of adjustment. first thing coming to my mind was valve clearance. it started doing it let's say 8 months ago, it's not getting louder, it's just there (wasn't in past). it also makes my exhaust tick at rear end (same sound carried through metal parts).
ATRA techs confirmed this when i was checking tranny at their shop and gave me contact with another guy doing this kind of work.
once i know measurements i will know if i want to spend $400 for the valve clearance adjustment on my 5sfe.

as per using torque wrench as a breaker bar. i never assumed a $15 wrench to be precise. anyways how about i set the torque to let's say lowest 20ft-lbs and let the wrench body (not the spring) carry the load when i use it as a breaker bar ? IMO it shouldn't hurt it in any way... just something i read on this forums. let me know if it makes sense to you.

 

Might as well do valve seals while you are in there.

 

thanks Kenny, but i don't want to spend thousands on this car. just want it to run more quiet again, i can live with that occasional puff of white smoke from exhaust hehe, it's a 10yr old car, doesn't bother me very much.

 

As above, if you can pull the plugs, valve cover, and have means to turn the engine over, grab a feeler gauge set and that gasket and you can have a couple hours of fun!

You turn the engine over to seal the valves (cam lobe away from lifter) and check the clearance. It sounds like you could do this if yanking the valve cover off is no big deal to you. It'll give you peace of mind. If it turns out not to be the valve hopefully lead you to what does make the noise.

FYI: I have found that Toyo does not stock all the shims. Hence there could easily be a need to pull the valve cover, take measurements, pull out shims which need to be measured (if clearance is out of spec) and then put it back and drive it until the part(s) comes in. Its not like it will be any worse in a week. All you need to pop the shim is a BIG screw driver with a nice flat end. With a little finness, you depress the valve spring, pop the shim and measure the shim. One person can do it. It will take some grunt power though!

Try the back side of the V6, real FUN!!! {NOT}
you look at this? http://www.toyotanation.com/forum/sh...d.php?t=118997

As for the wrench:
Nothing personal. Just trying to inform people. I'd get a long handle ratchet and save my special tools for when I need them tho. . .

 

one thing that i noticed on my car is worse gas mileage THAN in past. it's not a big deal, difference of maybe 2-3 MPG down throughout 2-3 years. just trying to understand how it all works and find a reasonable explanation for all of this.
despite full tune up, using fuel additives, cleaning IAC, replacing many gaskets I fail to regain its once superb gas mileage. perhaps it all changed with the drive style of my wifey ... she becoming a racer maybe hehe :lol:

besides i'm learning a lot when playing with this car (and my old V6). i did full tune up on that V6 myself including all filters and replacement of gasket under the front valve cover and serpentine belt (very easy on this model), also did a repair of leaking oil pressure switch on this one.
i haven't done the rear bank yet as it requires unbolting and moving aside p/s pump and some other stuff. besides my back hurt enough when i was replacing spark plugs over there (from top)... hehe :facepalm:

what torque force is required to turn the 5sfe engine manually (for valve clearance measurements) ? and just to clarify, what do i turn actually, camshaft (the one sitting in crankcase) ?

I also see that actually not many people do the valve clearance adjustment. some of you do it very rarely like Mike 173k miles and found nothing wrong. hmmm... i think i will just do it for fun then.
another reason i wanted to make sure i know why cylinder 1 (mostly it comes from there) makes the tick noise. if i found it out of spec, i will have peace of mind and think about fixing it maybe (not 100% sure, it's pricey).

 

I noticed your long term fuel trim is +14.8%. So the oxygen sensor/ECU thinks it's running lean and adding extra fuel.

There may be many reasons, air/vacuum leaks, plugged injector, etc. The following is an interesting article that you might want to read:

http://www.motor.com/magazine/pdfs/092006_11.pdf

 

Yeah I dont think anyone does this...ever. Your average joe mechanic has never even does this.

Id rather spend the 300$ on something worthwhile. The adjustment would probally not even done by the mechanic and the money would just go to waste.

 

If the tick is at crank speed (every rev) equals => bottom end.
If the tick is at cam speed (1/2 of crank speed) then it sounds like your mystery tick is the valve(s) in the top end.

My valve cover was seeping oil and it had noisy little tick from one valve under that cover so I checked them and 1 of 24 was out of spec.

To Carus point, I bet many a mechanic has claimed free $$$$ by checking them and finding everything OK and/or saying they were checked and rolling the dice. Most of the time, its fine. Just not all the time.

 

thanks 73sport!

i'm not quite sure how to tell the speed difference, but to my untrained ear it sounds more like 1/2 the speed of crank. don't tell me how i can tell it on this car, it's just a feeling in guts because everything runs fine in general.

all i can say is in past my parents had bad lifters in '97 Alfa Romeo 1.4L long time ago and it sounded different (the higher revs the louder noise, and it was at faster pace at idle) - that engine sounded like a mad Chinese master chopping chef

i'm pretty sure it's the other one in my case (much slower pace). Then I would guess based on above it's one of valves at top end on cyl 1 (or maybe 2, as seeping oil is above this one).

for now it will have to wait, as 10-day weather forecast sucks. i will get back to that in mid-March probably, if that is when the Spring comes back to Jersey this year. it's something i don't need to rush for, it doesn't get worse at all.

It will be an interesting experience for me and also i really want to know more
at some point I may even consider fixing it myself if the problem is in deed about only 1 valve and 1 shim. one thing for sure, i'm not planning any repairs on valves before measuring them first. meaning I will open that crankcase at least once. i'm not very eager to pull $400 out of pocket for fixing something that is rather esthetic only.

I read your thread about your V6 and fixing ticking valve. good job you did with it

 

If you're doing your own valve cover gasket, it should be relatively easy to check the valve clearances at the same time. That's something I think you should be able to do. And then only pay to replace if they're out of spec. I'd worry more about tight clearances than loose (typically noisy).

Besides the feeler gauge set ($2.99 or so), definitely a longer breaker bar (like the HF 25"). I wouldn't recommend using an adapter to use 3/8"-drive sockets. You may be pushing their limits (good to about 80 lb/ft+safety margin).

 

thanks JohnGD. i will probably get that 25'' breaker bar if turning the engine turns out to be a problem for a 1/2'' torque wrench plus 1/2'' deep socket.

will do some reading on the article. interesting point about ECU thinking its running lean in long term. it might very well explain that missing 2-3 MPG from average efficiency. after seafoaming the car and cleaning IAC one more time (seafoam deep creep this time) i will reset the ECU. i hope seafoam will take care of fuel injectors.

thinking about checking for air/vacuum leaks too. i assume i should look for a hissing noise anywhere close to hoses. or maybe i should unplug the vacuum ones and plug each one to a vacuum pump and see if they hold ?

i was thinking about oxygen sensors too, but from every possible test via obd2 i've run all sensors come up OK every time (no error codes either). you think one of them started acting up ? which one might be the most suspicious ?

 

Generally speaking torque wrenches shouldn't be used as breaker bars. I know some older HF ones can be used to loosen in the counterclockwise direction, but I still use a breaker bar. However, in the clockwise direction it's measurement only.

I'm not sure about newer HF torque wrenches. At least my Danaher-made ones (Kobalt, Craftsman) are measurement in both directions. These come in handy for left hand threads.

I think you need to turn the engine crank clockwise.

As far as the long term fuel trim, the article has an interesting method of doing injector balance tests. That shows how a plugged injector can cause extra fuel to be injected by other injectors and pretty much wasted.

If your accelerator cable is properly adjusted and IAC is working properly, and your idle RPM is about 1000, then there is most likely false air entry.

If you hooked up the MityVac to the EVAP port on the throttle body (the hose from the EVAP line), you should see 17-22 in/Hg. However, things may be in range and you still can have a vacuum leak.

I would worry about the simpler things before going after sensors. Especially when you have < 100K miles. 100K miles is a good threshold to "consider" replace them.

 

thanks, i got the point about torque wrench vs breaker bar. you guys all are very convincing, 3 people saying same can't be wrong hehe. at least I won't destroy my wrench, will be getting a breaker bar.

as per ECU scans with OBD2 tools. i am worried about one thing, it shows zero errors so no matter what could be failing it isn't failing enough to trigger any darn codes. both fuel injectors and oxygen sensors are supposed to trigger MIL (CEL or whatever). even too low or too high EVAP pressure is supposed to trigger something or at least fail an OBD2 EVAP test (all passed including EGR, oxygen sensors and others).

now, as you noticed I have a huge positive adjustment to long term fuel trim (wasting fuel), it makes me feel that something is really fooling the ECU, just not enough for it to alert the code. I have read somewhere that fuel injector will trigger a code if its short or long term adjustment goes beyond 10%. I have almost +15% LTFT and still no codes, WTH ?

I just hope it all gets better after sea foaming everything.

I will try in close future hooking up mittyvac to evap to measure pressure and see if that's in range you mentioned. besides that and listening for any hissing i got not much idea of other checks i can do ... i have to admit i'm kind of tired (only sometimes fortunately) of searching for needles in a haystack.

can a faulty PCV valve grommet cause that false air intake/exhaust ? i didn't replace it yet, might do that when removing the valve cover. also i used a cheapo PCV valve from AZ, it has some rust on its metal piece already (6 months old).

EDIT:
this will be my toyota parts shopping list for valve cover job (toyotapartsoutlet.com pricing):

(PCV) "valve sub-assy ventilation" $6.06
12204-74030

(PCV) "grommet for ventilation system" n/a
90480-18001
superseded by 80480-7602671, not in stock

4x "washer seal for cylinder head cover" $3.03
90480-30025

"gasket cylinder head cover" $9.12
11213-74020

since those are not very expensive i might get them over the counter from dealership. i just hope they have the PCV grommet as no online retailer carries it. also original part was superseded by new part, perhaps there was something wrong with it.

 

OBD-II set codes only if it detected emissions 1.5x the US federal limit. Therefore, if the engine is polluting 1.49x, technically you won't see the MIL light.

And it's possible that no MIL is set when an oxygen sensor is at fault. That's why some people with the P0420 code needlessly replaced catalytic converters.

According to the Motor.com article, +/-5% LT/ST fuel trim is OK, but yes, >14% you kinda want to look into. Not sure truly a fault however. I think you have to peg max both LT and ST to set lean or rich codes?? Not really sure.

No, PCV valves are so simple they usually stick and not let air pass. I've been using Fram on various makes without problems. It's the PCV grommet that you need to make sure seals right. Do you see oil around it? Hope not. Should be dry and clean. A good salesperson (or one low on the monthly quota) will typically bring out the grommet with the valve. They should be replaced together, like thermostat and its gasket.

Don't forget the RTV for the valve cover gasket, even if you only need a few dabs. (What a waste as these tend to dry out, even if you squeeze out a small sacrificial amount before capping).

Don't feel burned out. Hey, maybe we are to blame. :naughty: Your car used to work flawlessly before we started talking, right? :lol:

as per ECU scans with OBD2 tools. i am worried about one thing, it shows zero errors so no matter what could be failing it isn't failing enough to trigger any darn codes. both fuel injectors and oxygen sensors are supposed to trigger MIL (CEL or whatever). even too low or too high EVAP pressure is supposed to trigger something or at least fail an OBD2 EVAP test (all passed including EGR, oxygen sensors and others).

now, as you noticed I have a huge positive adjustment to long term fuel trim (wasting fuel), it makes me feel that something is really fooling the ECU, just not enough for it to alert the code. I have read somewhere that fuel injector will trigger a code if its short or long term adjustment goes beyond 10%. I have almost +15% LTFT and still no codes, WTH ?

I just hope it all gets better after sea foaming everything.

I will try in close future hooking up mittyvac to evap to measure pressure and see if that's in range you mentioned. besides that and listening for any hissing i got not much idea of other checks i can do ... i have to admit i'm kind of tired (only sometimes fortunately) of searching for needles in a haystack.

can a faulty PCV valve grommet cause that false air intake/exhaust ? i didn't replace it yet, might do that when removing the valve cover. also i used a cheapo PCV valve from AZ, it has some rust on its metal piece already (6 months old).

EDIT:
this will be my toyota parts shopping list for valve cover job (toyotapartsoutlet.com pricing):

(PCV) "valve sub-assy ventilation" $6.06
12204-74030

(PCV) "grommet for ventilation system" n/a
90480-18001
superseded by 80480-7602671, not in stock

4x "washer seal for cylinder head cover" $3.03
90480-30025

"gasket cylinder head cover" $9.12
11213-74020

since those are not very expensive i might get them over the counter from dealership. i just hope they have the PCV grommet as no online retailer carries it. also original part was superseded by new part, perhaps there was something wrong with it.

 

haha :lol: yeah, you did this!

but honestly, without help of people on this forums i would still know shit about cars (changing air filter and topping up fluids was all i could do before haha). besides i like the collection of tools i got throughout those adventures hehe
all i need is to avoid american cars as torx bolts on buick give me shivers...

i'm gonna use oem PCV and grommet just be sure. old grommet was kinda a little loose, maybe not enough to pass oil (no signs), but i think it might pass some air in/out and maybe fool the operation of PCV because of that, just my understanding (correct me if wrong).

also i think seafoming and using some real fuel injector cleaner like Chevron Techron concentrate (now on sale buy 1 get 1 in AAP) could heavily impact fuel trims (as well as air/vacuum leaks would). will do those first and take some more readings at idle and driving. i'm planning some real tortures for this car once the weather clears out (and snow melts down) on some weekend. then will do the valve cover plan.

 

Ouch! Ouch! :lol: :lol: :lol:

Sure, when in doubt just go with OEM. You don't see oil around the valve cover gasket do you? That would be a sign of leaks too. You might want to wait on the PCV/grommet until after the SeaFoam.

And I guess you'll get to check on changes in various ECU parameters with your scan tool. :thumbsup:

 

setting up new fuel trims thread. this one was supposed to be about valve clearance adjustment
http://www.toyotanation.com/forum/showthread.php?p=3099922#post3099922

also local HF was out of stock on feeler gauges and 25'' breaker bars. i didn't take the 18-3/4'' breaker bar as it seems to be smaller than my 1/2'' torque wrench which i still intend to use if cannot get a cheap breaker bar.

 

if things go right maybe next weekend i will have time (and all parts + tools) to open the valve cover and take valve clearance measurements.

what socket size is necessary to attach to crankshaft bolt? i understand that i would have to get there from bottom or through passenger wheel well as there is not enough space from top.

 

I have the same thing happening! The cylinders one and two are both ticking. #1 actually moves my plug wire when the motor is one! Keep us posted

 

if all goes well tomorrow I will take the fight to valve cover and valve clearances. i'm a little thrilled about turning engine by hand, so would like to confirm 2 things, before i start.

1)
what socket size fits the bolt in crankshaft pulley ? will a deep socket fit or i need the standard (low profile) one ?

i think i found the answer in gen1&2 section (19mm socket):
http://www.toyotanation.com/forum/showthread.php?t=236678

2)
Haynes states clearly that best is to use large socket and a breaker bar to turn crankshaft by bolt in the middle until "v notch" aligns with "0" timing mark. that will put cylinder #1 at TDC, i will have to confirm with compression gauge if that is on compression stroke or exhaust stroke, no problem here.

Now let's say I find it easily and take measurements of all valves that i can measure with cyl #1 at TDC (IN 1&2 and EX 1&3).
What do I have to do to put cyl #4 at TDC on compression stroke from above, so i can take measurements of the rest of valves (IN 3&4 and EX 2&4) ?
1 full (360 degrees) crankshaft turn will do it ?

if I put cyl#1 at TDC on exhaust stroke by turning crankshaft 360 degrees from above will this be also a cyl #4 at TDC on compression stroke ? this one is unclear to me yet. thanks.

EDIT:
never mind about q no.2

Haynes explains it well, misread it before.

After the number one piston has been positioned at TDC on the compression stroke, TDC for any of the remaining cylinders can be located by turning the crankshaft 180 degrees and following the firing order.

firing order for 5s-fe is 1-3-4-2, so to put cyl# 4 at TDC c.s. i in fact need to turn crankshaft further 360 degrees just as i was suspecting.

 

valve clearance measurement results (completely cold engine) in millimeters (sorry this one's native to me):

cylinder 1
INTAKE 0.23 and 0.25
EXHAUST 0.30 and 0.30

cylinder 2
INTAKE 0.28 and 0.25
EXHAUST 0.33 and 0.33

cylinder 3
INTAKE 0.25 and 0.28
EXHAUST 0.30 and 0.30

cylinder 4
INTAKE 0.28 and 0.28
EXHAUST 0.33 and 0.35

norm per toyota emissions sticker for my car (on cold engine) intake 0.19-0.29mm and exhaust 0.28-0.38mm

that means all are in norm on 10yr old engine with 72k miles, nice

here are pics of my '00 solara's top of cylinder head (1 sea foam treatment 2 weeks ago).

note how big chunk of RTV the factory used on timing belt side. i actually had to remove the excess of old hard RTV from all points of application. they used to much IMO, i hope none of it got broken off and sucked in by oil pump.

 

note how big chunk of RTV the factory used on timing belt side. i actually had to remove the excess of old hard RTV from all points of application. they used to much IMO, i hope none of it got broken off and sucked in by oil pump.

Just my 2 cents:
It looks like the cover was off once and no one removed the original "White" looking sealent (no stained with oil) and simply added a new blob! Which as you point out is Excessive and could clog a galley and result in damage to an engine if it were to break free... It is a picture so I could easily be mistaken, but that how it looks. How old is this machine? Is there no trace that it was ever apart before?

 

this is a 2000 camry solara se 5s-fe engine. as far as i know the valve cover was never taken off by anybody as previous owner did not touch the engine and i did it for the first time ever. old gasket was baked and looked like OEM (10 yr old). the RTV under gasket came off with it, the excess stayed.

BTW, if anyone missed, all valves are in specs, not perfect as some of them are close to upper limits, but stilll ... in specs for now. the louder engine operation ("tapping") i was reporting recently, i started noticing after switch to synthetic 5w-30 oil (any kind) which i use since July '09. in 1000 miles i'm switching back to dino and will do some auto-rx clean up on it. car was "sea foamed" once in near past using dino oil for that procedure and i noticed it runs quieter on it. again started running louder once i poured in synthetic (valvoline synpower now, running 2.5k interval for cleaning purpose).

 

If your Auto-RX is like the Rislone product, it will thin out your oil viscosity a bit. So even your dino oil might continue making the ticking noise you have come to hear due to the additive product reducing the viscosity. I know the Rislone additive I used reduced the running oil pressure on my 5S-FE about 5-7 psi (which I used to help clean out some sludge buildup). I'm done with that process now. I have also noticed a slight increase in ticking sound with synthetics over dinos.

PS: Your original post question: Whenever I have a need to remove the valve cover, I check for valve clearance. It is just a routine for me. I have never had to adjust anything yet, except once. And that was when I was doing a timing belt change and I had a small oil leak at the headgasket anyway, so I knew I was going to pull the head off. Sure enough, one of the exhaust valves on a 4A-FE Celica engine was just a little tight. The machine shop I took the head to (to get the base machined flat and to install new valve seals) simply took one small swipe on the top of the tight (long) valve to take a little material off, and when it was reassembled with the same shim, it was back in spec. Those guys knew what they were doing. And if any valve had too much clearance, they said they typically lap the valve in the seat just a bit, which has the same effect as putting a slightly thicker shim in. But they also said they rarely see valve adjustment requirements in older Toyota engines.

 

thanks for your opinions guys. it shed some more light. seems that is no more a problem and is quite common for those older engines to tap a bit with synthetics and still run great which makes me smile

93celicaconv, thanks for info on cleaning additives, now it makes sense to me why those same viscosity synthetic was appearing to me as thinner than dino. i'm not sure about auto-rx vs rislone, probably pretty much similar stuff, will keep in mind the "tapping" effect.