I have been informed of a quik-N-dirty valve adjustment procedure by a "ASE Master Mechanic":
Comprising a no-swap-out of the adjustment shims, you measure the clearance and fill in the excess with a hacked feeler blade. For any valve adjustments exceeding the middle (.012 ish?) of the range, you go hack up little disks out of a sacraficial feeler blade set available at any FLAPS.
ex: some valve somewhere in your engine is at .016", you grab a .004 feeler blade, cut a facsimilie circle of a shim, smooth the edges, and stick it under the current shim. No sliding contact between the shim and the valve, it just sits there trapped nicely and lasts a good long time. Is this guy for real?
Colin

 

Good luck with that, you'll never get them in place.

If you car badly needs valve adjustment, I would assume you have a rather high mileage motor? If thats the case might as well do it right and replace valve seals in the process.

 

The Lexus service manual for the first gen calls for inspection and adjustment of the valves every 60k miles.

 

I don't think its necessary to adjust them every 60k. Unless you hear obvious clatter, I wouldn't bother.

Its a difficult job because how cramped the engine is, and if your going to get in there it pays to adjust the valve clearance and replace valve seals, as well as valve cover gaskets. Of course it will require removing cams, so you might as well replace cam seals as well. Which in turn requires removal of timing belt, so might as well do that along with crank seal and water pump. Basically its a can of worms

 

sorry but the last thing i want in my valvetrain is bits of unmatched feeler blades.

 

All I'd like to do is get rid of or lessen the ticking noise... I don't think my heads have any real issues and my TB and WP were just done 16k miles ago. Can't I just have the valves shimmed and replace the dome cover gaskets and call it a day?

Jim

 

Sure you can.

 

Pulled off at a friend's house in Syracuse NY, decided the clack was on the left, stripped the left valve cover down:


Checked clearances lightly for general compliance, some were .014 ex, some were .012 in, not worrying about them, but of course the most inaccessible valve of all, the rearmost intake, was at a nice .017":


Apologized to this fine engineering as I had my friend push down on the tappet edge with a prybar while I used GumOut carb spray to break the oil film between the shim and the tappet, then magnet-pulled the disk out.


Cut a .007" feeler blade to the general width of the shim and dremelled the outside radius to match. Stuck it in the tappet with some oil, placed the shim onto it while my friend (under the threat of instant death) held the tappet down. Buttoned it up carefully since I had no gaskets:


I am so happy to have a quiet engine now. Currently in Plattsburgh NY, just hit 100,000 miles, averaging an easy 25 mpg, Rachmaninoff's 2nd Piano Concerto on the stereo, a lovely interstate car. Although complex, I find these cars have been easy to work on, even the stupid 12mm bolts behind the dipstick brackets. Will do the official ultra-accurate valve adjustment when the PROPER tools arrive in Atlanta GA.
Colin

 

Snap-On makes a tool that works nicely after you figure it out for the lifter buckets, while pulling the cams is easiest for those shims.

 

before i say anything, do you plan on replacing the piece of feeler blade with a proper toyota shim?

 

Of course. I am on the road as mentioned. When I get home, I will do the correct valve adjustment procedure with ground-down poker chips.
Colin

 

Well the plot has thickened.

I did a total valve adjustment of every one of the 32 valves in the engine, motivated by an alarming clacking sound that has been developing.

At the end of my valve adjustment procedure, every intake valve came in at
.006" - .008", and each exhaust valve was a good .011" with two at .010"

LEFT SIDE


RIGHT SIDE


EXAMPLE of HOMEMADE SHIMS


Now I am very happy with my valve train clearances. The engine runs splendidly, docile and quiet or like a scalded cat. Burns no oil. Idles smoothly. But the noise is perturbing, and I did the ticking Lexus search function here and read many accounts of others who have the ticking sound that I have.

Beyond a doubt this is not a "valve adjustment" issue. It is not a cam tensioner issue. It is not the fuel injectors cycling. Nor is it, as too many Lexus dealers and field reps have suggested, normal, by any stretch of the imagination.

Any LS400 people here dealing with this clack most noticeable at idle? Mine is cylinder #7 forward intake valve near the intake port area. I could almost swear that it is a:
collapsed hardened insert inside the tappet
out-of-round tappet
loose valve seat
gonzo valve guide
(latest diagnosis shows that the noise comes in and out of phase, while idling, about every 45 seconds to a minute it quiets down, then it comes back with a vengeance. Not oil pressure related. Not load sensitive. Has a harmonic at 2,800 rpm)

ColinInTheValleyofDarkness

 

Thought it best to get rid of all my feeler blade shims under the factory shims, and decided to do the timing belt here in Austin TX at 105,000 miles, a good time to take off the camshafts and have a look at the valve train to see what this annoying clacking was about:


These 1UZFE engines are a delight:


Found the problem too:


Lack of lubrication under the lifter had allowed the valve to slowly drill through the once-hardened pad in the middle of the bucket. Fortunately, this was discovered and rectified before the valve stem sustained too much damage . . . I think.

Though a long drawn out complex challenge, I enjoy working on these engines and I love the new silence . . .

 

Hello I have a 92 sc400 1uzfe engine that I am attempting to replace an out of spec shim that is noisy...the problem I am experiencing is that it is the no7 cylinder intake valve that is closest to the firewall...uuuuuhg...I have the special tool pliers and holder set but have found it next to impossible due to the tight confines and limited visibility(I am using a mirror) to compress the valve enough.One way the handle of the pliers hit the brake booster and the other way it hits the inside of the cylinder head.I am able to compress the spring somewhat and hold it down with the smaller end of the holder tool but that is not enough even to get a flexible aerosol straw connected to compressed air into the hole of the shim to break the shim loose...has anyone done this sucessfuly on the back cylinder??...any advice or tips would be greatly appreciated...I have basically concluded that I will have to remove the intake cam which leads to another question...after I position the cams at tdc is there any way of removing the timing belt off just the intake cam sprocket and keeping the belt tight with a ziptie to something (I am guessing by removing the tensioner from underneath to provide some slack) or is that just wishfull thinking...thanks for your time

 

What symptoms necessitate a valve adjustment?