Valve Clearance adjustment

[gorillaguy8]

I was wondering if any one knows how to adjust valve clearance. Im completely rebuilding my car and im almost ready to drop the engine back in. Any pointers will be helpfull, thanks.

[rnoswal]

Well here is a try at it. First you have to measure all the clearances between the cam and the shim holder(bucket). The gaps for intake and exhaust are different. Mark all of these down in order and on a large enough sheet of paper to put these other measurements on it. These measrurements are made with the cams on and tightened down. The head can be on the car or off.

After measuring the gaps and recording them, note the ones that are too close or too wide. The ones with the corrct measurements will of couse be left alone.

Next, take off the camshafts, unless you have the nice tool that allows you to remove the shim with the cam still on the heads. Either way, you have to measure the thickness of the shim. If you clearance on an intake valve is 2 thousandths too wide, then you need to find a shim that is 2 thou, thicker and just the opposite if the clearance is too small.

So you need a micrometer to measure the thickness of the shim, not a vernier caliper, but a real micrometer. You really should have access to a good assortment of shims at this point too. I have collected several from the engine in junkyards and from my own stuff.

After you measure a shim, mark the number down on the shim with a magic marker, that way you will have it for future use on another valve. It is a tedious process but after you do a few, the job get easier. Take your time with this and make sure of your measurements.

It would be best to retake the measurements after relacing the shims and putting the cams back on. A valve that has an initial gap of + or - a thousandths is ok, especially on the wide side. Too close and it can cause the engine to run a bit hotter, too lose and you can hear the light clicking through the valve covers.

Make sure the shims and the buckets are clean when you replace one so you get an accurate measurement. After you do this make sure your cam gears are adjusted properly, but that is another story>

Good luck and let us know how it goes.

Russ

[gorillaguy8]

Cool, now would anyone know where i could get ovesized shims for the ones that are way to big? thanks

[mrnickleye]

Toyota. and perhaps a good machine shop.

[gorillaguy8]

I was actually able to find them on Horsepowerfreaks.com, they had a wide variety of over and undersized shims.

[donkey]

I just brought my 1990 NA into a nearby well recommended shop for a leaky valve cover gasket replacement and valve clearance adjustment. I didn't have the shims to do the job myself, nor the experience. After measuring the clearance, the mechanic found 3 intake valves out of adjustment (two on one cylinder). All were too tight, and the worst was 1/2 the minimum spec. So, without replacing any shims he puts everything back together and tells me (when I come to pick up the car) that every time he sees an intake valve that needs adjustment on these engines it turns out to be carbon deposits built up under the valve and it doesn't do any good to go through the whole Toyota procedure for replacing the shims, the only way to solve it is to remove the head. He recommends using Redline Fuel Injector cleaner to try to solve that problem as a cheap solution. Is he right? Is the whole Toyota recommended shim measurement and replacement procedure to adjust intake valve clearances just a crock of shit when it comes to these engines (7M-GE)? Is it really not going to solve the problem of having tight clearances on those 3 valves? Would you not worry about this like he didn't? I've been running my car on E85 (with modified injector pulses) for the last 6000 miles, so I find it hard to believe I would have carbon depsosits under my valves causing this maladjustment. The head has 136000 miles on it, and the short block about 36000. Any knowledge or opinions would be appreciated.