Valve shim clearances.

[ae86 slide]

Ive replaced my valve stem seals in my 4agze and at the same time I am checking the clearances for the valve shims to cams.
Most of the clearances are within spec (intake 0.006"-0.010", exhaust 0.008"-0.012"), most are just within the clearances (on the wider side) and some are just over eg. 0.011 for intake and 0.013 for exhaust.
Also one on the exhaust side is 0.016 and the other shim on the same cylinder is 0.012.

My first question is that if one is 0.016 and the other on the same cylinder is within spec at 0.012, does that indicate a problem? like a bent valve etc.

Second question is, for the clearances that are only just out (by 0.001") can I just run them like that or is it best to hunt for a shim that is a tiny bit thicker.

Any input is a appreciated, thanks lads.

Jase

[ae86 slide]

Any one out there checked there valve clearances before?
after talking to a few mates who have never even bothered to check this Im thinking Im just going to drive it the way it is.

[ke70dave]

ive never personally checked my 4age valve clearances (done it on a few other pushrod engines), but when i got my 4age head skimmed and pressure tested they replaced a few valves and checked all the clearances for me. apparnetly they changed a few shims....

i think it would be worth giving an engine builder a call and seeing what they think.

[blair]

I checked mine when i did valve stem seals aswell man, a few were WAY off, but that was aparently because the previous owner got them all mixed up by accident.

I just got them all within tolerances by swapping buckets and shims around (after like 4 pages of maths haha)

All i now is that if they are all out of wack, the motor makes realy annoying noises (rattles and shit). Fucks me if its actually damaging or anything?

[ke70dave]

hmm not good...

having to much clearance is better than having to less. apparnetly if there isnt enough clearance you can burn the valves out, as they might not be properly closed all the time.

but if you have to much clearance id say you will get excess wear on your cams and shim/valve pusher thing...whatever the cam contacts with (bucket?). that would be the rattles that you are hearing.

i believe you can buy the shims in any size you want, through either toyota or i heard a motorbike shop can supply them as well. but ive never done it though so cant confirm.

[Skylar]

Shims are like 22 bucks each, then dude at counter goes I'll give you trade price but it's still 18 bucks a pop. and on top of that "only limited sizes available". Yeah, I just pulled another head apart that I wanted to keep together and got it with those shims.

Cam contacts the shim on a 4age. The shim sits in the bucket/lifter.

To the OP, different clearances on same cylinder means nothing. Just swap shims/buckets around 'til they're all in spec. 0.001" over is fine. It won't kill anything. I did shims on my engine and thought it was all sweet until I checked them a few months later. One of the exhaust side clearances were 0.38mm. Coupla the inlet ones were over by .05mm. Just swapped them around with shims out of the other head. I aim for middle of ground (.20mm and .25mm, I think) but if they're within spec, I leave them.

Check shims if they're loud/engine running shitty but don't worry about them if they seem fine.

Also, if head was media blasted, make sure you GET THAT SHIT OUT!!! Head looks cool and all but it kills heads AND cams. It's probably in the bottom end too by now. Shoulda picked up on it when I noticed the cam caps screws were bottoming out against the sand and had to clean them out with a tap.

[Jip86]

well Toyota only sell shims in 0.002" increments so mine is 0.008" to 0.009" intake and 0.009" to 0.010" exhaust as thats as close as i could get them