Valve clearance after valve job (1 Viewer)

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So, I am re-assembling my new short block and re-worked cylinder head on my '96. I went to check the valve clearances and they are almost all way too tight after the valve job. I can't even get a .002" feeler through on some of them. I hope I didn't screw anything up. Anyway - any tips/tricks on how to "guess" at what shims to use, or is this just going to be pure trial and error?

Thanks.
 
I just did the HG on my 80 a few weeks ago. The shop I used re-cut the valve seats and then "tipped" the valves (cut off a small amount of material off the stems) to put them all back to the original spec. I kept the shims and buckets exactly the same as they were before. Everything is in spec. Perhaps you should have asked your shop about doing it that way. If the head is not back on, maybe it's not too late to have them to do that for you. Otherwise, you'll need to re-shim. I don't know much about shimming, but I would assume that the shims can be purchased in different thicknesses. Measure, determine what you need, shim, re-check, move on.
 
youl need either new shims or get the valves taken care of by the machine shop. you can figure out the correct clearance with a little math and the shim chart that is in the repair manual. th printing is too small to screen shot so your better off getting a hard copy or a pdf that you can print off.

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Yeah, I understand the concept - I was just wondering if there was any tricks for this situation for making an educated guess. As it stands, they are far too tight, and I don't know "how much too tight". Best I can do I guess is assume that the clearance is 0 and then measure the current shim thickness and go from there and order new shims after seeing if I can mix and match current shims to get the most in spec as I can.

I would rather just get new shims instead of tipping the valve stems. The machine shop did offer to set up my valve clearances for me, but I declined as I wanted to go through the process. Half of the fun of these projects is learning new stuff.

Thanks for the responses.
 
At this point you need to pull all shims!

Find the thinnest shim and install it in a position and measure, hopefully you will have one thin enough to do this. Do your calculations and order the appropriate shim. You must do this for all 24 positions. You must install a shim in all positions on each cam, you cannot turn the cam without a shim in place.

Or, order the thinnest shim and a few sizes above it and cross your fingers, each shim is $5.00

Another factor to consider is this, if you have to use the thinnest shim to achieve your clearance when new means you are going to have to pull the head and redo your valves as the engine wears. Valves move up into the head as they wear, meaning clearances are going to get tighter. When this occurs you will not be able to get thinner than the thinnest shim. You have no choice but to pull the head then or your valves, especially the exhaust, get too tight and then they get burnt.

This is going to be a big time consumer, it would be better to pull the head a get the shop to do the job they were supposed to do in the first place!! :bang:
 
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Well, I am not going to freak out just yet. I don't even know what shims I have in there right now. I pulled the buckets and reinstalled in the same order. Some still had clearance, just tight. If it turns out that I currently have the thinnest shim, or need the thinnest shim available to get it in spec, then I will take the head back down and have them tip the valves.
 

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