Thread: HELP! Damn valve shims...

Okay, I got the valve shim tool from Calum yesterday, and started taking measurements...

So what I'm gathering, is that you take the valve shims out, and leave the rocker arm guides in place.

Next, you "zero" the dial indicator (I assume you adjust the nut on the bottom of the dial indicator until the dial sits at zero, with the tip of the dial indicator flush with the valve stem. Once you acheive zero, you then move to the rocker arm guide and take the measurement. This measurement is the # that you're going to need to order the shims with, right?

If this is correct, and I've done this measurement like 10 times already, this is what I get...

Intake Cyl 1:
.117 (2.975mm)
Exh. Cyl 1:
.122 (3.100mm)

Intake Cyl 2:
.121 (3.075mm)
Exh. Cyl 2:
.121 (3.075mm)

Intake Cyl 3:
.122 (3.100mm)
Exh. Cyl 3:
.121 (3.075mm)

Intake Cyl 4:
.120 (3.050mm)
Exh Cyl 4:
.116 (2.950mm)

Now here in lies the problem...

I took all shims out, and didn't leave them mated to a particular valve pair, because they were all out of whack, apparently.

Valve shims:

3 EA @ .118
2 EA @ .119
1 EA @ .116
2 EA @ .117

Is it quite possible that the previous owner (apparently the motor was rebuilt, due to paper headgasket), just slapped some shims in? Or is it likely that my measurements are wrong between the valve stem and the rocker arm guide?

What's the tolerance range? plus or minus .001? It appears that I'd only be able to re-use 2 shims.

Could the new valves that were installed be that much different? Or is it likely that the springs and retainers altered these dimensions and I've been driving around like that for a while?

There are no distinguishing marks on the shims whatsoever. (The FSM states that there will be numbers on the shim.)

Any help is appreciated. I'd love to get it back together as soon as possible. (Dealer states that it's 3 business days to get these shims in, which SUCKS.) I wonder if Greg V. can work some magic?

Thanks in advance guys.

ass lol

Have you looked through this?:

http://www.sr20forum.com/technical-information-library/145625-how-measure-valve-shim-heights-pics.html

Yeah I read it and read it and read it again.

I re-did measurements, and now they're all different. I was able to re-use all shims except for two.

I verified by measuring paired valves with the shims in place, and only have .001 of deviation between shims. Some are borderline .002, but it's hard to tell because every time I measure, they fall closer to .001.

Now I need a .113 and a .114 or .115

I was told by a mechanic here at the office this morning, to use an emory cloth to bring the other shims down to the needed sizes. Think this is an accepted method? I know emory cloth won't really scuff like sand paper/grinder wheel would...

i dont think it would hurt it. i used the same stuff to pollish my crank up when i did my main and rob bearing

That's what Tim did.

Went to town on the shims last night, and got them filed down to within tolerance. (+/- .001").

Used a coarse emory paper, then a fine emory paper, and polished them out with 2000 grit sandpaper. They came out great, but I didn't stay on one side of the shims. I did about the same amount of work on either side, and since they're mirror polished, I'm not worried about them getting damaged or damagine the rocker.

Anyhow, head is fully assembled, had to pull the pans again because I screwed up with the timing, and wanted to be extra sure that I had it right.