How to adjust Blacktop 4age tappets?

[overkill]

just wondering how one goes about setting valve clearances on a 20v 4age with the shim setup it has?

[Zak]

You swap the shims to the required size.

It's a bit of d**king around, but it's not very hard.

[bluemaumau]

16V Valve clearence (cold)

Intake 0.15 - 0.25mm / .006 - .010 inch
Exhaust 0.20 - 0.30mm / .008 - .012 inch

if you dont know how to do it search "4age valve clearance" in google.

[matt dunn]

Try this for a 20V,

Intake 0.19- 0.29mm / .007 - .011 inch
Exhaust 0.39 - 0.49mm / .015 - .020 inch

[bluemaumau]

whoops, i assume 16v for everything

[overkill]

thanks guys, i've just not done clearances on anything with this shim setup before.

i'm guessing it's put the cams back in, measure clearances with feeler-gauge and use vernier calipers to assess height differences in the shims i have?

(since i'm not going to be buying new shims.. i have 2 silvertop heads in addition to the BT one i'm doing.. i figured i must be able to find something to get each valve to the where i need to be)

does this sound at all like a good idea? i'm going on the assumption that there aren't any shim/bucket differences between the BT and ST since the valves carry the same part no.?

correct me if i'm wrong

[sergei]

You will need to use micrometer, vernier is not accurate enough.

[overkill]

thanks

[matt dunn]

You will need to use micrometer, vernier is not accurate enough.

If you meaure them like the way tou would with a vernier you will stuff it up like my head was the first time it was done.
Now I do it myself.

You need a micrometer? and something that will fit inside the shim to measure it.

Think of it like this
The shim is shaped like a bucket and you need to measure the thickness of the bottom of the bucket, not the height of the top lip of the bucket from the base.

PM me if you dont have the righ shims as I have a small selection here too.

Matt

[Logan]

or you get a machine shop to do it by recutting the valve seats, then tip grinding the valves to suit.

[matt dunn]

or you get a machine shop to do it by recutting the valve seats, then tip grinding the valves to suit.

Another good way to stuff your engine.

The shims then come down the shaft a bit more as there is less distance between the end of the valve stem and the valve keepers.

That means that the shim can push on the valve keepers not the end of the stem, and when it pushes onto the keepers, it drops the valve into the cylinder, whcih pretty much destroy's everything. Wanna see pictures? lol

Not my engine but another local one I was asked to look at.

[Logan]

Good point matt. I wonder how how much you could away with before it starts becoming an issue. I guess as long as the overall valve length was within spec it could be ok?

[sergei]

There is another way - very time consuming - trial and error - this way you dont need micrometer. Just feeler gauge will do and pen and a peice of paper.
Measure original settings, find the ones which are off write them down how much they are off (and position they are in). Get a random spare shim, replace and measure, if it is off mark the shim how much it is different to original one. Continue untill you get right clearance and whole pile of shims with known relative difference. That is how I done it when fitted black top cams in mine (the only difference I had to swap arround a few shims to get right - actually come to think of it I did not use any spares, just the ones I had, although there were only 4 off, if I remember correctly).

[overkill]

sergei, that was my original plan. but my uncle has a micrometer and i think they're only like 60odd dollars anyway.

thanks for posting that as an option

TS is a cool place ;D

(goes for everyone who replied here actually)

[matt dunn]

Do you have a list of the shim sizes available and there numbers?

I have found a few that have the shim numbers on the side to tell what size they are.
Interestingly enough all the marked ones were 28's.

Matt