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George
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Hi guys.  I got a rebuilt head that looks to be in good shape from someone who didn't know much about it.  Now, I am not sure about how to set the valve clearances.  I thought maybe I could measure the clearances without a shim in and then do the math to figure the size shim I needed.  However, it occurred to me that this would not take into account the amount the shims sit down into the spring retainers.  Is this a standard depth?  Or is there some other way I should be doing this?  Or do I need to get a machine shop involved?

 

Thanks

george

Jensen Healey
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Do you have any shims at all? Maybe one of the east coast guys has a box of shims you could use to get close before you start buying the exact shims you need.

George
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Thanks for the idea.  I do have some shims and I thought maybe I could use them to get a measurement as a basis for the size shim I needed, but they all seem to be too thick (no clearance at all with them in place)

Dakota123
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In some cases the pad on the underside of the bucket may contact the valve stem, allowing you to take the measurement with no shims.  You can tell by putting a thin smear of grease on the valve stem tip and see if it gets transferred to the bucket when you place it on top.  If it doesn't then you can take up the gap by using washers or scrap hard plastic or something (as long as it's rigid and flat).  There's a good chance that first measurements are only going to get you in the ballpark (+/- a few thousandths) anyway so this method isn't as hokey as it sounds.

LambandAndy
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George,

I have a set of shims that I had ground to the minimum thickness to use at as a starting point.  Send me your address to limey01@aol.com and I can mail them to you.

Andy

George
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Thanks, Andy !  Will do. 

I had another thought, would it work to put a sraight edge across the top of the retainer and measure the gap to the top of the valve, then add this measurement to the size of the shim needed?  I am getting a little out of my depth here . . .  Anyway, the thin shims you have should do the trick

thanks again

g

Dakota123
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The pad on the underside of the bucket will sit down below the top of the retainer, so that won't work.  Here's an image of the underside of the follower:

http://qedmotorsport.co.uk/qed-shop/view-all-products-in-shop?keyword1=cam%20follower%20bucket


George
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I knew those pads were there, but I hadn't fully considered their implications!  Thanks for the advice.  I'll wait for Andy's thin shims.

 

g



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