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General Category => Maintenance => Topic started by: TheRadBaron on February 06, 2011, 10:46:35 AM

Title: Initial valve shims after head rework
Post by: TheRadBaron on February 06, 2011, 10:46:35 AM
I just got the cams back in and timed.  I'm in the process of making measurements for valve shims.  I had the head off the motor and hand-lapped all the valves, hot-tanked the head and decarbonized all the valves and seats. 
I don't have a lot of experience in the matter, but it seems likely to me that the valve clearances will close up a bit after some miles due to the valves "taking a set" in the reworked seats.
While I'm shimming the valves, would it be a good idea to set the clearances at the loose end of the range  (.20mm ex, .16mm in.)?  I would still keep a close eye on them for the first few thousand miles.  I'd like to avoid having to buy more shims after the break-in period, but I will if I have to.  Or would it be a better idea for me to shim the valves into the middle of the range like I would normally?  Thanks.
Title: Re: Initial valve shims after head rework
Post by: RichBaker on February 06, 2011, 12:22:53 PM
It is always best to set the clearances to the high end.... these valves tighten up as they wear.  "A happy valve is a Tappy valve...."   :drinks: