Have any of you ever experienced this problem?


About a year and half ago I rebuilt the engine of my 65 beetle (first time).  Within the past several months I noticed that my valves have been tightening up before I reach the 3000 interval mark for my next value adjust.


However, within the past month the problem has becoming progressively worse, to the point where I can no longer adjust out my valves for the 1,2, and 3 cylinders.  Basically I can no longer get my feeler gage in between the adjustment stud and the end of my valve stem.


Is it possible that my valve seats have moved?  These are rebuilt heads with only 10,000 miles on them.  What gives?  Any insight in this area would be much appreciated.





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It is possible that the valve stems can extend or stretch with heat. It is probably better to have the clearance a bit high and clatter than too tight and leak or burn. Here is a paragraph from Rob and Dave's web site  discussung it. Also the two sections from their site with more info;


Note: Keep track of which valves (if any) were tight, meaning had a gap smaller than .006", where the feeler gauge wouldn't fit through. You want to see if the same valves are tight next time you do a valve adjustment. If they are, you may have valves that are stretching and getting ready to break, so it would be good to remove the cylinder heads and have the valve gear inspected. You must remove the engine before removing the cylinder heads, but preventive maintenance is better than having a valve stretch and then break on you, which will mandate a complete engine rebuild. Typically, the #3 exhaust valve first exhibits these symptoms, so keep a special eye on that one.





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Yup, either the valves are stretching or you have a seat/s falling out, both are very bad.  If they let go while the engine is running, it will be a  catastrophic failure, not a wimpy little breakage.  --Ryan

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