no compression 331
 

Hi, maybe someone can help with some ideas of what to check,................. i have just done a valve job on my 53, 331. before i started i had no compression on no. 8. other cylinders all reasonable, i found no. 8 had two bent pushrods and both valves no good ,i put very light oil onto no. 8 piston, it took two days to soak away, so i thought rings must be good, bores were perfect, ok everything refurbished and correctly torqued down, re test,. no compression on no. 8 ..........why? ...i am completely mistified what could be wrong? any ideas other than a compleat tear down. thanks.

check to make sure that the piston ring ends are staggard and not in line

Remove valve cover and crank engine, check operation of rocker arms and valves, make sure valves are openning and closing correctly. Were valve springs replaced when valve job was done? Was valve installed height checked, it is possible for the installed height of valve to be too high and and valve won't seat - causing low/no compression. A "Leak Down" test would be helpful in determining problem.