Valve clearance not changing with adjuster??

Just thought I'd pop the rocker cover off the CF (1.8 slant) and take a look at the valve clearances before I set the timing and fuel mixture. Not got as far as the inlet valves yet, but all the exhaust valves are very tight. after about an hour of swearing and general faffing (so engine may have cooled a bit), my best guess is I get a clearance of about 0.007-0.009inch, which is way below the min of 0.015inch. What has me stumped is that even when I tried withdrawing one of the adjusters WAY out of the tappet, the clearence didn't seem to open up. Could it be that the tappet is stuck some how and needs a tap on the top to move down a bit? I know that undersize adjusters are avalible, but am just confused by the way turning the screw seemed to have bugger alll effect.

Also, am I correct in thinking that each adjustmewnt must be a complete turn, and if so how do you know when a complete turn has been completed? I couldn't feel any feedback on the screw.

Engine stars and runs fine, considering it hasn't been used for 7 years, and I have yet to check timing etc.

thanks - a rather confused Phil

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