I've never understood the claims of needing to adjust them constantly. I usually tune my old 223 and Y blocks every 10K miles and thats just plugs, points and timing. If the valve noise hasn't shown any change I don't touch them until it does. I think my 223 went 30K the last time before needing a slight adjustment..

Possibly back in the old days when we had crappy oil parts wore faster, I remember Y blocks from the 50's that were lucky to make 60K before needing a complete overhaul. I'm sure a lot of those were do to lack of maintenance by the owners.

 

Well wanted to try it again, just to see how it was holding up. Taking the plugs out to check on those too, btw sure makes turning over the motor easier. I try not to abuse the starter so do it by hand.

90 deg marks on the damper are handy. The book method minimizes the number of crank iterations by jumping around to different intake and exhaust valves, turn crank 180 deg, 270 deg, etc. Tried a few different methods just to see how they end up. Jumping around to different cylinders definitely saves time, try not to forget any though. Adjusting both valves on a cylinder at TDC following the firing order seems foolproof, though takes a little longer.

Yet another way is to adjust any cylinder's intake valve when that exhaust valve starts to open, and adjust the exhaust valve when its intake valve is almost closed.

Tried to cinch them up a little tighter than they were, but on startup seemed to run rough. Reset idle and mixture, rso-so idle and took it for a spin and got it warmed up. It did have a little more punch at higher speeds but with the stock size carb and motor, cam, etc. it doesn't matter a whit anyway. But, low end driveability and off idle acceleration seemed to suffer and it kept stalling at lights and stop signs. So with it warmed up good, I set them all back to 1/4 turn loose from zero lash and got back the nice smooth one potato two potato and no clatter. It seems to me using a flat feeler gauge at .019" would typically leave them WAY too loose, the 1/4 turn from zero lash method works really well and is consistent.

 

Here is how Tim Mc Master does it. He has done it a time or two.
Second method

 

Yeah, I've watched those. Problem is, many people are going to have trouble using a feeler gauge on Y block heads. He has done it a time or two and makes it look easy. And it is, but maybe not for folks who don't build racing motors or familiar with this kind of thing.

There's plenty of conflicting information out there too - "they must be adjusted while the engine is running". Maybe the book sez so, but... If the rocker faces are worn, an inexperienced sort setting lash with a flat feeler gauge to .019" will probably mean dropping push rods, I'd wager. They will be way too loose. The 1/4 turn method is tough to beat, both accurate and easy.