Once you have removed the side valve cover you are ready to adjust the tappets. You will need a .016 feeler gauge (an angled tip works best) Have someone turn the engine over by hand with a socket on the flywheel nut. This is a 1 3/8″ nut. If you don’t have one,you’ll be stuck with using the starter motor. Manually is much easier. Next,visually determine when the lifter is is the down position. The spring will be uncompressed at this time. Place the feeler gauge at the top of the tapet and check clearance. There should just be a slight drag on the gauge. If you can’t get the gauge inserted, it means that the valves are too tight from wear-in and need to be adjusted. Ditto for too loose. You will need 2 open end wrenches for the tappet and lack nut. I believe they are 1/2″ , but I don’t remember positively. Loosen the locknut,insert the gauge and turn tappet until proper slip fit is achieved. Tighten down locking nut. Repeat with all 8 (or 12) valves in the down position.
Reassemble the cover and manifold with new gaskets. Clean surfaces perfectly before applying gasket sealer and new gaskets. I use Permatex spray copper which fills small voids. Coat all surfaces. Be sure and clean manifold studs and REMEMBER to seal the manifold end bolts with teflon or other thread seal as they go right into the water jacket.
Snug all bolts evenly. Personally, I don’t use a torque wrench here. Its not possible to get one on the lower studs and I just rely on my own feel .The gasket will compress a bit and give it all the holding power it needs. Just go easy, CAST iron breaks with too much torque. Reinstall the carburetor and any hoses and lines which you removed to disassemble.
Then…Start your engine and if you did this properly, it will be smooth running with proper compression. If your engine is not at least 90 PSI across the board,it’s time to pull the head and check pistons and cylinders.
