.462'' for finding t. d. c.?

[Magcat 62]

i cant understand the .462' method for findind TDC? WHY not just find TDC and set pointer at 0 ? dumbfounded!

[ChrisCarsonMarine]

At true tdc the crank journal is pointing straight at the cylinder,and can rock a few degrees either way before the piston actually moves.I don't know why Merc decided .462 was the measurement to use,(they chose .464 for inline motors),but it's not a special number...just an arbitrary reference point to determine true tdc by knowing the motors geometry,Chris

[TEXAS20225]

tdc is tdc the 462 is the method to make sure timing pointer is set at 462 correctly after you do the 462 with the dial indicator

[Magcat 62]

At true tdc the crank journal is pointing straight at the cylinder,and can rock a few degrees either way before the piston actually moves.I don't know why Merc decided .462 was the measurement to use,(they chose .464 for inline motors),but it's not a special number...just an arbitrary reference point to determine true tdc by knowing the motors geometry,Chris

I was thinking that was the theory i use the old piston stop method fly wheel c-clockwise then clockwise split diff with dividers on flywheel see what pointer says. old school but pretty close; i think! Thanks

[ChrisCarsonMarine]

I was thinking that was the theory i use the old piston stop method fly wheel c-clockwise then clockwise split diff with dividers on flywheel see what pointer says. old school but pretty close; i think! Thanks

That will work fine,and actually the method i use on motors where the spark plugs are installed at an angle and a piston depth dial indicator won't work...Chris

[Magcat 62]

im gonna pat myself on the back. im a senior citizen 65 what worked 40 yr ago still works today! like a chopper prop LOL THAKS ARTKS ART. Wish i could send you my mint 1987 220 efi and get it right money is not an issue 1 week it turnns 6000 next week boggs turns 5000 let it sit turns awhile 6000 again. never in salt water good comp all 6. mark on plastic cam not touching roller at idle. has slack in linkage? dont know