Merc 165hp 1971 6cylinder, torque spec

[avenger21]

Hi Chaps. I have a 1971 165hp merc 6 cylinder. it is a GM 250 " motor. I am trying to find all the torque specs for,<br />Main cap bolts <br />Big end nuts (con rods)<br />Fly wheel<br />Cylinder head bolts<br />Rocker shaft.<br />Also any info on the re-fitting of the front damper/ setting the preload for valve lash/igniton set up.<br />The engine has only done 120hrs from new, but last ran in 1976. Any tips or info to help the re-build would be of interest.

 

[JB]

Re: Merc 165hp 1971 6cylinder, torque spec

Moving to I/O

 

[achris]

Re: Merc 165hp 1971 6cylinder, torque spec

avenger21,<br /><br />Main bearing cap - 65 ft.lbs<br />Big end nuts if the bolt size is 11/32"-24 ... 33 ft. lbs.<br />Big end nuts if the bolt size is 3/8"-24 ... 40 ft. lbs<br />Flywheel - 60 ft. lbs<br />Cylinder head - 93 ft. lbs<br />There is no rocker shaft. The rockers are on studs and the spec is 1 turn down from zero lash. <br />Front pulley bolt - 18 ft. lbs<br />Ignition timing - 6 degress BTDC @ idle (650rpm)<br />Point gap - 0.016" (dwell - 31-34 degrees)<br />Plug gap - 0.035"<br /><br />Have fun

 

[avenger21]

Re: Merc 165hp 1971 6cylinder, torque spec

Thanks for the info. The front pulley is only a press on item there is no retaining bolt, I have considered drilling and tapping a thread into the nose of the crankshaft so the pully can be drawn on by the new bolt?<br /><br />Having fun