Chrysler 75 and 85 HP Outboards Service Manual OB 3646, Page 90Get this manual
AThread barrel of timing tool (Special Tool NoTA 2937-1) about 3 of the way into spark plug hole in top cylinderBInsert rod part of timing tool (Special Tool NoT 2937-1) in barrelith two marks 2555 to the outside Figure 45 The distance between these marks represents 32 or .278 (6 .95 mm) 5Find Top Dead Center as follows: AHold rod tightly against piston and rotate crankshaft clockwise two full turns and stop at top dead center (TDC) This is where timing tool rod complete ly stops moving BScrew barrel of the timing tool in or out until inside line of the timing rod lines up with edge of barrelFigure 46 CAUTION
When outer line of rod is on edge of barre l, piston is at 32 Before Top Dead Center (BTDC) Figure 47
If dial indicator is used, 32 is equal to .278 (6 .95 mm)
SPECIAL NOTE
85 .Pperformance engine must be timed with dial indicator tool due to shorter crankshaft throw32 BTDC on this engine is .266 As rod time to barrel engine is coming out of barrelcheck from time to see where outer line is in relation to end of If outer line goes beyond edge of barrelmust be rotated clockwise again