I need some info on the procedure to rebuild my lower unit. My serial # is A729226 (made in Canada 1987 Mercury 70HP 3cyl outboard). The serial # corresponds to B110045 in the US. One mechanic I talked to said this was the "Bigfoot" model. It is quite heavy duty compared to the regular LU's of the same year.<br /><br />What I want to know has to do with the clearances for the pinion gear bolted to the base of the drive shaft, and the forward gear, and specifically how to go about checking the clearances so the gears dont blow up.<br /><br />My manual doesnt really cover this model, it is a Clymers manual and I am dissapointed. The procedure in the manual for a slightly different 1987 LU uses metal shims to set the clearance. The parts diagram in the manual shows the positioning of these shims. Now I have also checked a parts diagram for my specific model at mercruiserparts.com and there is no indication of shims present. So do I just bolt it all in place or what would the correct procedure be.<br /><br />Thanks in advance.
