I am seeking information from those of you who have had a lot of 770's apart.

I have had 3 770's apart. Two of the engines have a small pin, about 2.4mm in each bearing. These pins rest in small notches that are cast into the intake side of the upper case half. When the bottom half of the case is installed, the pins are captured in those notches.

I purchased a 3rd engine (non running condition) in my quest to collect parts to reassemble an engine which someone assembled with incorrect parts.

This 3rd engine has larger, 4.9mm pins. The pins in this engine fit into holes in at the very top of the bearing location in the upper case half. (They would be on the bottom while the case is upside down during crank installation) Then when the crank is lowered into the case, these 4 pins must fit into corresponding holes in each bearing. I believe the engine I purchased failed because 2 of these pins, on the PTO end of the crank, were not in the bearings correctly. This held the cases apart, causing an air leak which melted the PTO piston. It also was not good for the case as it appears one of the bearings was able to spin in the case.

The 1999 service manual states, "Be sure the alignment pin on each bearing is positioned in its respective alignment notch in the crankcase." The photo shows notches between the case halves as described above.

My questions are;

Have any of you with more experience see both types of bearing alignment pins on the 770's?

When you purchase new bearings, do those alignment pins some with them or do I have to make new pins?

Have any of you ever had these pins work their way out and damage your engine?

Thanks,

John