Toro V Service Manual page 71

4. Lubricate and assemble the needle bearings
to the crankshaft and install the crankshaft.
751.1.1207.26A-
6. Oil the parts and use the piston stop and
ring compressor to install the piston with the
"BTM" mark facing toward the exhaust ports.
NOTE: The letters "BTM" were omitted
on
some engines. However the small
"rectangle" should still be visible through the
ports.
Service Section 0-15