Pull the crank pulley around to TDC.

pulleys have no Top Dead Center (just in case, dennie, you don't have a clew
what TDC stands for, a likely case). Pulleys are round. Therefore a pulley
can not have a TDC.

pulleys mounted to the front of the crankshaft on engines where a belt power
takeoff is installed *usually* (but not always) have a mark to show ****when
cylinder # ------ 1 -------- is at Top Dead Center****. This mark can be
used to show when #1 piston is at the top of its stroke but can NOT be used to
determine whether the piston (in a 4-cycle engine) is at the top of the
compression stroke (when you need spark) or at the top of its exhaust
stroke/the beginning of its intake stroke.

A mechanic who installs the distributor in the 50-50 hopes of having it timed
right, tries the engine to see if it backfires, if it does, takes out the
distributor and resets it 180* around is no mechanic at all. He is a fraud who
should be sent to jail for stealing money from customers.

by the frickin way dennie, "ASE Certified Master Auto Technician and Marine
Engineer in training", next time you are "installing" (I use the word loosely)
a distributor and find somehow once again yet another time you installed the
thing backwards, instead of removing the distributor and then turning over the
engine a full turn and reinstalling the distributor, just move the ignition
wires around the dist cap 180*. That would take maybe ten seconds for even a
"Marine Engineer in training" like you.

geesh, somebody hired this guy to fix what?