You have a Yamaha built motor ,You cannot use any of the parts racer is suggesting here. The parts Racer is suggesting only work on the Mercury Built motors. You will need to find either a donor motor or the corresponding Yamaha Parts.
Those are the high performance version of that motor. A lot of people pulled the powerheads off of those and put them in the cars. Just because they were more powerful.
That is a false compression reading. Let it sit overnite and try it again and your idle could be lower. look to make sure the rollers are in good shape on the 50.
Retest your compression have never seen one of those that high. What is your idle speed? THat needs to be set in gear on a warm running motor. Not unusual to have a bit of a clunk when shifting.
It is a scott 3 cylinder lower unit, If it is the same impeller those are being made yet by people. Join the AOMCI and you will find somebody there to help you.
https://www.filterdiscounters.com.au/bf7609-baldwin-fuel-spin-on-replaces-wix-24104/
try here https://robertsmaritimesystems.com/Homelite_Outboard_Support.php
Or the AOMCI can help a lot with that. I believe those are Crosley car engines.
