Need help identifying "extra" port/vent on a rebuilt block for 1985 Johnson V4 120. J120TLCOS
The rebuilt power head that I was sent (have been told multiple time that it is compatible) has an extra port near the bottom of the block on the carb intake side that the original did not have. I will attach pictures that show the old crank case and the new/rebuilt case and I will point to what I am talking about.
If anyone could please help me identify what its for and how I should proceed. I have a lot of sentimental value in this rebuild and I really want to make this work despite me starting this rebuild journey with little to zero knowledge of working on engines.
Now the port on the old crank case has a matching vent/port for recirculating back to the top of the crank case. My theory is that the "extra" port/vent is needing to be Y'ed in before the check valve like the lower one.
Hopefully some of you can make sense of what I can not.
Thanks.
The rebuilt power head that I was sent (have been told multiple time that it is compatible) has an extra port near the bottom of the block on the carb intake side that the original did not have. I will attach pictures that show the old crank case and the new/rebuilt case and I will point to what I am talking about.
If anyone could please help me identify what its for and how I should proceed. I have a lot of sentimental value in this rebuild and I really want to make this work despite me starting this rebuild journey with little to zero knowledge of working on engines.
Now the port on the old crank case has a matching vent/port for recirculating back to the top of the crank case. My theory is that the "extra" port/vent is needing to be Y'ed in before the check valve like the lower one.
Hopefully some of you can make sense of what I can not.
Thanks.