The oil line question

[Truckedup]

 On the engine it appears the lower of the two oil ports is for the supply from the tank. Upper is the return ?  The lower port has an R stamped next to it, why? Thanks..
   The shop is just finishing up the engine machine work...The alloy head had issues.....Should have the engine parts next week  and start assembly...

[Seabee]

Not sure why (reservoir?), but you are correct.

[RichardL]

Both of mine are "F" on the bottom and "R" on top, which I take as "feed" and "return."

Richard L.

[berger]

there should be a F and R feed and return , if it is in bits it is a good time to put some petrol in the holes and see where it comes out you learn a lot about the drillings and how they work with the oil pump. if it is built up take your time and make sure you put the pipes on the right way. I got caught out when I was in a hurry and caused loads of damage and an empty wallet 

[Truckedup]

there should be a F and R feed and return , if it is in bits it is a good time to put some petrol in the holes and see where it comes out you learn a lot about the drillings and how they work with the oil pump. if it is built up take your time and make sure you put the pipes on the right way. I got caught out when I was in a hurry and caused loads of damage and an empty wallet 

I used compressed air in the holes....I see the oil feed to the motor goes past a ball and spring on it's way to the crank bush.. I assume the ball is a  wet sump check valve..?

[berger]

yes the dreaded wet sump ball bearing and spring, so you will know which holes correspond with F and R and if it is in bits a good time to take out the screw in the case and give all the holes a good seeing to with petrol or other and cotton buds, the grime they shift is best out than in. at the end of cleaning give the ball a tap with a soft drift to help it out on it's seat to prevent wet sumping