Crankshaft rear bearing oil tube

Hello Allen, PM sent.

Good afternoon Ivor. Your down under! Can I give you a phone call tomorrow arvo if that is suitable? Just need to get the right solution
Regards
Allen Cox.

Hello Allen,
The square cork segments are seals as you suggested, I apply some non hardening liquid aviation compound to these. The composite cork sump gasket seals the remaining face. The half moon plate is held in place with "hammer drive screws" I replaced these with hex head cap screws and used liquid aviation sealer under the plate. With regard to rear main seal leakage, Lycoming designed the oil groove and oil wedge to ensure enough there was oil to lubricate the rear main bearing without excessive oil flow to to slinger cavity. If the rear main bearing has the oil wedge and or oil groove machined incorrectly this will allow a higher oil flow to the slinger cavity which may cause excessive oil to weep from the rear main bearing. I believe some Auburn owners have fitted various seals to make the rear main bearing oil tight. A few of us in Australia have fitted A Labyrinth seal, I can send some photos and comments if you are interested. If the rear main bearing is re-babbited and machined as per factory it should not leak unduly. It would be interesting to see if other members have fitted additional sealing.
Ivor.

Thank you Gentlemen for your assistance. I did not have a motor together to get all these fine details.
Can I please ask another question about the rear main seal.
I am guessing that the square cork blocks on the side of the rear main bearing cap stop oil getting out!
The sump seals over the rear main cap and keeps the oil in.
There will be a small amount of oil coming out the rear of the main bearing and the slinger/fixed washer on the crank will throw this out into the cavity to drain into the bearing cap and drain out the bottom and through the tube I just asked about.
I believe the bottom of the tube is down below the top of the oil in the sump which stops blow back up the tube?
Is there any seal/felt that is under the half moon plate that is screwed on the back of the block that provides a dust cover between the crank and the block?
Or is there just a small gap that get a bit of oil and dust and closes up ant gap that may be there?
Thank you all.
Regards, Allen
This is just in front of the flange where the flywheel attaches?

Hello Allen, Dimensions as per Mike, the thread length is 7/16" and is 1/8' NPT

IThe pipe is known as 1/8 pipe

I don't post pictures but the tube is 5 1/4" long, .410" in OD, and .275" ID. Hope this helps .
CORDially Mike

Does anyone have a good picture of the oil tube fitting for the rear main bearing?