Hi,
John R, or maybe Dr Dick, posted a seminal article on this forum about the oil transfer valve. I'm not too sure of the details, but here's my understanding. The engine can wet-sump a little, and the excess oil will be blown into the primary case, which has lots of volume to absorb it. Once running, the engine will slowly suck back excess oil from the primary into the engine. The 1952-1954 was a primitive system, with major improvements in 1955 (or very late 54's with the removable transmissions).
The 1954 Spare Parts Catalog (SPC) shows the often-lost, and very hard-to-find parts shown below. There were not in the 1953 SPC, so they must have been introduced mid-1953, and used through late 1954. In 1955 they went to a different system. See the SPCs over in the Literature section.
- 1954 Spare Parts Catalog
- 25100.jpg (79.63 KiB) Viewed 17559 times
I believe this tube was used to suck oil OUT of the primary and back into the engine. There seems to be some disagreement about what o'clock the tube should be facing. I'm finishing up my chassis before assembling my engine, so I do have one, but not sure which way it goes. But I believe it should be pointing towards the bottom of the crankcase. If you don't have this tube, and perhaps more importantly, the check valve, you may be blowing all the oil out of the crankcase into the primary, with no way to suck it back - and your primary filling up.
The early oil pumps has a check valve and a relief valve. These both used a half-ball bearing attached to a "stalk", with a spring. 1955 and later models went to a plain ball bearing and a spring, and then the relief valve got eliminated. For your 1954, you need to find a good welder dude who can weld a thin rod onto a ball bearing, so you can use this with valve grinding compound to lap the check/relief valves in. The Sportster Service Manuals tell you to whack the ball bearings into the seat with a drift - a little more brutal method. But for the 1954, you need a good welder dude.
If your cover is badly worn, you might try one of Tom's modified covers. But first, I'd work on your check/relief valves.
Dave
Why, oh why, did I pick a 1954 KH to restore...