[Cees van Rhijn]

Hello John
Thanks for your answer. Yes, I have also found such seals in the lower oil channel of the rocker box. These are held in place by a spring that is locked by the center screw with the drain hole. The felt had completely deteriorated. I will put new ones in it.
Hopefully the leakage will now decrease.
Kind regards, Cees van Rhijn (Netherlands)

[singleminded]

Both ball valves are necessary to give good oil pressure, without the top one the telltale will not operate fully.
The reason for your over oiling at the rocker box may be the same as my 9A when i first got it on the road, I had oil dripping off the bottom of the engine it was so bad.
At the rear of the bottom gallery in the rockerbox, the one with the plug with the screwdriver slot, should be one or two felt seals to control the amount of oil getting to the valve guides. Because the screw at the front of this gallery has a hole in the middle a pool of oil builds up in the gallery and the felt seals just allow a gentle weep of oil to the guides, or at least should, they do on mine.
I made two felt seals about 5mm thick to do the job, Try just one to start with which is what I did.
Good luck  ..John hood

[Cees van Rhijn]

Hello Sunbeam colleagues
Concerns oil system of my Model 9 (1936).
Can anyone inform me what is the purpose of the overflow valve at the rocker box.
Please see attached diagram.
I am currently trying to control the oil leakage from the rocker box at the rocker arm bearing. I have renewed the bearings with minimal clearance. Reduction of the orifice is not possible because this would also compromise the oil supply to the camshaft distribution. I am now doing a test by feeding a small oil flow for the orifice to the pushrod area via a newly turned oil supply fitting and a newly drilled oil channel. During a test with an oil syringe, this appears to work well. I reduced the orifice to 0.5mm. Whether it works in practice we will find out.