Inter oil pressure

Disconnect your oil feed and check flow..... dont rely on the guage. (Pump some oil in the centre fed with your oil can to be sure you are lubed).

Have you got the right "orificed" centre feed valve in there? not the one from the crank!

Have you got your camshaft asembled correctly????scrolled bush etc.

Cant think of much else right now...

J

Previously paul_nicholls wrote:

Hi Guys

I have just finished the rebuild of my 1950 Inter. It has centre oil feed to the cam box. I put in a new pump and now new pressure release spring.

The problem I am having is getting a good oil pressure to the cambox. I have set up a 0-15psi gauge in the oil feed to the cambox. I only get 1 or 2 pound when cold. I have tried adjusting the pressure release and it makes no difference. I did try putting in 2 balls to prevent the release operating and the pressure goes off the scale. The tell tale operates perfectly and with the new pump comes up when kicking it over.

It seems that the pressure is overloading the release ball and spring.

My question is has anyone had this problem before?

Maybe pack the spring to get more pressure?

Very annoyingly, before the rebuild with a knackered big end, piston and oil pump, I was getting somewhere near the right pressure.

Paul

Got to run it in for the ManxGP

Paul; I think you got the oil feed valves mixed up (Crank/Cam). Your high pressure is caused be the small restrictor to the crank.

Cheers

Jon

Previously paul_nicholls wrote:

Well I have spent days looking at this now. All the jets are in the correct position. I got a friend round with an expensive endoscope to look at the pressure relief channel. The end where the ball sits looks like it has had too much "seating of the ball with a brass punch" in its life. The seat looks almost hemispherical.

Should the adjuster be able to reach the ball. Does the spring control the oil pressure. It does not seem strong enough to do so.

Or does therestriction of the oilway by the ball control the pressure. It seems to me to be the latter and the spring is used as a check valve to "stop" wet sumping when the engine is stopped.

Working on the latter assumption, I made a longer adjuster that reached the ball (due to the recessed seat) put in a 1/4" ball instead of 7/32" to get a better edge contact and kept the spring working length as original. Now I get control of the oil pressure. I can get 8-10 pound on a fast tickover which rises as the revs go up.

Does this sound Ok? It's all a dark art.

Paul

Sounds correct to me Paul: I see about 5lb on tick over when hot but its all over the place when running as my inline gauge isnt damped. Interesting that the seat has recessed so much. I cannot lock the ball down with the adjuster; and it is an adjuster; varying the load on the spring and hence ball in seating. Ive not had a pressure issue in the past so assume it to be correct.

Am welding up the mag platform at the moment after a previous cold stitch repair came adrift. Trust she will be back in good time for the Classic.

Cheers

Jon