R2 Oil from fuelpump to blower and to carb.

[Leo B]

About Avanti R2.  I have a closed fuel pump (as R2 should be, as I understand it, without ventilation) to which I have connected the Paxton hose. There is pressure on the hose from the Paxton (I have checked).
Now the problem is that the oil gets from the top of the fuel pump through the supercharger connection to the carburetor. Where's the problem? Is there too much oil in the timing gear cover that travels up through the pump to the supercharger connection? Have I connected correctly? I can't tell if it only runs at low revs.

Edit: I have a new R2 pump and the seal on top of the spring should be fine. Maybe not after all. How can oil get on the pump diaphragm?
Do I need new better rebuilt kit?

Edited August 17 by Leo B

[mfg]

Does the supercharger maintain its oil level? Sometimes a worn Paxton will throw a bit of its lubricant into carb.

[Leo B]

1 minute ago, mfg said:

Does the supercharger maintain its oil level? Sometimes a worn Paxton will throw a bit of its lubricant into carb.

The engine oil is from fuel pump. I see this when I disconnet the hose from the pump. My conclusion is that the oil gets onto the pump diaphragm through the pump diaphragm spring seal. I can't think of anything else. Isn't there a lot of oil pressure in the timing gear cover?

[Leo B]

1 minute ago, Leo B said:

The engine oil is from fuel pump. I see this when I disconnet the hose between the pump and Paxton. My conclusion is that the oil gets onto the pump diaphragm through the pump diaphragm spring seal. I can't think of anything else. Isn't there a lot of oil pressure in the timing gear cover?

 

Edited August 17 by Leo B

[John C]

Hello Leo,

          I would pull the fuel pump and take it apart. I think you have a bad diaphragm. If it is not that the source of the issue seems to be in the pump from what I can gather so you should find the problem.                                                                                                                                     Best of luck, John C.

[Leo B]

Thank you John C, I opened the pump and I think the leak is coming from the stem seal, which has a gaping hole for the stem. Need to by new repair kit.

[Leo B]

Problem solved. PCV Valve (Positive Crankcase Ventilation) was stuck and this created pressure in the crankcase (and oil pan) and thus also to the fuel pump. After cleaning PCV Valve all ok.
Workshop Manual use word "Check Valve".
Thank you all 😉👍
 

[Nelson]

Can a PCV really reduce the pressure in a crankcase by that much? It seems like it would be no match for the valve cover breathers. Do you theorize the valve was stuck open allowing pressure from the blower to increase pressure n the crankcase?

Edited August 26 by Nelson

[Leo B]

19 minutes ago, Nelson said:

Can a PCV really reduce the pressure in a crankcase by that much? It seems like it would be no match for the valve cover breathers. Do you theorize the valve was stuck open allowing pressure from the blower to increase pressure n the crankcase?

The oil leak disappeared completely when I cleaned the valve. It's a shame because now I can't remember which way it was stuck. In any case, it was stuck and didn't rattle at all and created an overpressure in the crankcase.

[Leo B]

11 hours ago, Nelson said:

Can a PCV really reduce the pressure in a crankcase by that much? It seems like it would be no match for the valve cover breathers. Do you theorize the valve was stuck open allowing pressure from the blower to increase pressure n the crankcase?

Now that I think about it, I'm pretty sure the valve was closed the whole time. If it gets stuck, the tip of the needle is probably stuck. You can test how strong the flow is in the intake manifold/valve by disconnecting the hose. It sucks plenty of air from the crankcase.
I guess that many people do not service the valve from time to time and think that the cause of the oil leak is something else. The valve gets blocked because the air it sucks in is oil mist.