Hi folks!
I have bought a vacuum bagging kit and actually today i started my first vacuum project.
The process is going well but i have two concerns related to the vacuum pump.
There is a lot of oil fumes leaking from the air exit valve. I have my pump working for about 2 hours now and the oil level has dropped lower than the middle point. I must leave the pump working overnight but i am sure that the pump will starve at some point.
Also, can i fit a non-return valve to the circuit so i can switch off the pump as soon as the laminate has built up a certain value of vacuum?
Thanks in advance!
New or used pump?
Mac valve can control the on and off cycles
The pump is brand new!
I now switched off the pump because i am about to run out of oil… A lot of oil fumes inside the workshop too! 
My robinair pump burns oil, but not rapidly. It does burn enough that it will put smoke into the air. It would take at least 40 straight hours or more of operation before the robinair would burn out all the oil or even half the oil.
So that being said, burning oil is normal. Consuming all the oil in less than 24 hours is not normal. I would return the pump and get your money back.
Did you read the instruction manual that might have came with the pump?
Is there a break in time with out a load on it to set the rings/ seals?
Vacuum leak = oily exhaust.
I had a maximum vacuum of -0.4 atm.
There was a lot of oil fumes coming out of the exhaust and actually some oil dripping from the exhaust creating a large blot of oil on the floor… 
You need to pull a full vacuum. Revise your bagging skills and all connectors. Should be seeing the equivalent of 27" or more.
If you have a leak, air will go into and through the pump along with oil.
Attach a cheap fuel filter to the end of the exhaust, this way you’ll stop the leaking and fumes, but you will have to find why the pump is leaking the oil so fast, it’s not normal IMO.