rinkhals01

Hi there.
I would like to know if I can use the VP-22SG Oscillating pump for a nitro to gas conversion on a NIB Magnum 1.2 fs 4st whilst still using the nitro 2 stroke carburetor, as I don't want to adapt the motor casing to accept a walboro carb because I don't have the necessary tooling to make the carb adapter?

Any help would be gratefully received.
many thanks.

mgnostic

The biggest problem will be with the needle valve. You will have to set it quite a bit differently since the engine will burn less gasoline by volume. You will also need to run a higher proportion of oil to gas than is used with larger gas engines due to the magnum having a bushed connecting rod.

rinkhals01

Thank you so much Mgnostic.
Your comment about the needle valve, are you meaning that it is very difficult to tune?

mgnostic

Not so much difficult as different. Methanol burning engines are, relative to gasoline engines, quite the fuel guzzlers. For small engines it's not that big of a deal but once you get into bigger engines you are flowing a significantly greater amount of fuel. I dont remember the exact amount off the top of my head but you need like 50% more methanol than gasoline for efficient combustion. What that means for you is that you will have to close the needle quite a lot more to run on gasoline. If your carb has o-rings they will also need to be gasoline compatible. Since the SG series of pumps are gasoline compatible that part of things should work and substitute for the built in pump in the Walbro type carb.

larry@coyotenet

My Feedback: (21)

First check to see if the Perry pump uses a silicon diaphragm, if it does the gas will ruin it so be careful

rinkhals01

Thanks so much Gents for the great answers.... it's much appreciated.

RichardGee

My Feedback: (156)

My question would be why you are running a fuel pump? IF the fuel tank is placed close behind the engine with its centerline at or slightly below the centerline of the needle, no pump should be necessary... exactly as it works when running glow fuel.
You can also utilize muffler pressure, although some say this can be risky due to the higher volatility of gasoline. Fact is, you would need oxygen to ignite the fuel in the tank and this isn't likely using closed-loop muffler pressure.
My recommendation would be to bench mount your set up and try it to see if you really do need a pump.
And as has been mentioned, you will need a minimum of 20% oil to protect the bushed rod. Best of luck.

rinkhals01

Thank you RichardGee.
You have raised a valid point and I will try on a test bed.