126 '84 500sel

Hello,
I have an '84 500 SEL. The car sat for years without running. I purged the fuel tank, installed a new fuel pump, fuel filter, plugs and changed the oil. After a few adjustments and a hot battery, I got the car running. However, in about 10 minutes, while I was allowing the car to burn off old fuel, etc, it began to pump fuel out the air cleaner hose. ( I had the air cleaner removed) What might cause this?? Perhaps my cold start injector stuck open? or is their a line on the fuel distributor that could be clogged? your insight would be greatly appreciated.