Hi I have a 2.3l omc ...im New at this...I'm trying to get the engine to run I put brand-new spark plugs and carburetor but for some reason when I tried to start it it starts to blow gas out of the carburetor I to spak plugs out to check for compression it seems like the exhaust is sucking in air and coming out of the carburetor when I turn the engine the opposite direction manually seems to work fine ..any thought on this?