120HP Merc i/o no go

skippy116

Cadet
Joined
Jul 17, 2005
Messages
11
I recently had a valve job done. I got the thing back started it up beautifully with no throttle or nothing. It purred like a kitten in idle for about 90 seconds and then quietly died.<br /><br />I cannot get the beast to run now. I took it back to the mechanic who did the work, and he says he can get it running on an external tank, but not on the built in tank. He told me its a problem with the fuel line and I should look at myself to save $ cause its probably a simple thing. Fine, I agreed. <br /><br />He suggested taking off the line just before the fuel pump and suck with a bulb to see if I can get fuel. I did so, and it flowed perfectly with no problems.<br /> <br />I next figured the guy must have had the external tank above the carb (like rested on the deck) and gravity was working whereas my fuel pump was not. The mechanic said the external tank was on the floor, but nevertheless, I disconnected the fuel line after the pump and before the carb and turned the engine over. There was fuel flowing, but I'm not sure if the flow rate was fast enough. I'll get back to this...<br /><br />Next I wondered if the carb was working. I cranked the throttle back and forth, and gas squirted into the carb until no more gas was coming out. I turned over the engine a bit to replenish the carb with fuel and again cranked the throttle back and forth- more gas squirted out. <br /> <br />So now I'm stumped. I already checked the spark from the coil, and its all good. I have all new plugs. The mechanic said it was timed when the valve job was done.<br /> <br />Now back to the fuel rate problem, when I had it into the mechanic last, the guy had to squirt fuel into the carb to get it to start. Presumably he figured there was air in the fuel line, and to short cut past it, he'd squirt a little in the carb to get it running. I've tried doing this too with little more than a burp or a fart before it dies again and won't go.<br /> <br />Could it be the rate of fuel flow? what instrument do I need to test this? Could it be a problem with the automatic choke? The butterfly valve in the carb hangs open all the time. Shouldn't it be closed when the engine is cold? Anything else to try? Serial # is 3886441 if that matters
 
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