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1977 Merc 402 carb problem

C

chriscraft

Member
My Merc 402 won't start and when I prime it, gas runs out of the bottom of the carb. It sure seems like the float is stuck shut but I'm not sure it is a float style carb.
ANy thoughts?

Thanks,
Mark
 
Many carbs leak when primed since you can build 15 psi with the bulb where the fuel pump makes less than 5.

Pull the plugs, run it over to blow out any gas, then install NEW plugs. Pump the bulb just until you hear it stop making that oozing sound, and try to start it, taking it easy on the choke. And give it more throttle--Mercs like lots of throttle to cold start.

Jeff
 
Hi Jeff,
I just got back around to work on this problem. I took the carb off, cleaned it (it wasnt very dirty) I blew out all the passageways and put it back on. The needle valve wasn't stuck and worked properly. It still won't start. After priming, cranking and choking, the plugs seem to have very little gas on them. Almost like a film. They should be saturated I would think. I have plenty of compression (over 150 top and bottom) and the spark is good.
Is there a filter someplace in line that might be plugged?

Thanks ,

Mark
 
..."I took the carb off, cleaned it "

Swell, but did you take it ALL apart and let it soak overnight in carb cleaner? That's the only way to "clean" a carb.

Jeff
 
Jeff,
I finally got it started. It was flooded really bad. The problem I have now is that it won't start back up with out changing the spark plugs. I followed the manual and set the idle mix screw at 1 1/4 turns. Should I be using a hotter plug than the manual calls for (L76V) ? Bear in mind that this motor ran pretty good last summer.
 
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