trouble with 1989 120 hp johnson

[phillipay]

I have a 1989 120 hp johnson. the only way i can keep it running is to hold the choke in or force fuel to the fuel pump by squeezing the bubble. i have put on a new power pack, new stater, replaced the metal tank with plastic, replaced all fuel lines, had carbs cleaned twice, new fuel filter, disabled the automatic oiler and started premixing, new key switch, have a compression of 127 on all cylinders, has very good fire. i have had trouble out of this motor since spring of 2009. have narrowed it down to the vro2. any suggestions? i am about to give up!

 

[klrbruce]

Re: trouble with 1989 120 hp johnson

Fuel pump? Gas tank vent?

 

[ezeke]

Re: trouble with 1989 120 hp johnson

If you can keep the engine running just by using the primer solenoid, the fuel pump is working. The primer solenoid is just a valve, it relies on pressurized fuel from the fuel pump, (or from the primer bulb if you keep squeezing it).

Have you rebuilt the carburetors and synchronized?

 

[phillipay]

Re: trouble with 1989 120 hp johnson

I have had the carbs cleaned twice, but not rebuilt. The mechanic that cleaned them said they looked like new. They have also been synchronized. The motor starts very easily, but acts like it is running out of fuel or not getting enough fuel and shutting off after only 4 or 5 seconds. The primer stays pressurized, but if I squeeze it real hard it seems to force fuel to the motor and keep it running longer. It will also run longer if I hold the choke in, but it eventually floods out. The gas tank is also well ventilated. All fuel lines have been replaced with new ones. Any suggestions will be greatly appreciated.