OS 120 III pump help!
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Hello, I have a OS120 III (Pump) 4 stroker that since day one has not been able to prime itself without choking the engine. In addition, It requires the needle valve to be opened significantly more than what is suggested in the manual. Since the engine is cowled in, it is impossible to choke the engine.
As a side note, I don't run muffler pressure
This appears to be a leak or a poor performing fuel pump. Ironically, once the engine is running, it runs very well (with the needle opened more than it should be.
Can you offer any suggestions to fix?
Jim
As a side note, I don't run muffler pressure
This appears to be a leak or a poor performing fuel pump. Ironically, once the engine is running, it runs very well (with the needle opened more than it should be.
Can you offer any suggestions to fix?
Jim
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If you can't choke the engine, then the only way to get it going would be to use an electric starter and spin it until it drew enough fuel to start.
As far as an leaking may be concerned, if you're getting a lot of raw fuel inside the cowling, then we'd suspect a leak in the fuel system.
When you mention that you need the high-speed needle open farther than O.S. states, what do you mean? Where is it being set?
As far as an leaking may be concerned, if you're getting a lot of raw fuel inside the cowling, then we'd suspect a leak in the fuel system.
When you mention that you need the high-speed needle open farther than O.S. states, what do you mean? Where is it being set?