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Charles, Marine Mechanic
Category: Boat
Satisfied Customers: 3981
Experience:  US Navy (Ret) Certified Mercury Marine Tech with over a decade of repair experience.
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I have a 2010 75 optimax the fuel hose disconnected from the

Customer Question

i have a 2010 75 optimax the fuel hose disconnected from the tank while riding it pulled all the fuel out of the hose killing the engine i reconnected it pumped the bulb and tried to start the engine it would not idle or stay running any suggestions?
Submitted: 1 year ago.
Category: Boat
Expert:  Charles replied 1 year ago.

Hello, my name is***** will assist you.

You more than likely have air in the fuel system. Continued starting should force it all out. Or you can key up the engine, depress the center of the schreader valve on the fuel rail, bleed it, turn the key off and back on, depress the valve again. After a few times, you should get good fuel from it.

Customer: replied 1 year ago.
tried that got fuel coming out but engine won't start its poping like it wants to but just won't fire up would a bad air compressor cause this?
Expert:  Charles replied 1 year ago.

A bad compressor , it should still idle.

Have you checked the fuel for water yet?

Customer: replied 1 year ago.
also removed both fuel pumps and tested them i do notice the engine is smoking a lot when its trying to start
Expert:  Charles replied 1 year ago.

Did you reset break-in, by moving the shifter into FWD and back to Neutral several times?

Expert:  Charles replied 1 year ago.

Also, do you have a gauge that can read up to 120 PSI and screw onto the schreader valves?

Customer: replied 1 year ago.
no did not reset break in and i don't have a gauge but i will get one tomorrow what psi should it read at the valves?
Expert:  Charles replied 1 year ago.

There are a few tests to do. First is at the back of the VST. It should read 25 PSI at key up. Then move to the Fuel rail. Fuel pressure at key up should be 40 PSI, then drop and hold between 10-20. Cranking pressure will get up to 90 PSI. Air pressure cranking is 80.

Customer: replied 1 year ago.
Ok I will try that tomorrow. If all that checks out good what would be my next step?
Expert:  Charles replied 1 year ago.

Spark out out test using an adjustable gap tool. and compression.