Mercruiser 120 Fuel Help

[MS03]

Mercruiser 120. Have good spark. Engine will run on starting fluid. New fuel filters, new fuel pump, and carb rebuilt. Still will only run on starting fluid. Any thing I'm over looking or should try. Thank you.

 

[Scott Danforth]

Is you set the points with a dwell meter? Is your timing correct?

 

[MS03]

Yes dwell was set to 0.022 as listed on the engine and timing is correct

 

[cyclops222]

Well you proved it is not ignition. So it has to be the gasoline or a part in the fuel system. What does each sparkplug look like ? Way to clean and dry ?

 

[alldodge]

When throttle is pushed down do you see fuel squirt down throat of carb?

If not, Disconnect fuel line at carb and see if it pumps fuel into a container

How old is the gas

 

[MS03]

When throttle is pushed down do you see fuel squirt down throat of carb?

If not, Disconnect fuel line at carb and see if it pumps fuel into a container

How old is the gas

Gas is brand new, less than a week old. Spark plugs are new and gapped to 0.035. I will have to find another person to watch the carb to see if it's spraying otherwise I will try to disconnect and will post results.

 

[alldodge]

Gas is brand new, less than a week old. Spark plugs are new and gapped to 0.035. I will have to find another person to watch the carb to see if it's spraying otherwise I will try to disconnect and will post results.

Disconnect the throttle cable at the carb and move it by hand at the carb

 

[Bt Doctur]

and carb rebuilt
??????? needle and seat closed

 

[MS03]

and carb rebuilt
??????? needle and seat closed

Yes, tested before install with no issues

 

[Scott Danforth]

Dwell is not .022. that is the rough gap. Dwell is 34 degrees

If dwell is off, coil saturation time is off and timing is off.

I would tighten your rough gap to .018-0.020 and it will run a bit better.

You probably did not file the points, so your rough gap is already different than what you set it to

 

[cyclops222]

Is there a large fuel filter somewhere ? That was replaced ? It can take a LOT of starter cranking to refill it and the line to the carburetor.