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Mercruiser 228 - 305 - engine will not start

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Barney96

Member
1979 Mercruiser 228 - 305 engine

engine will not start - installed new rebuilt carb and a new fuel pump - new fuel/water filter - all lines clear.

When I pour gas into the carb -- engine starts and runs briefly - the same with Quickstart - engine will not start or fire after this.

I see a small amount of gas pumping (looking into the carb) when l pump the throttle.

Does this mean that the float chamber is full of gas ?

It is a Quadrajet Carb - Sierra fuel pump -

Your thoughts are appreciated.
 
yes fresh gas in the tank

Have not checked for a good spark. - The engine fires up when I pour gas down the throat. Could a bad Condenser be a problem

When I look down into the Carb and pump the throttle l see gas squirting but very weak or little. Before I try to start the engine l pump the throttle once - turn key - no fire -- When looking down into the Carb l pump the throttle once, I see a good stream of gas - nothing on the a second or third pump ( Sometimes l only see a little gas squirting)

In order to test the pump l plan to remove the fuel line at the Carb and turn the engine over and see what happens. Is this a reliable test.

This is a Quadrajet Carb and in order to check the air/fuel mixture screw one needs a special tool - I don't have one so l am going to remove the Carb and adjust - would you know the number of turns - 2 or 3

The Carb was installed last year after haul out, and the engine was not started. - The Spark plugs are clean.

Thanks for your help
 
you should see gas squirt from the accelator pump nozzles every time you cycle the throttle...If its only happening once, you don't have enough fuel in the bowl for the carb to deliver enough fuel to keep the engine running...

Are you sure ALL of the fuel lines are clear? did you change the anti-syphon valve? is the vent line open?

better off buying the adjusting tool - if you pull the carb, you should change the base gasket...

be careful pouring gasoline into the carb...it can be very dangerous in a boat if you don't know whats going on...if you insist, you are better off pouring it into a vent than down the throat...
 
If you are speaking about the accelerator pump, then it sounds like the "new rebuilt carb" has an issue...sounds like a warranty claim is in order...

FWIW, the choke (assuming it was adjusted properly) should be able to richen the mixture enough to start the engine...
 
Carb was returned for cleaning Pump works good-? Carb was reinstalled(using same gasket) which was new - cranked engine many times - no gas in carb - loosen the line that feeds into the carb - gas sputtered out - tightened and tried again - no gas to carb Fuel pump is new (could it be low fuel pressure ?- l installed the carb with a lot of care.
 
If you are getting gasoline to the fuel inlet fitting but it isn't filling the float bowl, then the only conclusion I can reach is that somebody butchered the installation of the needle valve andor the float.

who supplied the "new rebuilt carb"?
 
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