mystery problem

[ryanr623]

I posted a while back regarding my boat dying on the water. It shut off just like someone turned off the key. Well I figured it was a spark issue/ignition issue. Nope. Spark from coil. Not as strong as i'd like but the battery is a little low.

I then checked for fuel. No fuel coming out of the carb. Carburetor was dry, pumping nothing. Disconnected fuel hose at the carb, and it pumped fuel like crazy. So fuel was getting to the carb, but not into the manifold.

So stuck float or blockage right? Nope. Took the carb out, replaced some gaskets, hooked it up to fuel, pumped the accelerator pump.... and a nice Y shaped stream of fuel came out.

I am at a total loss. I have no idea what is wrong. I thought the pump was bad, but it obviously isn't. Any ideas? I also tested the fuel for water, and none in it.

 

[Alpheus]

Re: mystery problem

On what???

 

[Ira Quirke]

Re: mystery problem

I had a problem like this some time ago on a motor car. what happened was that the web in the carby that holds the venturi in place had come loose and the engine was not able to suck fuel into the manifold. have a close hard look at the inside of the barrels of your carby. The problem is likely to be there, or at least a blockage in the suction line between the bowl and the venturi..Cheers, Ira

 

[ryanr623]

Re: mystery problem

On what???

1982 mercruiser 120

I had a problem like this some time ago on a motor car. what happened was that the web in the carby that holds the venturi in place had come loose and the engine was not able to suck fuel into the manifold. have a close hard look at the inside of the barrels of your carby. The problem is likely to be there, or at least a blockage in the suction line between the bowl and the venturi..Cheers, Ira

thanks i'll check it out, wont be back in town till monday.

 

[gozierdt]

Re: mystery problem

I've got a '57 T-bird (auto) with similar problems. Turns out the float valve needle is sticking in the carb. The weight of the float is not enough to pull the needle valve down to let fuel into the bowl. I put in an electric fuel pump and pressure regulator, but I'm still playing around with it. Not sure you have the same problem, but it could explain the dry float chamber. I'm thinking that not using the car often enough may have set up a "sticky" condition on the needle valve?

You say you took the carb out, and got good streams out of the accelerator jets. But what happened when you tried to start the engine? Did it start, run for a while and die, or???

 

[Alpheus]

Re: mystery problem

Did you ever check the fuel pressure? Just because its getting fuel to the bowl doesn't mean its up to par as far as keeping it full while the engine is under load.

After you get the engine turning over and have fuel shooting in there while pumping the throttle is it still not starting?

 

[ryanr623]

Re: mystery problem

Did you ever check the fuel pressure? Just because its getting fuel to the bowl doesn't mean its up to par as far as keeping it full while the engine is under load.

After you get the engine turning over and have fuel shooting in there while pumping the throttle is it still not starting?

After she died on me, It was never getting fuel, and I pumped the throttle and tried starting the engine A LOT. Intake manifold was dry as a bone. I have not put her back on yet. Maybe taking it off I freed the needle or float?