Newbie 4350 Carb Question

[Lambsfoot]

First post here so please be gentle if this is well worn topic. I have a '76 Wagoneer with the 401 and Motorcraft 4350 that will only start if I squirt starter fluid into the carb. The carb has been rebuilt and I stripped it this past weekend and could not see anything wrong to my eye. The plunger seal looked good and I blew out all the orifices. Any thoughts?
Thanks,
Kevin
Long Beach

[Stuka]

Its a common issue with 4350's. I never did fully solve it on mine. If the truck sat for more than a few hours, I had to pump fuel back up into the carb. The plunger is not the issue. The issue is the fuel escape (evaporates) out of the float bowl. So if you turn it over enough, it will start up.

I ended up switch over to an edelbrock intake and crb later on and never looked back. Got better performance and fuel economy. Plus it always started perfectly.

[haminawag]

Make certain the accelerator pump is forcing gas into the squirters so that when you're looking down the throat of the non-running engine you can rotate the throttle all the way back and confirm that you're getting 2 healthy squirts of gas from the nozzles, the float bowl will have to be full of fuel of course to do this. Then run the engine normally, shut it off, let it sit so that you're sure it'll not want to restart easily, then repeat the above squirter test. If there's no gas coming out of them then you know for sure the float bowl is emptying itself out somehow. One way is through drain-back through the fuel supply hose between the carb. and the fuel pump. Another way is through the ball-check valve inside the carb., these are sometimes replaced by people with a smaller or larger ball bearing, either way it'll prevent the float bowl from being sealed off, also sometimes that ball bearing gets old, nasty gasoline schellac on it and it won't seal. The ball-check weight is often missing too. I would recommend a thourough rebuild with a quality kit and a full inspection of all the fuel hoses and such. Even a cracked float bowl can do it.