Over one year later, Betsy is getting the exhaust upgrade she deserves. I discovered the intake was cracked and got that brazed. I also discovered that the manifold bolts were finger tight and the valve cover gasket was gone. Betsy is soon going to feel all the power to the wheels she was pushing out her cracks and gaps!!!
The Crane truck max cams make impressive low end torque that is real world handy in a truck. Hooker has a header for the 300 as well. I built one of these ages ago. Since you guys bumped this thread I read all 8 pages. Clifford Performance has intake stuff.
Put in EFI manifolds. Some say it may give me another 20HP to the wheels. Of course now the carb is leaking all over the place. I suspected a stuck float but that was not it. Took it apart, cleaned it, back on same thing.
I bought a Chinese Amazon carb to replace the old beat one. I am sure I wil get flamed on the Ford forum.
Brazed the cracks and decked the manifold with a sander.
Remflex FTW and new Dorman studs and a new valve cover gasket. I went ahead an put bolts in all 8 holes
Mounting it all up.
All back together before the gasoline leak was detected.
Leaking under from the carb. I think where the accelerator butterfly goes through in the venturi. So I think that the needle and seat is jacked allowing a ton of gas to flow through and just run out of the throttle shutter's pivot. I really can't tell. I took the top off the carb to see of it was full of trash and it was clean but all the manipulating of the manifolds when I had it off and the carb was still on it has to have had something to do with it.
I attached the 2 1/2 Y pipe to the old 2" exhaust. one day I will get that replaced. I also still need to replace the front brake lines.
I got the brand new carb installed. Same thing. Leaking a ton of gas. The carb was bouncing around in the shipping box so certainly it could be possible that the float is sticking or the needle and seat are buggered. I had thought maybe it was a back pressure issue but the truck is running so good it can not be something in the Y pipe. Plus the first time it happened the Y pipe was not hooked up tot he rest of the exhaust.
I am going to pick up a cheapo fuel pressure guage. I am going to pull some of my vacuum.lines and see if that alters anything. Then I will pull the carb and inspect the needle and seat in the new carb. Needle and seat in the old carb looked fine.
Can too much vacuum suck gas into the base of the carb at such a rate it overwhelms it? I can not see how I would have the exact same issue with an old and new carb unless the issue was not the carb at all.
Hmmm, interesting. It's gotta be something in the carb. When you say new and old carb, is that new new and old new or new new and old old? (This is the 2nd replacement unit correct?)
Unless the pressure is excessive, I can't imagine it's "forcing" too much fuel in. It's just odd that the same issue is occurring across all carb attempts, so I see why you suspect the culprit is elsewhere.
Old carb - the one that came with it when I got it from you. New - brand new from Amazon cheap South America carb. I have bad carb luck. The carb I got from Marshall for my 40 years ago leaked like a f$cker and he replaced it. It would not be weird for the needle and seat to go crappy in the old crab and be $hitty in the new carb becasue of luck.