Hey there all you experts out there. Last december I finally got the pickumuptruck i always wanted, the old style roundy round kind. It's a '53 F250, 215 6, 4 onna floor. came as a flatbed, but is bare fanny at the moment, just frame. After making it stop (rebuilt the Master Cylinder), making it go was next. Carb didnt have a air cleaner on it so it was pretty scuzzed up. Gas tank had some funky rust fluid in it too. Didnt even bother to try to run it off the original gas tank. I had a buddy make a fuel cell for me, and ran a new line to the fuel pump. the line from the pump to the Holley 1904 is untouched (so far). I rebuilt the Holley, not that tough a project other than cleaning the bejeebers outta it. Set the float per the kit and an original ford shop manual (9/32"), and put her back on. She fired right up and ran smooth. after about 5 minutes gas started flowing out of the bowl vent where the top bowl screw is. I set the float lower, and tried again, same result. Set the float even lower, one more try with same result, gas coming out the overflow/vent hole in the top of the body side of the float chamber after a couple of minutes of running at idle. I pulled the carb, and checked the new needle and seat. when held upsidedown, the needle seals with just the weight of the float assy. made sure it was all clean and put her back on, same thing. ran for about 5 minutes and then gas started flowing out the vent/overflow. There are new copper washers, new matched seat and needle, and I checked the float for being gasloged. It's dry as a bone, and no bubbles when submerged in water. plenty of boyancy.

I"m gonna put it back on tomorrow and see what happens. as I didnt do anything different, i'm gonna assume it will overflow again after about 5 minutes. Lookin at the fuel pump diagrams, there's no listing for a bypass, or other pressure regulator. my only guess at this point is i'm getting way more than the 4 - 5 pounds out of the pump and it's muscling past the float/needle/seat.

Can anyone shed some light, or offer some suggestions? I dont have a pressure gauge or i'd find a way to get it onto the fuel line between pump and carb somehow.

thanks for any help, it's deeply appreciated.

 

Send an E-mail to ALBUQ F1 (Ross) he's good with these crabs and can probably tell you what's up.

 

You are probably correct with the fuel pump guess. I know the new replacement pumps for the flatties have too much spring pressure, causing them to unseat the needle in the 94s and 97s.

 

from the fuel pump question i posted a day after this post :

Hu Rah! (methinks). I found a reference by chance on the Fordsix Performance forum, did a little more searching and found this. ( FORDSIX PERFORMANCE • View topic - Holley 1904 observations ) After I put my fuel pump back in I took this guy's lead and pulled my carb one more time. took out the new seat from the rebuild kit, cleaned up my old one, and put it in with the new other parts. It seems to have worked overall. After letting it run for 10 minutes, then driving up and down the alley (with the hood up skerrin the neighbors lol) keepin a close eye, no gas pouring out the carb. Not even after I shut the truck off. After the terrorist goes to bed i'll grab my new license plates and take a cruise around the block and hope for the same success.

 

you may nead a pressure regulator, these carbs dont like more than 3 to 3 1/2 pounds of fuel pressure.

 

Preferably 1-1/2 to 2-1/2. Very sensitive.

Dumbluck, that's an excellent link, excellent sleuthing on the part of the poster on that thread! The force on the float/needle is a function of the area of the hole in the seat (Force = pressure x area). So even with the correct fuel pressure, it could be overcoming the float. I'm going to go out on a limb here and suggest chinese outsourcing is a big part of the problem. Does the new needle have a Viton (black rubber) tip, or is it brass?

Many people swear by the carb parts sold by Vintage Speed; I've had good luck with them, too.

 

That was some good detective work. On the 94s I rebuild, I re-use the old steel needle/brass seats. I have 4-5 glass bowl 1904s that will be done some time.

 

the new needle has the newer Viton tip. I've takin a few cruises around the neighborhood with not a drop out the top of the carb. The idle seems fussy, but i know the mixture needle has a slight tweek in the tip, and i havn't messed with it yet. I'll prolly have to stop into NAPA and order a new A/F mixture needle. oh, it didnt help that the idle set screw was missing it's tension spring (DOH)

Got the rest of the air out of the brake lines/rebuilt master cylinder too tonight, and hokey'd up a brake light. I be daylight legal at this point. LOOK OUT WORLD, HERE I COME !!!!! Vroooooooooommmm rumblerumblerumble pop pop pop (no exhaust, yet)