i have a 46 flathead, with rebuilt carb points and condenser and new fuel pump. at idle the car runs like a clock but when a load is put on it it studders, as if it were a fuel delivery problem, it will get fuel until it starves out about a block down the street and will refuse to start until i remove the fuel line and re-install it, i cleaned and resealed the tank and bent up new fuel line and am stumped, please help flathead gods of hot rod past. By the way the engine completely stock

 

Vapor lock?

Red

 

New gas cap? Tank not vented properly (enough). New fuel line (rubber) have a flap inside? Debris left in tank? Not to bash or insult you, but the list is long. OBCB

 

how is the stroke on the pump pushrod? maybe not stroking enough?

 

put an electric pump on it . i did my 53 . the lists the guys have given you are a good place to start . also i just bought and got home a completely stock 52 with a flatty and was having the same issue . turns out the cloth covered line between the main line to the fuel pump had a break in it i couldn't see and was causing me issues . it was sucking air and starving the engine out and killing it under load . i posted a thread with pics of it on the 48-60 forum . it was only a small break till i took it off it fell apart , but it caused the exact same symptoms you are reporting .

 

while its running if i remove the gas cap i have no difference it still runs out of fuel, i bought an electric fuel pump to install just havent had the chance yet, ol cowboy i appreciate your comments but ive been up and down that list and it appears to be sumthin else, SOSOTWO, would it even run at idle if the fuelpump pushrod wasnt stroking enough? and u mr 55 350, that fuel pump made that big of a difference? im going to throw it on today and see if it help, thank you all and keep me poste if you think of anything else!

 

yep the electric pump made a huge diff on my 53 ! i had too put a regulator screwed all the way down to 2.5 lbs of pressure on it too .if you run more than 4 lbs it'll force fuel out of places you didn't know that it went too !!!!!!!!! as of now i'm having all sorts of fuel delivery issues with the 52 customline ,adn it's either more garbage in the tank or the pump is shot despite having been put on new 5 years ago by stan lomelino , mr. flathead here ;bouts . if it's the pump the 52 despite being 100 % original is going to get a 6 volt electric so it can be driven and used without issues including the vapor lock i have experienced with the truck !!! heres the two rides i speak of , and go electric your flatty will love you for it and it sure cleans up the looks of the back of the intakes on 'em !!!!!Attachment 24780

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