fuel pump with too much pressure

dustof45 · #1 (**permalink**) 05-14-2004, 08:40 PM

Hey,
I have a 1939 flathead v8 in my 45 ford pickup and the fuel pump is pumping with way too much presure. It's pumping at 9psi where it should be pumping around 4.5. Im not sure what to do to regulate that, besides buy a regulator, but why would it be pumping like that? There havent been any modifications. The engine is stock. The only thing i can think of is that the guy i bought it from and a washer on each side to space the fuel pump away from the oil vent. But that isnt the way it should be. Any suggestions?

dustof45 · #2 (**permalink**) 05-14-2004, 10:29 PM

it also looks like the fuel pump is not pumping right either. From all the pictures i can find for a '39 fuel pump, the fuel line from the gas tank should hook up to the fuel pump where it says "in" and then the other side goes to the carburetor. On my engine it is set up so that the fuel line from the tank goes to the opposite side, not the side that says 'in'. This is how it was set up when i bought it...

dustof45 · #3 (**permalink**) 05-28-2004, 12:17 AM

Just as a reference for anyone who runs into this problem later on... since no one evidently has yet, since there were no replys. Who ever rebuilt my flathead engine, did a horrible job. They placed the valves backwards in the fuel pump. They also lengthened the push rod by a quarter of an inch or more. I'm not sure what they were thinking, but it left me with several days of frustration and a broken rocker arm on my new fuel pump.. But its all working now and it idles fine...

46yblock · #4 (**permalink**) 05-28-2004, 12:41 AM

I would say that you are a good mechanic and great troubleshooter!

mtflat · #5 (**permalink**) 05-28-2004, 12:50 AM

Thanks for taking time to post your solution. I didn't have a clue about a fix for the problem. I have reached the place where I mistrust anything I haven't personally repaired. You just never know what shortcuts the last guy may have taken.............

46yblock · #6 (**permalink**) 05-28-2004, 01:18 AM

mtflat, I reached that place a little more than 10 years ago. Had a 54 1 ton. Shop said they could redo the whole thing and paint. $5,000 later, there was zero oil pressure at idle and the paint looked pretty good at about 150 feet.
If you are not a mechanic, it is never too late to become one.