351 winsor stalled after 10 minutes

[carlobo]

Hey, I have been rebuilding my 1970 bronco, I bought it with a professionally rebuilt 350 winsor, it was running great.

I tore the bronco apart to do some repairs (everything except the engine and tranny), and about a year later got it back together.

I did not treat the gas, so it did go bad in the tank and gum up my carb. It ran poorly if I could get it running at all, so I did a carburetor rebuild kit (Holley street carb) and it was running awesome, better than it even did before. However, when I got about a mile down the road it started to sputter and died on me. If I waited a couple minutes I could get 30-40 feet out of it and it would die again. I checked for gas in the tank and noticed it had pulled a vacuum in the tank, thinking it would run with the cap off, I jumped back in, but it was still the same, once I finally worked it back to my driveway I idled into my street and it began idling just fine. So I tried to take it back out but as soon as I got on it, it was just more of the same.

I have just installed a brand new fuel pump rated for a motor of this size. If I leave it for a while it will start back up and run for a while but seems to slowly begin bogging down until it is essentially dead.

Any help would be greatly appreciated!

 

[Rons beast]

Did you clean the tank? Sounds like gunk is clogging the filter. Check the fuel filter.

Let us know what you find. The info is benefiticial to other forum viewers.

Good Luck

 

[Bully Bob]

Hi., & welcome..!!

Yep.., that has all the earmarkings of a restriction., most likely at the fuel pick-up tube in the tank. It has a screen on it & is likely plugged with goo. Or junk floating 'round in the tank attaches with suction & releases when eng. is off.

You'll have to pull the sending unit & check.

Then it's necessary to clean the whole fuel system...carb. again., fuel lines., fuel pump., & flush tank.

If not., you'll likely repeat the prob. time & again.

If the rubber lines are old... this is a good time to get new quality rubber.

Put a see-thru filt. B4 the fuel pump & another B4 the carb.

Like Ron says., it could be the filter is clogged., but it had to come fr. somewhere.

I actually cut those metal filters in half to get a clue as to what's in the system.

Ya., do let us know what you find, if you would.

 

[Scodge]

I had that same problem, and it was a bad fuel pump. Check your fuel pressure. My pump was making enough pressure to keep the bowls full at idle, but once I began driving, I'd run out of gas, even though the tank was full. Install an inline fuel pressure valve, and see what kind of pressure your getting at idle. Should be 4-7 psi.

 

[monza]

Put a see-thru filt. B4 the fuel pump & another B4 the carb.

I used to have a ton of issues fueling my 351.

Putting a see thru filter before the carb made it MUCH MUCH easier diagnosing.

It takes a whole bunch of guesswork out of the equation when u can see the fuel level - and see the pump surging - The glass tube is your friend - get one.

FYI:

I ended up resolving my fueling by installing a new 25gal rear tank, pick up, sensor and fuel lines.

I also bypassed the side tank which was wired to the wrong side of the gauge switch - so i was reading the full tank - but running on the empty - if it werent for the see thru filter I might still be scratching my head on that one...

Good luck.

Monza >-