Gary - yes I installed an electric pump. Makes for less cranking in the winter when you're trying to get to work.

They are right, plus mine is older than yours.

 

i ve got the same problem Volcano Carb !
I was pulling hair out...there's not much left!

I checked rechecked float / metering rod etc.

I have the original fuel pump on my 85 f250 300-6.

how does it regulate the pressure ?

also my yfa doent have a check ball or the little black hose from the accelerator pump. works fine.
?

 

I bought a pump today will install tomorrow and see if that was the culprit

 

The pump has a spring that lifts the pumping diaphragm away from the actuator lever when there is a head pressure created by pumping against the needle and seat. The pump doesn't really regulate the pressure it just doesn't pump. Do you have gasoline present in the crankcase oil?
Take care.

 

Nope oil is good !

 

What is your definition of "regulation" of pressure? However they are doing it, it is regulating the pressure I would think, even if it's putting the pump in "neutral gear" so to speak.

 

Nope oil is good !

 

Correct. Just sometimes I think of regulation as a "calibrated leak".....not necessarily a no pump situation. Just my opinion.....Here is something funny for those reading the thread. The "latest" returnless fuel systems don't operate too differently. More technology of course but a lot of the same principles. These systems don't use a fuel regulator either. Instead they use the feedback from the FRP sensor (and several others) to determine output demand for the fuel pump. Interesting stuff. Take care.

Cliff

 

New fuel pump and filter STILL same issue. Next week I will get a fuel pressure vacuum tester tool and see what my pressure is. If I didn't have all papers and original build sheet on the truck I'd scrap it at this point lol

 

I wouldn't scrap it because of fuel delivery issue. Retrace your steps. It will be something simple.

 

Mechanicals don't regulate, they pump the same PSI continuously until you punch it in which case the faster pumping (I think) would increase the quantity and gas to meet the need of the engine. The only way to change PSI is if you had a different pump. I can adjust my pump because it's electric and I built in a regulator.

You can't scrap it. You're just having old truck problems. Once you get through it, you'll be the happiest guy in the world. Especially when you catch that dude on the interstate checking your truck out!!! From what I can figure out, volcano carb is occurring because fuel is flowing uncontrolled into the bowl and out of places it should not be flowing. So its got to be fuel PSI, needle, float sinking, wrong float adjustment, the little doohickey the needle seals against.......and that's all I can think of right now.

 

Cliff is right. With Carburetors 99% of the problems you have make you feel like a total loser once you've cured them. You wanna stamp the big "L" in the middle of your forehead to save people the trouble. And in my case, you usually end up with a lot of spare parts you thought were busted which come in handy down the road.

 

I agree carbs are really really sensitive to the slightest dust or contamination. They are deceptively simple, yet extremely precisely calibrated machines. 1 mm of dust in the right spot can ruin the entire carburator operation.

 

Great !
Not.
standingby
or maybe ill just put my old 2 barrel on
i know its good!

But it needs the plastic fast idle cam
356 cfm

 

X2...this will be something simple.