Loss of fuel under throttle.

MightyMats said:
Good Evening all. This pertains to the 440 in my 67 Chrysler. Stock rebuild with a very mild cam and a msd pro billet distributor and msd box.

The short of it is that I have a fuel issue at all speeds where I just seem to run out of fuel in the bowls and the car surges under load. The issue is intermittent and sometimes I have to manually fill the bowls up through the vent tube because cranking the engine doesn't get fuel into the bowls.

Two months ago I drove from Boston to Norfolk VA for work. Stayed there for 2 months, drove aound, no issues besides my ignitjon coil going bad. I then drove down to Jacksonville FL last week.

Halfway down to Jacksonville my engine started to surge at 75mph under throttle. Thought it was weird, couldn't fix it so I continued my drive because of a timeline i had to meet. Drove it until that night when it died on the on ramp and would not start back up. Had it towed and replaced my fuel pump the next day because I thought that's what it was "no fuel in the bowls." I also checked the needle and seat, there was some gunk in there.

I thought it was fixed but it wasn't. Made it to Florida though. I have been here a weeek and cant figure out wtf is going on. It is definitely a fuel issue. When the car dies and doesn't want to start I dump fuel from a Jerry can down the carb and it starts then it just dies. I have to manually fill the bowls through the vent tubs when it's acting up and it usually gets me back to base...

I have a FST carb (850 w/ vacuum secondaries) that I took apart last weekend and did only a thorough cleaning, found a bit of wire in one of the jets, I thought that was the issue... nope still surges but the 440 runs better now.

My gut tells me this is a bad needle and seat. Like the seat is getting stuck closed not letting fuel into the front bowl. This may explain why it's an intermittent issue. Thoughts?
Click to expand...
Did you check the fuel filter?
 
MightyMats said:
I swapped the bowls and made it home. Had to remove the power valve linkage. It was a **** show. On the side of the road for too long..

Not sure if I'm going to keep this or throw it in the garbage. But thank you for all the help.
Click to expand...
Rebuilt junk is still junk.
I vote FST in TRASH
 
Put the carb on Craigslist (or similar) and sell it to recoup come of your "low mileage" cost.
 
I have good news and bad news. I think I found out what the issue is... bad news is, it might suck fixing it.

I threw the new 750 carb on the car this weekend (saturday)and it ran great. Ran a whole bunch of errands, hit the gym, went our for Halloween weekend. And then the problem came back. The new carb didn't fix the issue.

But it ran good for a day which means it isn't the fuel limes going back to the tank. My problem is now narrowed down to the fuel pump push rod, or the cam lobe.

Tonight as I limped the car back to base. I decided to Rev it and watch the fuel in the bowls. It sucked the fuel right down but was slow to fill the bowls up. Which is why under heavy throttle the issue comes up and persists for awhile before going away. The bowls are trying to fill back up but they can't.

Put a wooden drumstick to the fuel pump and I can feel it ticking as it's running. So I am going to pick up a new push rod and pray to God that the new and old pushrod don't match in length because then that means the cam is ****.

It's all starting to make sense. More to follow
 
If the cam shaft was wiped out, the problem would not be intermittent, as you stated it ran great most of the day. When replacing the fuel pump shaft, get someone to help bump the engine over and confirm the travel on the fuel pump shaft is close to the camshaft specs. Pull the coil wire so the engine does not try to start.
 
Last edited:
MightyMats said:
Good Evening all. This pertains to the 440 in my 67 Chrysler. Stock rebuild with a very mild cam and a msd pro billet distributor and msd box.

The short of it is that I have a fuel issue at all speeds where I just seem to run out of fuel in the bowls and the car surges under load. The issue is intermittent and sometimes I have to manually fill the bowls up through the vent tube because cranking the engine doesn't get fuel into the bowls.

Two months ago I drove from Boston to Norfolk VA for work. Stayed there for 2 months, drove aound, no issues besides my ignitjon coil going bad. I then drove down to Jacksonville FL last week.

Halfway down to Jacksonville my engine started to surge at 75mph under throttle. Thought it was weird, couldn't fix it so I continued my drive because of a timeline i had to meet. Drove it until that night when it died on the on ramp and would not start back up. Had it towed and replaced my fuel pump the next day because I thought that's what it was "no fuel in the bowls." I also checked the needle and seat, there was some gunk in there.

I thought it was fixed but it wasn't. Made it to Florida though. I have been here a weeek and cant figure out wtf is going on. It is definitely a fuel issue. When the car dies and doesn't want to start I dump fuel from a Jerry can down the carb and it starts then it just dies. I have to manually fill the bowls through the vent tubs when it's acting up and it usually gets me back to base...

I have a FST carb (850 w/ vacuum secondaries) that I took apart last weekend and did only a thorough cleaning, found a bit of wire in one of the jets, I thought that was the issue... nope still surges but the 440 runs better now.

My gut tells me this is a bad needle and seat. Like the seat is getting stuck closed not letting fuel into the front bowl. This may explain why it's an intermittent issue. Thoughts?
Click to expand...
what fuel filter r useing ? have u dont a volume test? how long dose it take for u yo pump a qt of gas ino a bottle? 30 sec or less? if so u have enough gas if not checkthec fuel pump rod they do ware out
 
ill he honest, i thought it was fixed with new fuel line. everything was great, then a few days later the problem came back.

i went to Napa, bought and wired an electric fuel pump to run off 12v switched key power and everything is now fine.

my wife was coming to town and i didnt have time to tear into the motor so i just went with the electric pump. been working fine for three or four weeks now. ill figure out what the issue was later.
 
well her is the issue u will have with a electric fuel pump . u c when i was buildong my polara i put 1 street pump @ he tanl & a race mechanical on the block, i shoould had revercided it . 2 race carters @ the tank & a street/ stock mechanical on thr block , cause 2 yrs of running the hell out of it the motor stoped dead on the road . i had to get it towed home . i had no gas in my profikter the electric pmp quit / i had suced it dry . after talking to a couple of racing buddies i put 2 35 gal /hr by the tank & stock mechanical on thee block i let it regulate the fuel to the carb . i ran thart set up for 15 more yrs with np. now i addred a ho-made cooling can up by the froont with insulation aroundthe outsidec. i filled the "can "with ice when i was racing on a hot day in the 180's mopar added a return line to the tank to stop the vapor locking issues they was avibng on the hot rinnng small blocks with the 195 degree thermostats
i ould put 2 eletric pumps near the tank & letthe stok one as is on rhe block . its not hard to remove te push rodwith a magnet pik up tool we did ours in the driveway & then packed the placete riod went into the block with vassoline & put te pump back on
on my 440 my rod wasc 7/16-3/8 of a inche shorter . i went oyut to my budy clay & he told me to try the rod the oher thing is a worn lobon the cam . then i replace the cam or go to a opair of eletric pumps thats yur chooises i feal
 
stubs300 said:
You should talk because you sure as hell can't type or do spellcheck, I can't understand what you're sayin!
Click to expand...
my email is ka0mek at sbcglobal.net . email me & i will give u my # if u use a electric pump make sure u dont suck it dry as u will damage it . use 2 @ the tank to the stock one on the block & let it regulate the flow to the carb i made the mistake f not having enough flow & damaging the electric pump. . the rule of thumb is use electric to mechanical or electric to a regulator . or u may over fill the carb causing over filling issues
 
Hey Mighty Mats,
Just checking in on this thread.
Assuming all the dust has settled on this one.
Did you ever confirm beyond all doubt what the culprit was?

Thanks,
Mike
 
stubs300 said:
You should talk because you sure as hell can't type or do spellcheck, I can't understand what you're sayin!
Click to expand...
well spell check only works when the spelling is close & u r right my spelling & typing is bad . i heat texting& typing i would much rather talk . in a few minutes i can say what would take me 2 paragraphs to type i hunt & peck im a 1 finger typer
 
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