Ford 351 carb

catfishblues

catfishblues

Well-Known Member
Joined
Jul 26, 2005
Location
Pfafftown, NC
A buddy has a mid-80s Ford short bus with a carbed 351. It keeps laying down on hum, and I'm trying to find him someone in Winston who is pretty good with these emissions choked vacuum-line-spaghetti beasts. It's a food truck and he couldn't make it to a gig yesterday because of it. The shop he's been taking it to seem like pretty good guys, but I don't think they know carbs at all. Anybody here have any suggestions?
 
Mid 80's? Is it not old enough for Safety only inspection? Strip that thing and simplify. I bet it's vacume related somewhere.
 
What exactly is it doing?

Sent from my XT1254 using Tapatalk
 
And what carb is it? 2bbl, 4bbl (Ford or Holley) or is it that God awful abomination variable venturi carb

Sent from my XT1254 using Tapatalk
 
I just pulled all that emissions stuff off of a 351w f150 mid 80s. Replacing it for a edelbrock 1406 and dui hei dust. If you find out what you need , I can probably get it from the customer for you. Even got the carb, it's a 4brl holly made for ford.


Sent from my iPhone using Tapatalk
 
I'm not sure what carb it is. I can find out. It's an intermittent problem, though. It sounds fuel related to me. Cuts off while running down the highway. Sit on the shoulder for a few minutes and it will fire back up and run fine for a little while before doing it again. He says he can run it all day in town and it won't cut off, but yesterday's experience may have proven him wrong in that assessment. I'll try to get more information from him. Thanks.
 
I had a c-30 with a 350 that did that very same thing. Bad fuel pump. Could pump enough to get around town but would quit on highway. It will get worse
 
Both of the above suggestions are good. Also possible vapor lock. In town with little strain at low speeds it's ok. At highway speeds struggling to push a brick through the air it runs hotter and the shitty ethanol fuel vapor locks. A quick test would be to try ethanol free gas one tank. Also check for spark next time. I've seen coils break down with heat and quit sparking.

Sent from my XT1254 using Tapatalk
 
All three of those are things I've suggested, but I'm in no position to work on it, and he's more of an air-cooled VW guy. This engine baffles him. He needs a good local guy who can work on short notice. He's sure it's the carb, but as we all know, 80% of carb problems are fixed by an ignition tune-up. ;) It's amazing how competent mechanics turn into greenies when confronted with a carburetor these days.
 
Well, his mechanic finally threw up his hands and ordered a Holley. We'll see how this goes. Supposedly the pump and filter had been done and the emissions had been removed. He's been running 89 octane and some seafoam since I last talked to him and it had been running better, but it laid down on him Saturday and wouldn't clear up. Hopefully this rectified the situation. It sounds like trash somewhere to me, though.
 
catfishblues said:
Well, his mechanic finally threw up his hands and ordered a Holley. We'll see how this goes. Supposedly the pump and filter had been done and the emissions had been removed. He's been running 89 octane and some seafoam since I last talked to him and it had been running better, but it laid down on him Saturday and wouldn't clear up. Hopefully this rectified the situation. It sounds like trash somewhere to me, though.
Click to expand...
If it doesn't help tell him to try non ethanol gas. Ethanol starts to boil at 180*. I went round and round with my Fairlane, it would run fine til warm then it would start flooding and stalling, it would be a bitch to restart too. Let it sit 10-15 minutes though and it'd crank back up. I finally figured it out, the holley carb was a dual feed with the regulator on the fender and two 3ish foot braided lines running to the carb. The fuel under pressure would raise the boiling point but as soon as the needle would open and the pressure drops to atmospheric in the bowl it would flash boil. Gas would geyser out of that thing a foot high and it would drip out of the air cleaner.

I replumbed the fuel system like an injected car and added a return line. Now the gas doesn't sit in the line heat soaking no more stalling. Non ethanol gas fixed it without the replumbing, but all the stations nearby only have 87 ethanol free. This thing barely can run 93.

My car is running an electric pump at the cell so there's no vapor lock to worry about but with a stock mechanical pump the ethanol gas will boil in the line and vapor lock.

Sent from my XT1254 using Tapatalk
 
Last edited:
That's some cool tech, and makes a whole lot of sense......now if i could remember it if the situation arose....
 
WARRIORWELDING said:
That's some cool tech, and makes a whole lot of sense......now if i could remember it if the situation arose....
Click to expand...
I won't ever forget it I'll promise you! That thing whipped my ass for two months last spring and its only going to get worse as they increase the e rating. I found a mention of the flash boiling thing deep in a Google search at my wit's end on a chevelle site of all things. It all clicked into place then.

Sent from my XT1254 using Tapatalk
 
Duraspark ignition? Sounds like a classic case
 
Buying a carb might be the ticket.
In the mid 80s Ford liked to put POS 2 barrel carbs on the v8 (any size) to help with mileage mandates.
The carbs had plastic floats. Most junk yards had piles of the carbs ..... otherwise known as junk.
I would imagine ethanol would be the debil on one of these carbs!


Matt
 
catfishblues said:
All three of those are things I've suggested, but I'm in no position to work on it, and he's more of an air-cooled VW guy. This engine baffles him. He needs a good local guy who can work on short notice. He's sure it's the carb, but as we all know, 80% of carb problems are fixed by an ignition tune-up. ;) It's amazing how competent mechanics turn into greenies when confronted with a carburetor these days.
Click to expand...

ditzler motors downtown on the corner of 7th and liberty still works on the old stuff.
 
Lizooki said:
Buying a carb might be the ticket.
In the mid 80s Ford liked to put POS 2 barrel carbs on the v8 (any size) to help with mileage mandates.
The carbs had plastic floats. Most junk yards had piles of the carbs ..... otherwise known as junk.
I would imagine ethanol would be the debil on one of these carbs!


Matt
Click to expand...

bingo.

i fight carb issues on my 78 351m daily. its made it no fun to drive. gotta baby on the way so no money to upgrade the toy.
 
Ron said:
Duraspark ignition? Sounds like a classic case
Click to expand...

This^^^^

About 20 yrs ago I had an 85 FS Bronco with a 351 and factory Holley 4bll carb. That thing used to leave me stranded sometimes. I believe it was a bad ignition module mounted on the fender that caused the problem.
 
Back
Top