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here is one of my other hobby's some work I just finished that I am quite proud of
http://www.flickr.com/photos/40736371@N00/?saved=1


its in a 78 F250 Custom, that is a 400 with edelbrock intake/carb and a hot cam with headers, its not fast but it will pull a house foundation out. just finished it yesterday and got 30 miles and a oil change on it today.

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If I had an antenna, I would; but I can only transmit on 160 meters.
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DE K7MHI

Clean setup you have a air filter for it I had one cough back and set fire what a mess.

That looks really good!

thanks guys, yea I have a older chrome one, its pitted some day if she is good I will get her the edelbrock chrome one so the top end is matching, but first its airbags and tires.

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If I had an antenna, I would; but I can only transmit on 160 meters.
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DE K7MHI

So you know your way around a 78 f250 custom with a 400 ??

I have a 78 F250 custom with a 400. It currently runs like shit and I really have no clue as to where to start.

Its hard to start unless you pour a bit of gas down its gullet and then you need to keep on the throttle to keep it going.

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Uniden BCT-8
Uniden BCT-7
Galaxy DX 959

It's hard to say where to start.
Pop the distributor cap off & inspect. Check plugs/wires.
Does it run better when warmed up? (choke)
Has it sat for for a length of time? (Gas gums up)

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Might want to check for vacuum leaks.

all the questions asked are good ones, how long has it ran this way? has it sat a long time?

you said it runs like shit... when you full throttle it will it run with out gas down the carb? will it idle at all when warm at any under 1000 RPM?

give some more history on the truck and problem

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If I had an antenna, I would; but I can only transmit on 160 meters.
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DE K7MHI

Yea it will run when i keep on the throttle after pouring gas down it to get it started.

unknown history on the beast I just picked it up a lil while back for 200 bucks. and have already made a couple of dump trips with it. once it warms up it still runs like crap but it will stay idling.

I picked up some new parts for it ( cap rotor plugs and wires) but as far as the carb goes Im totally lost on that.

I really dont see any vaccum lines in here but will do some more snooping.

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Uniden BCT-8
Uniden BCT-7
Galaxy DX 959

At a minimum one should go to the distributor. You should also have one to the PCV valve (unless its been removed) and one to the brake booster (if equipped with power brakes). All three of these are visible in spud's engine photo.

I don't know if Ford used evaporative charcoal canisters in 78. If so I'd expect one to go there too.

I had a 70 that blew the little cap off the 90 at the brake booster...

Boosters can leak internally also. So pull the line and plug it to test...

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

Only, and ONLY after doing all the previously mentioned work, one could investigate the functionality of the automatic choke... If all good there, then, I suspect, though, that the carb has accumulated some gunge...
and may need cleaning of internal air and fuel passageways... in particular the accelerator pump... This device squirts fuel into the carb when opening the throttle to prevent leaning of the fuel/air mix as it takes a bit of time for the vacuum to draw fuel through the main jets when accelerating from idle. Easy to see if this mechanism functions if you already have the aircleaner pulled to pour fuel directly into the carb, and the choke plate is "open".

Assuming there is fuel in the float bowl to begin with, one opens the throttle and looks for fuel being sprayed into the venturis of the carb... If not, with all else functioning normally, the engine will be very
difficult to start when cold as opening the throttle to set the automatic choke, if equipped with one that functions, will cause fuel to spray into the venturis of the carb and help "get things going"...
If this fuel isn't present, the engine then has to be cranked excessively in order to "suck" enough fuel through the idle jets to fire...

But, for a truck that moves under its own power for $200.00........

Eric
KB7DQH

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That is how the people at DARPA think. they take things and use them in unconventional ways, to see what happens.

Sounds to me like possibly more than one problem.
Typical in older, carboreted engines.

Hard start requiring fuel dump sounds like 1 of 2 problems (or maybe both)

I had same problem, float chamber was leaking down through valve in bottom.
Rebuild kit fixed that.

Also could be, as Eric mentions, Electric Choke, but as Eric says you want all your other ducks in a row before tackling that.

Poor idle does sound like a vacuum leak.

I would warm it, look for every vacuum hose coming off, and plug one by one.
Somewhere your idle should pick up.

Rebuild kits are cheap, and be sure to replace float while you are at it.

Directions included are usually pretty good.

once its warm I would just jam open the choke, the choke is the butterfly (flapper) that is very top of the carb you should be able to move it with the air cleaner off. try moving it to 100% open as far as it will go with out pressure or bending things (you never have to force a carb part)

if this isnt a issue the flapper is open and idle still stinks you might put some seafoam in the oil and the carb/gas it will smoke like a bastard but see if you can clean up the carb and valves the cheap way. not saying this will fix the problem but might help the dump truck run better

also MAKE SURE your vacuum advance is attached and you have no leaks there is a vacuum tree on the left rear of the engine (the break booster connects here) make sure there is no "tree" with out rubber connected to something good on the other end or a rubber cap

depending on carb, you have a EGR valve on the rear make sure this is connected to the EGR system or blocked off (its the center rear of the base of the carb)

then you will have 1,2,3 connections for PCV and vacuum on the front base of the carb the larger center one is PCV either block it or hook it up, then yo uhave 1/2 small vacuume hook ups connect one to the dizzy for the advance at idle, block the other or hook it up to something

advanced troubleshooting

I would check out a carb rebuild kit or timing issues mark the exact location of the distribuiter unbolt the dizzy and twist it clockwise just a bit (like 1 mm) see if it runs better (advance that engine) from there you want to make sure that you have no ping under load on the engine power break the truck and you should be able to tell that. It could also just be your curb idle screw that is off.

if your near east renton give a holla if you drive bye I would be happy to poke it with a stick and see if it will wake up.. Always like to save a old ford.

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If I had an antenna, I would; but I can only transmit on 160 meters.
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DE K7MHI

Thanks for the input. I'll get to it and let you all know how it turns out.

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Uniden BCT-8
Uniden BCT-7
Galaxy DX 959