Fuel issue (I believe)

[1969Falcon]

Hello all,

My first post after two years of lurking. Unfortunately, I come to the forum with a question about some car trouble.

Yesterday, I was driving my 69 Falcon with a stock 200 six and C4 transmission and it started bucking and stuttering. The problem got progressively worse, although I was able to limp home. I determined it is a fuel issue. All my ignition components are good and hooked up correctly, the battery is charging and holding the charge just fine.

Yesterday afternoon I replaced the fuel filter, and swapped a different fuel pump in. Didn't make a lick of difference. I tapped on the carburetor to see if the float was stuck, and nothin' doin--although it did seem to make a very shortlived difference. There isn't anything obstructing the fuel line to my knowledge.

I noticed the problem occurred when I would roll just onto the throttle, and subside a little as the revs went up. Starting it today, the engine hardly runs at all, even at idle.

FWIW, the engine has what I believe to be the original carburetor, though the engine itself was rebuilt a few thousand miles ago. Car was running fine until yesterday.

Any thoughts?
Thanks

Here's some pictures for your troubles:

 

[Explorer]

Noticeing a difference, however short lived, by tapping on carb would be enough for me to tear it down.

 

[bubba22349]

You could try doing a fuel volume test. Once in a while the fuel tank pickups (sock) can clog up or if there is rust or other trash in a tank can plug up the end of fuel pickup too If you have an air compressor you could try blowing the fuel line back to the tank. If you find that you have the fuel volume after that X2 and it's probably time for a carb rebuild. That's a nice clean looking Falcon.

 

[1969Falcon]

Thanks for the replies, everyone.

I did try using some compressed air to clear the fuel line back to the tank yesterday, which didn't change anything.

I guess I'll look into taking this carburetor apart!

 

[chad]

Sorry, keep in touch after, to let us know
AND
Yes, I love pic! ESP. of such a nice one!
(love those steelies 2, h.caps R the last detail for a 100% beauty @ ur house. even liked the w.shield washer 'tank').

 

[1969Falcon]

I appreciate the comments, guys!

Unfortunately, the paint isn't QUITE as good as the picture makes it out to be. I have a bunch coming off on the roof. The car is, however, basically rust free.

 

[ludwig]

If you do repair the carb, do it over a large flat surface and cover it with a single color paper rather than newsprint. That way if you drop a spring or ball or something it is easier to find. And if you soak or rinse something, do it in a non-metallic bowl. Now if you already know all this, sorry. If you don't, I hope it helps. It's not a hard job with these carbs.

 

[chad]

has what I believe to be the original carburetor

What model is that?

 

[schaferstephen]

Dude, I had a problem almost exactly like that with mine. Got to the point where it would barely even IDLE! I rebuilt the carb (a Holley 1940) but I ended up putting an autolite 1100 on it. Solved my problems, runs better than ever now. Guess what I'm saying is, start with the carb. Good luck man!!

 

[1969Falcon]

The carburetor I have is marked "Motorcraft," I don't think it is an Autolite. I assume "Motorcraft" was marked on carburetors of numerous makes which were installed on Ford vehicles or offered as replacements?

Upon inspection, I believe it is the Holley 1940.

Is it worth replacing the carb? (I've had issues before, float sticking, etc.)

 

[MPGmustang]

It sounds like the carb to me also, but don't over look other simple things, like oil level or trans fluid level. it could be simple spark vacuum can or a vacuum leak. just take a quick glance at all cause I know low levels of fluids can cause random symptoms too. even old points... a bad coil,

but as mentioned, you noticed a difference when you 'tapped' the carb... that's a good guess that it could be related.

 

[chad]

"...is it worth replacing the carb?..."

I usually ask a diff. 1
"Is it worth rebuilding?"
Considering myself less than a shade tree mechanic I did not ask that Q B 4. Folks on here helped me rebuild one tho! This is why I asked U the Q "whatja got there?" Let C what the ex-spirts on here have to say (I'd rebuild it, if it is the cause, cuz I'm cheep [read unemployed off the acreage]) about the worth of the carb itself. U compare that w/what you wanna do/can afford.

I believe it is the Holley 1940
what tells U that? Compaired it to a pic/sketch, run down the correct numbers on it? Whaddaya say guys, is that a goodun?

 

[1969Falcon]

I'm away from the car and will be for a week, I'll get some more info off the carburetor next weekend. I'll also check all my fluids! I DID check to make sure all vacuum lines were connected properly. Points and coil and all other ignition parts are good as well.

I experienced the effects of a bad coil a couple summers ago, heh.

I thought it was a 1940 based off of images on the internet.

Thanks guys!

 

[chad]

1940 based off of images on the internet
so it must be then, talk 2 ya in a wk (don;t forget to get back 2 us, my curiosity is up now you, you, you....& I got a soft spot in my heart for the rig now U introduced me w/that pic)
8^0
BTW: (not guaranteeing this is the problem) isn't there 2 fuel filters? Put 1 (not the 1 stickin outta the carb) w/the see thru body on so U can C what she sucks up. There's a costing U can put in the tank, once out & able to slosh it around good, that can stop crud from commin outta the tank. Some just replace the tank instead.

 

[nachoman]

Did you look at your spark plugs to see if one is fouled? I've also had a similar problem due to a frayed condenser wire that was grounding to the distributor casing.

For a fuel problem, take the air cleaner off, run the engine at fast idle, and look down the carburetor. Look for gasoline dripping from the venturi at idle (be careful not to confuse this with accelerator pump spray - which you won't see if the engine is at a constant throttle setting). If you see liquid gasoline, you have a carb problem.

 

[rbohm]

8) another thing nearly everyone forgets to check is the rubber fuel line from the tank to the steel line that goes to the front of the car. a friend of mine and i replaced that line on an olds we were working on, and suddenly we had plenty of fuel being drawn from the tank.

 

[1969Falcon]

Hi all,

I appreciate the replies but unfortunately I am away from the car again (at college). I will post my progress once I get back into getting the thing running again early/mid May. I will check that rubber line and inspect the fuel flow in the carburetor at idle.

...I really need to get this thing going once I get back home--it's my summer daily driver

 

[1969Falcon]

For a much belated update:

Turns out the problem wasn't fuel-related at all.

The points had come out of adjustment from the adj. screw going loose--they were closed up. Before fixing this issue, the car started really backfiring when you tried to drive it and the backfire led to another problem--the muffler got pretty bunged up.

With the points properly adjusted and the exhaust fixed, the car runs like a top.

 

[Asa]

Glad you got it fixed up
However, the fact that tapping on the carb helped still would give me a reason to wonder. If I were in your place, and I had the time and know-how, I'd likely pull the carb apart, make sure there's no trash in it, and ensure that everything is working properly.

But I can also fully understand not messing with something that's running well

Enjoy!

 

[bubba22349]

Excelant glad you got it figured out