1957 Ford Thunderbird - Carburetor Issue - Dumps fuel when shut off

My 1957 Thunderbird has the 312 motor with a Holley 4 Barrel carburetor has developed an issue with the carburetor.

When I shut it off, fuel continues to drip into both barrels, causing the car to flood. This does not happen every time I shut it off which leads me to think that there is some foreign material in the bowls?

Another issue which I was able to stop was this; (maybe related maybe not)

The throttle stop screw on the drivers side of the card was turned in so far it was forcing the rod that attaches to the plunger on the top of the front bowl to leak fuel at an idle. I was able to adjust this screw, which did rise the idle a little to stop this leak.

The number stamped on the carb are:

dcpf-9510u

list -4548

2667

I am not sure if this is the correct carb or not? If not, is there a better option for a new replacement?

thank you for any help you can offer.

Jon

The correct carburetor should be a Holley 4160 or an Autolite 4100.

Your carburetor looks like a 4160 but the numbers you gave come up for a late 60's early to 70's applications. The jetting could be wrong for your 312.

You might try posting a question at Y-Blocksforever Forums

That's were all the Ford Y block discussions get the most action.

Try this link:

THE CARBURETOR SHOP / Troubleshooting

Jon.

Jon, The original carburetor that your '57 came with was a Holley 4150 and had a Ford ID on the air horn of "ECZ AD" or similar Ford engineering code letters. These letters would designate, what Ford cars they

were supposed to be on. The List #, also on the air horn was "LIST 1273-1; 1A or similar. Your carb is a 4160 that has adjustable float levels and has no secondary fuel metering block. The 4150 did not have adjustable floats, but it did have a secondary fuel metering block. This 4548 you have is a generic FORD replacement model that adapts to many later Fords and your T-Bird. The correct, new, replacement car ... linkage and CFM wise would be a Holley 0-1848-1. Summit Racing carries them at a reasonable price.

If its dripping fuel into the front two barrels, your power valve that's located in the primary (front) fuel metering block is shot. It's ruptured rubber diaphragm is letting the front fuel bowl empty into the intake manifold, causing the flooding. Shrunken secondary gaskets can also leak fuel into the secondary throat and into the manifold.

The Autolite 4100, which was a FORD designed carburetor, was never used on a '57 T-Bird, but first appeared on Fords in 1958 or 1959. However, it will adapt to most '57 and later Ford style intake manifolds.

Bob Hartig

McLean, VA

'57E, '57D

Jon, The original carburetor that your '57 came with was a Holley 4150 and had a Ford ID on the air horn of "ECZ AD" or similar Ford engineering code letters. These letters would designate, what Ford cars they

were supposed to be on. The List #, also on the air horn was "LIST 1273-1; 1A or similar. Your carb is a 4160 that has adjustable float levels and has no secondary fuel metering block. The 4150 did not have adjustable floats, but it did have a secondary fuel metering block. This 4548 you have is a generic FORD replacement model that adapts to many later Fords and your T-Bird. The correct, new, replacement car ... linkage and CFM wise would be a Holley 0-1848-1. Summit Racing carries them at a reasonable price.

If its dripping fuel into the front two barrels, your power valve that's located in the primary (front) fuel metering block is shot. It's ruptured rubber diaphragm is letting the front fuel bowl empty into the intake manifold, causing the flooding. Shrunken secondary gaskets can also leak fuel into the secondary throat and into the manifold.

The Autolite 4100, which was a FORD designed carburetor, was never used on a '57 T-Bird, but first appeared on Fords in 1958 or 1959. However, it will adapt to most '57 and later Ford style intake manifolds.

Bob Hartig

McLean, VA

'57E, '57D

You are correct the Autolite wasn't available on T-Birds in '57 but they were available on 312's with A/T in '57. I actually have one.

Since Jon has a '57 T-Bird, I was trying to focus on what carburetors were available for his particular car, and, yes, in 1957 Ford offered quite an array of carburetors for the Y Block passenger

models. I had an all original, low mileage '57 Ford Skyliner that came with a Carter 4 barrel ... was also used on the '57 Continental MK II. I think Ford gave up on the Carter's after '57. I've had

at least four '56 Fords, the last of which was a Parklane wagon with O/D ... 1956 was a Great Year!

Bob Hartig

Since Jon has a '57 T-Bird, I was trying to focus on what carburetors were available for his particular car, and, yes, in 1957 Ford offered quite an array of carburetors for the Y Block passenger

models. I had an all original, low mileage '57 Ford Skyliner that came with a Carter 4 barrel ... was also used on the '57 Continental MK II. I think Ford gave up on the Carter's after '57. I've had

at least four '56 Fords, the last of which was a Parklane wagon with O/D ... 1956 was a Great Year!

Bob Hartig

Actually, it was more like Carter gave up on the design which Ford wanted to use......the unreliable secondary diaphragm!

Carter made them for Ford (and a few Chrysler) for a couple of years, instead of the bulletproof airvalve design used for others. The secondary diaphragms were trouble, period, and Carter refused to continue making them.

Ford (Lincoln) used Carter though most of the 1960's until the spread-bore carburetor became popular. While Carter had a racing only spread-bore in 1969, Carter did not release spread-bores for production until 1971.

Ford did use the thermoquad on many of their high performance non-smog engines in the mid 1970's and newer.

Jon.

Try this link:

THE CARBURETOR SHOP / Troubleshooting

Jon.

Good article. From what I read, high fuel levels or high float setting or needle and seat leaking cause this after shutdown, especially heat soaking. I have seen a phenomenon like "wicking" also, contaminants build up a layer on the surfaces. You should try a new needle and seat and recheck float for leaking and filling with liquid and reset float level. You might even add a small 0-15 psi guage at carb inlet to monitor pressures,. If there is a fuel level plug on the side of that Holley, remove it after shutdown and see it fuel keeps running out. John

Siphoning: Does that model have the tiny check ball underneath the accelerator pump and sqirter nozzle, one may be beneath the nozzle retainer screw in the body, could it be missing?

I see help has arrived, Jump in here CarbKing!....

Jon (like your name spelling ). As noted above, the original carb for your T-Bird would have been a Holley list number 1272 for a standard trans, or a Holley list number 1273 for an automatic trans.

If you are not hung up on originality (your query asking for modern replacement), then (as noted by others) both Carter and Autolite were used by Ford in 1957 on the passenger cars (other than T-Bird).

Others will have differing opinions, but mine is that both the Carters and the Autolites for 1957 have issues; although fewer than the 1957 Holley. The Carter's major issue (I posted this earlier) is the unreliable secondary diaphragm. The Autolite also has a secondary diaphragm. Also, the Autolite was totally redesigned for 1958. About the only pieces interchangeable on the Autolite from 1957 to 1958 are the body screws. Parts for 1957 Autolites are available, but constructed from "verypricium"!

My suggestion for a different carb would be a rebuilt (I doubt few new old stock exist) Autolite from a 1958 or newer THAT WAS ORIGINALLY USED ON A 312. Virtually all parts (excepting the secondary diaphragm) are readily available and inexpensive. The secondary diaphragm is also available, but not inexpensive.

I do not know what changing to the 1958 or newer would do as far as distributor requirements. Not certain when Ford got rid of the loadmatic distributor. Going to take a Ford electrical guru to answer that possible issue.

Jon

Thank you for all your advise.

Carbking, Thanks for the Carter info. A friend of mine has a '60 Corvette with dual 4 barrel Carters and after he installed new, fresh carburetor tune up kits to both, he discovered that the accelerator pump cups were binding in their bores to the point that the lips of the cups were flipping up. This occurred shortly after ran the engine. He indicated the bores were clean and smooth, yet this was happening. Any thoughts on this? Were the original cups rubber or leather and what do you think is the type material of the cups in the new kits? Thanks again, Bob Hartig

Jon, Last year of the Ford "loadamatic" was 1956. In 1957 the distributor had a ball bearing breaker plate; centrifugal advance as well as an adjustable vacuum advance when matched with the Holley 4150. The '55 & '56 T-Birds with loadamatics don't perform very well with the Holley 4150/4160 because of the vacuum only distributors and carburetor spark valves. Bob

Bob - original pumps were leather. Due to cost, the new cheaper kits are made from rubber which is at best questionable in modern fuel. The better kits still use leather. Quite common for the rubber pumps to act as you indicate.

One other possible issue: since (except for Carter) rubber (neopreme) has been the norm for probably 40 years, many are unaware that leather cups should be oiled with a light machine oil prior to installation. Failure to oil should not cause the issue you mention, but may result in the pump acquiring wear if the operator works the throttle several zillion times prior to installation on the car.

Jon.

Since Jon has a '57 T-Bird, I was trying to focus on what carburetors were available for his particular car, and, yes, in 1957 Ford offered quite an array of carburetors for the Y Block passenger

models. I had an all original, low mileage '57 Ford Skyliner that came with a Carter 4 barrel ... was also used on the '57 Continental MK II. I think Ford gave up on the Carter's after '57. I've had

at least four '56 Fords, the last of which was a Parklane wagon with O/D ... 1956 was a Great Year!

Bob Hartig

The carter carb on the 368 Y block for the '57 Continental Mark II was a WCFB. This set up was also used on the Merc Turnpike Cruiser. Even with the vacuum secondary setup the unit was still a vast improvement over the 56 Holley 4000 "teapot" by most owners of the cars. The hard thing to find is not the carb it is the Tach Drive Dizzy as the 56 models came with the all vacuum advance "Load-O-Matic".

When I got my first Holley Variable Spec Manual (circa 1972), I was amazed that the Holley 1850 was a "one size fits all" Ford V-8 carb. The applications it was spec'd for went from the 312s to 430 V-8s. I didn't comprehend how one set of jetting specs could cover all of those models and model years!

In later years, the Holley 1850 has been "bastardized" and became the Holley 4bbl "price leader" in the speed shops. Manual choke, "generic" jetting, etc. Want an automatic electric choke? That's extra. Need to re-jet? That's extra, too (time AND labor). End result is that the Holley 1850 which is NOW available (since the middle 1980s or so) might NOT work very well on the earlier Ford applications . . . "as sold" now. To do so, you'd need to find the old jetting and metering block/plate specs and replicate them into the newer carb for best results. Adding the electric choke can be doable, too.

I'm wondering how well one of the 500 cfm Edelbrock/Carter AFBs might be as a '57+ Ford Holley replacement? The Ford 4100 carb might be an option, as would the later "same style" Holley 4bbls of the 1980s, but the Ford carbs just looked a little less sophisticated in the venturi and design department compared to the AFBs adn certainly the Holley 4bbls of that time (4150 or 4160). Of course, if you've got to have "correct" for show/judging activities, that's what you need . . . at any reasonable cost.

Just some thoughts,

NTX5467

I was able to find a few tach-drive distributors without even looking for them when I was looking for a dual diaphragm vacuum advance last October on eBay.

I think any cab is a vast improvement over the teapot or AKA the towering inferno. I actually learned first hand why they call it that. I had mine catch fire after I had trouble restarting it. Luckily, I was able to get it put out before it caused any damage.

I currently have all the parts needed, including a '57 B manifold, to covert my '56 292 to an Autolite 4100 so I won't need to worry about another carburetor fire.

hey Where is that plastic 7/16" carb spacer  to keep heat down .  ?   this will go along way even with the coleman lantern fuel we use as gasoline ,