Technical Car using a lot of gas

No one suggested another likely culprit, the power valve is probably leaking because its blown or not sealing because it's the wrong style. It will just dump as much fuel as you can feed the carb.

 

When cars set, ***uming Yours has, First things you wanna replace are fuel pump, Master cylinder, First...
Then wheel cylinders, Possibly tire's etc like mentioned above... Shoot a couple pictures an load them up.. sometimes a simple picture of what you have going on can help from a far..

 

Charles,
You can do a simple test to see how much gas you are losing through the power valve.
Bucket Test...
All you need is a bucket that the carburetor will fit in. A lid for the bucket and a little block of wood the the carburetor can sit on.
Remove the carburetor from the car. Remove the air horn or top of the carburetor. Fill the fuel bowls, not full to the top but like they would be with the floats in. Place the carb on the block of wood. Put the lid on and let it sit 2-3 days.
If there is gasoline all over the block of wood in in the bottom of the bucket, then you know the carburetor is leaking into the engine....

This is good advice and I'll add my 2 cents as a Shoebox owner...
It is possible for gasoline to get into the engine through the fuel pump. In my opinion it's not as critical as it is with some engines due to the fuel pump being on a stand. The reformulated gasoline can be hard on the rubber parts. In my opinion if the fuel pump is pumping, you should be OK. Always keep a close check on the oil when you are getting a engine to run. If the level rises at all...at all, on the stick... You know gas is coming from somewhere.
It's always a good idea to have a spare fuel pump especially these days with the ****py gas we have.

This may be getting ahead, but here goes...

Brake Master Cylinder...
If you have brake pedal this means the master is working. If you have "pedal", this is a good sign.
If you have "pedal" this means that master can most likely be inspected serviced and over hauled....On the car! Replacing the master cylinder on a 1949-51 Shoebox Ford is a big deal.

If you have good pedal, I would try servicing it first. I'll get to what I did with my master cylinder in a moment....

Brake Lines and Hoses...
I have a rule...If a brake nut (fitting) cannot come off the whole entire line needs to be replaced. If it's rusted enough to stick the nut and not turn. It's rusted enough for the brake line to fail. Of course, I try my best to spray the fittings with penetrating oil and use good fitting (line) wrenches...
https://www.inlinetube.com/collections/all/?year=1950&make=ford&model=custom

Unless they are new or fairly new, it's a good idea to replace the three rubber brake hoses. If "black" comes off on your hands, this means they have deteriorated enough to be replaced.

Brake Wheel cylinders....
The wheel cylinders are out board and thus are the most exposed. Also, they are at the end of this hydraulic system thus are more likely to be damaged by water and corrosion that gets into the system.
The wheel cylinders will lock up and fail first. My '51 Coupe sat in storage for who knows...? It had a good pedal but only one wheel cylinder was fully functional, the right front. One of the rears was barely working. I had planned to rebuild them all but only the right front was rebuildable.

Even if the car has brakes, it's a good idea to take the brakes down, remove the shoes and springs...Check the backing plates for grooves on the pads that the shoes slide on. I these are grooved, they can hold the shoe (grooved backing plates can cause all kinds of problems from stuck brakes to no brakes)....Most of the time you can grind with a dremel and finish with sandpaper if the backing plate has minor wear.
If the wear is severe, you may have to have the grooves welded up and smoothed rather than simply smoothing them....
Once you have the hardware and shoes off (it's always a good idea to one side at a time, that way you can look at the other side to make sure you are putting it back together correctly), take the rubber caps and pins off the wheel cylinder. If you are doing one wheel and had a good pedal, get into the car and press the brake. This will pop one side (piston) out of the cylinder.

You should be able to tap the other side out with a drift. If that piston is locked tight and does not drive out with reasonable force...Replace the cylinder. If the bore is severely pitted, replace the cylinder. There will be a lot of goop and mud like stuff in the wheel cylinder. Clean all that out. You can hone your cylinder with a hone but that's just to smooth it, not re-bore it...

It's a good idea dis***emble and clean the brake wheel cylinders out every couple of years. It's a good idea to do the master too. The rebuild kits are to renew good working cylinders with new rubber and springs. They are not meant to rebuild corroded, pitted and stuck cylinders. If they are that bad...they need to be replaced.

Also the backing plated need to be greased with "brake grease" where the shoes slide. This is never done and is one reason why the backing plates are damaged.

Inspecting the master brake cylinder...
The Master can be dis***embled from under the car. You take the pedal ***embly off the cylinder, pop the boot and pin/rod off, remove the retaining ring and the guts will come out. While the master guts are out you can inspect the piston for wear...inspect all the rubber for wear...inspect the springs for damage and corrosion, replace with a kit if necessary. If the cylinder will not come apart (piston locked up) when the retaining ring is removed or the bore is severely pitted, it needs to be replaced. Expect there to be goop and mud in there like the wheel cylinder.
To replace the master means removing a panel from the driver inner fender (one bolt is inside on the floor) and dissembling the clutch and brake pedals. It's a big job.

Since I had Pedal, I dis***embled my master under the car and replaced the parts with a overhaul/rebuild kit. It does wonderful. Of course, you will have to bleed the brakes, maybe several times.

Brake fluid draws and mixes with water so this is why you need to "clean out the system" every few years. Too, by doing this you inspect the shoes...front wheel bearings...drums...emergency brake function...rear axle seals...and grease the backing plates.
Doing the brakes on these is a nasty labor intensive job, this is why brake systems can be in such poor condition.

When the brakes are inspected/cleaned/renewed, they will need to be properly bled and adjusted.

Parking/Emergency brake...
With a single pot master...The emergency brake has to be in good working order. In general use, a must for a manual shift car. really, it needs to be functioning on any car but it is critical on an old car like a Shoebox.

Tires...If it has radials that are close to 10 years old, they need to be replaced. Bias tires you can go longer but radials have a shorter "shelf life".

10 year old radials no matter how good they look are yard tires.

Before all this, figure out what's going on with the fuel system. With that said...this needs to be done before the car is road ready....

 

My last 8ba, when the condenser failed, it acted like carb issues... Washed the rings and all...

Another issue that could be possible is the fuel pump leaking past the diaphragm. And as others said the power valve blown can cause issues. But your consumption issue is deff one of these 3...

You know its going into the oil so its going through intake or down the fuel pump into the crankcase.

 

I knew I forgot something... The Three hose's(brake's) Most overlooked task..

 

i know one thing . letting a car sit and warm up .playing with timing /carb adj. ,etc for a while uses a lot more fuel than i expect . a gllon seems to go pretty fast . i think thats why my prius shuts off at traffic lights . it adds up quicker than you think .

 

I'm going with the fuel pump diaphragm has a leak from ethanol gas eating through it.

 

Thank you for this info. I was sure I had a fuel problem with the 289 in my '40 Coupe. Put new carb on after checking fuel lines and filter. Same problem, then I read your post this morning. I had replaced distributor with new one (still points) when I bought car back in April. Ran good until 2 months ago. So, after seeing your post, I put original distributor back in and everything is good. In all my years as a mechanic, I had never run into this problem. It pays to read the HAMB. Thanks again. Ron

 

here's what you do:

get it running.
be sure the speedo and odometer is working.
fill the tank up all the way.
write down the mileage
drive 50 miles or so.
fill it up again.
do the math and tell us what your gas mileage is.

anything else is just ******* in the wind.

 

OP has stated he has fuel in the crankcase.
I’d be working on that issue and not focusing elsewhere.

 

Like changing the oil.

 

OP, these guys are steering you in the right direction, but offering many things to check.
I will group them in an order that makes sense to me. You can check in your own way, but check them all.
Change the oil. It is currently a danger to the life of the engine. Fuel does not support bearing loads.
Check the fuel pump diaphragm. This will allow the most fuel into the engine and wipe out your oil change the fastest. Replace or rebuild if needed before moving on.
Fix the carb. You mention it's leaking after cleaning. Leaks are a fire hazard and not something a good carb will do. It's a known issue, fix it.
Do a complete tuneup. Check compresion, set up the distributor properly and replace the plugs. Follow the proper procedures for a complete tuneup. Check voltage, ignition parts, advance and spark output.
Once this is all done, report back with the results.
Just doing some of this will mean you still don't know if everything is in proper working order.

 

Glad I was able to hit the mark on it for ya... Yeah you dont expect it since it still runs and fires... Get to enjoying it man...