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moodydavid16

Re: Help with carburetor

#11

Home away from home

Update:
I have taken apart and cleaned my carburetor again.
The flooding issue turned out to be due to the float valve being damaged.
The original needle and seat had been replaced with a float valve that uses a rubber pad that pushes against a seat rather than a needle. This rubber pad had been badly damaged (I’m guessing it got pushed against its seat too hard by the guy who rebuilt the carburetor)
- picture 1
Because this had been damaged I chose to replace it with the needle and seat from my parts carburetor(I think it came off of a Hudson from a similar year) rather than reusing the original 2 piece needle and seat.
-picture 2
I also decided to replace the original fuel screen with the one from my parts carb as this one was much cleaner (it was slightly different in that the original one had its top folded in but the spare one has both ends open)
-picture 3
This ended up fixing the fuel leak problem, not sure about my other issue where the engine shuts off after just a few seconds of idling. It was getting too dark to see and I could not find my keys.

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Posted on: 2023/11/27 21:27

If you want something done right; you have to do it yourself

1948 Super Eight Touring Sedan

DavidPackard

Re: Help with carburetor

#12

Home away from home

Moodydavied16

The ‘flat disk’ valve is known as a ‘Daytona design’. The only downside of this design is the use of ‘extra’ seat gaskets to set the float level. While float level setting is covered in the Daytona directions, and millions of Zenith carburetors use ‘extra’ gaskets to set the float level, on occasion the tab on the float will not be set to touch the center of the Daytona valve. Excessive side force will result in a leaking valve, and engine flooding will likely follow. Since the valve is free of rotate the depression in the seat may appear to be the same all the way around, but that pesky side force may still be the culprit. IMO the flooding and idle problem are likely related.

In your second picture the valve in the lower right looks a lot like the accelerator pump check valve.

dp

Posted on: 2023/11/27 22:44

Dbedsole

Re: Help with carburetor

#13

Just can't stay away

Dirt/rust is likely source of your problem. Install a 10 micron filter on discharge of fuel pump. (Jegs)

Posted on: 2023/11/28 9:51

moodydavid16

Re: Help with carburetor

#14

Home away from home

Quote:

DavidPackard wrote:
Moodydavied16

The ‘flat disk’ valve is known as a ‘Daytona design’. The only downside of this design is the use of ‘extra’ seat gaskets to set the float level. While float level setting is covered in the Daytona directions, and millions of Zenith carburetors use ‘extra’ gaskets to set the float level, on occasion the tab on the float will not be set to touch the center of the Daytona valve. Excessive side force will result in a leaking valve, and engine flooding will likely follow. Since the valve is free of rotate the depression in the seat may appear to be the same all the way around, but that pesky side force may still be the culprit. IMO the flooding and idle problem are likely related.
dp

Ahh, yes that would make sense as the rebuild kit I got was from Daytona parts

Quote:

DavidPackard wrote:
In your second picture the valve in the lower right looks a lot like the accelerator pump check valve.
dp

That is entirely possible as I was not the one who took it apart and I just guessed/assumed it was a part of the needle and seat.

-Thanks for this information!

Posted on: 2023/11/28 11:32

If you want something done right; you have to do it yourself

1948 Super Eight Touring Sedan

moodydavid16

Re: Help with carburetor

#15

Home away from home

Quote:

Dbedsole wrote:
Dirt/rust is likely source of your problem. Install a 10 micron filter on discharge of fuel pump. (Jegs)

I realize this is a common cause of issues, however I respectfully disagree. I just don’t think dirt/rust is my problem. I’m not using the original fuel tank so I know for a fact that is clean. I also flushed the old lines out and plan on completely replacing them soon. I am also using a filter before and after the pump as well as a clear one right before the carburetor. Also when I took the carburetor apart and cleaned it again yesterday there was little(if any) dirt/rust inside.

Posted on: 2023/11/28 12:13

If you want something done right; you have to do it yourself

1948 Super Eight Touring Sedan

TxGoat

Re: Help with carburetor

#16

Home away from home

If the carburetor overflows or leaks internally, something is wrong. It takes very little foreign matter to cause carburetor trouble. Screens and filters help, but I have often found debris in carburetors that have both screens and filters in place. A new installation should have NO debris in the carburetor or filters or screens. Sometimes fuel leaks around the needle's seat where it it screwed into the air horn or bowl. That's worth a careful check even if it is tight. Once in a while, a new needle/seat will fail to seal properly. Even a very tiny defect can allow poor seating.

Posted on: 2023/11/28 12:26

moodydavid16

Re: Help with carburetor

#17

Home away from home

Quote:

TxGoat wrote:
If the carburetor overflows or leaks internally, something is wrong. It takes very little foreign matter to cause carburetor trouble. Screens and filters help, but I have often found debris in carburetors that have both screens and filters in place. A new installation should have NO debris in the carburetor or filters or screens. Sometimes fuel leaks around the needle's seat where it it screwed into the air horn or bowl. That's worth a careful check even if it is tight. Once in a while, a new needle/seat will fail to seal properly. Even a very tiny defect can allow poor seating.

Yes the problem of flooding in this case was due to the Daytona float valve being damaged.
If you look closely you can see the rubber pad is torn in the picture attached.

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Posted on: 2023/11/28 12:38

If you want something done right; you have to do it yourself

1948 Super Eight Touring Sedan

Fish'n Jim

Re: Help with carburetor

#18

Home away from home

If it's still stalling out, need to check if fuel or ignition problem. Check for spark as it dies. Timing light or spark tester.
See attachment on adjusting. Anti-percolation circuit on these.
I suspect it wasn't done right but can't tell over the internet. If they don't bench or engine test, and spec sheet can't tell if it's right when it comes back. A good shop will test.
'49 is WDG and I rebuilt myself and it would idle at 400 rpm for as long as I let it run - no heat-up, no stall out. Engine compartment wiring & ignition was fresh.

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46-48_Repair_Tuneup_Manual.pdf Size: 6,947.54 KB; Hits: 48

Posted on: 12/3 22:17

humanpotatohybrid

Re: Help with carburetor

#19

Home away from home

It takes a VERY large amount of pressure to damage one of those valves like that. Even if you just turn the air horn upside down, the weight of the floats on it will not even cause a visible indentation after immediate disassembly.

My guess is they were bending the floats in a very careless way. Probably with needle valves it would not have been a problem.

Posted on: 12/4 2:20

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