Ford 94/ Holley 94 Power Valves

[fredeuce]

I recently rebuilt a pair of these carbs. One of the kits I used I purchased some years ago. On opening up the kit and on closer inspection of the power valve it appears to be unsuitable for this style of carb. It appears to be suited to the later Holley 4160 type 4 barrel carbs with the metering block.

I appreciate these carbs went through various changes over time however this doesn't seem right.

Any thoughts on this?

[chap52]

Check with "CharlieNY" on this site. He is the "94" guy for sure. PM him, I don't like to post other folks contact info without the OK. He has posted his email several times on here... Chap

[Charlie ny]

In photo on the left the power valve on the left is at home in a modern Holley...horizontal position. The
spring retainer will most likely contact the relief inside the bowl AND the 2 'window' openings
will make air and liquid sealing challenging at best. The PV on the right is more correct
but it too has square 'windows' for fuel passage but usually works . In the rh photo
the PV on the right is genuine Holley from way back. It's design and manufacture is superior to the newbys . Escape path for fuel is provided by 3 small orifices on the shank and the die casting is head and shoulders above the others. The diaphragm material however won't take alky. The only consistantly acceptable PV's are those sold by DAYTONA PARTS 386 427 7108 ask for Jennifer. IMHO

As usual that's the long answer.
Charlie ny

[51504bat]

Originally Posted by Charlie ny

In photo on the left the power valve on the left is at home in a modern Holley...horizontal position. The
spring retainer will most likely contact the relief inside the bowl AND the 2 'window' openings
will make air and liquid sealing challenging at best. The PV on the right is more correct
but it too has square 'windows' for fuel passage but usually works . In the rh photo
the PV on the right is genuine Holley from way back. It's design and manufacture is superior to the newbys . Escape path for fuel is provided by 3 small orifices on the shank and the die casting is head and shoulders above the others. The diaphragm material however won't take alky. The only consistantly acceptable PV's are those sold by DAYTONA PARTS 386 427 7108 ask for Jennifer. IMHO

As usual that's the long answer.
Charlie ny

Long or not, it's the right answer as always.

[dakotafarmboy]

Ok. I put a vintage speed kit into a Ford 94 last summer. Including a new power valve.

The motor seems to be running so rich that it floods itself out at idle…if that’s even possible.

After adjusting the air screws a little, I started thinking it was a float adjustment thing…and that may have something to do with it.

Anyway, I came back to the Barn for some advice and came across a couple of Tubman’s posts on filling the bowl to see if the level drops appreciably. I thought that was a good place to start.

I filled the bowl and covered it with tin foil. 48 hours later it had gone down at least 3/4 of an inch.

I assume it is not supposed to drop that fast??

My plan is to call Daytona Parts and have them send me a new power valve. This time I will do the bowl test before I install the carburetor.

My question is this…is any drop in the fuel level level acceptable? Or should it stay put at the level where I filled it…but for a little evaporation?

[ford38v8]

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A clean napkin on the table will show if it leaks. Either the diaphragm is broken or the body did not seal. Inspect the mating surface for a proper flush (flat) machining. The gasket may also have been compromised, or it wasn't fully tightened. You can test the diaphragm with suction against your tongue.

[Tinker]

Isn't the new power valves for 94s not seat? Charlie will know. Remember a few yrs back, they are oversized and you need clear some internal space with a dremal.



If the bowl is leaking after a day, something isn't right.

[Charlie ny]

Scroll back into Mart's marvelous shop video's...the one I'm referencing is rebuilding
a 94 style carb. You will observe the steps required to get a 94 bowl ready to build into
a proper carb. The bowl is fixed in his milling machine and the bottom face milled flat.
Is this step always required, probably not, you may get lucky. Consistently Daytona
Parts has the best gaskets and components.


Fuel evaporation in the bowl overnight down 1/2 way is expected. Ford38v8 x2
Charlie ny

[1948F-1Pickup]

I need to get a better/more consistent fixture for testing power valves. That fitting Mityvac provides with their pump isn't foolproof.
After (sometimes significant) screwing around with that horrible fitting, a lot of the power valves (brand new) that I've checked do show internal leaks that would effect proper operation under vacuum.

[ford38v8]

Originally Posted by 1948F-1Pickup

I need to get a better/more consistent fixture for testing power valves. That fitting Mityvac provides with their pump isn't foolproof.
After (sometimes significant) screwing around with that horrible fitting, a lot of the power valves (brand new) that I've checked do show internal leaks that would effect proper operation under vacuum.

A foolproof testing method is your tongue. Suck on the valve, and if it holds a suction to your tongue it’s good.

[dakotafarmboy]

Okay. Thanks, fellas. Very helpful.

I ordered a new power valve (actually another kit) from Daytona Parts this morning.

That will give me time to go back and find Mart's video on rebuilding a 94 carb.

[Bored&Stroked]

There are multiple issues to think about (to add to what others said):

1) The fuel ports and gasket sealing area on the newer style power-valves are not correct for the 94's - and will frequently leak. Sometimes you can "fix" this area on a lathe.

2) On old/vintage power-valves, I've seen the diaphragms harden up - so while they may or may not leak, they no longer are the same flexibility as they should be . . . causing them to not function properly or not at all.

I'd get new power valves and gaskets from Charlie or Daytona . . . and test your carb bodies to make sure they are not leaking when you install them.

[dgsmith]

To CharlieNY (can't send PMs yet)

Hi, you seem to be the man everyone refers to. If I can steal a little of your time .

I am assembling a 4 carb. (Holley 94) setup on a mildly built, low compression, Olds 303. I am looking for occasional cruising, not top power. I currently have three usable 94s (two "2100" and one "Ford"). They are in very good condition, possibly N.O.S. I plan on using straight linkage, not progressive.

I assume they have to be internally identical (Power valves, jets, squirter). For my needs what would you suggest for power valve rating and jet size?