Float spring question

[JG1966]

Is the float spring supposed to apply pressure to the float up or down? I have a Holley 4150 DP with center hung float. I thought spring was supposed to apply some pressure up, to keep needle closed during bumps or turns, etc. Mine gives barely any tension but if anything it's definitely down not up. Thanks

 

[oldbee]

Should be up I think, but it's really not much tension in the scheme of things.

 

[gkent]

Tension isn't doing squat - think about it, when the carb is dry the float outweighs any spring tension, when the carb fills the boyancy easily overpowers the spring.

 

[steve340]

Many years ago I read what that spring is for but I cannot remember now.
The spring is not strong enough to hold the float up when dry if that is what you mean.
The float should "bounce" smoothly - no binding and all good.
Many carbs do not have the spring and the needle valves work OK.

 

[JG1966]

Tension isn't doing squat - think about it, when the carb is dry the float outweighs any spring tension, when the carb fills the boyancy easily overpowers the spring.

Thanks Stanton. The spring does seem pointless. It has virtually no tension. But Holley spent the extra pennies to put it in every 4150 so I figured it must do something.

 

[Xp29h]

I was teaching my daughter about float level today. She’s putting a carb on her 88 Ramcharger so I thought it might help her out. Anyway, I showed her on an empty 4150 dp off the car.. I found for demonstration purposes and understanding how it’s easier to see and feel how that spring works. Take the bowl off the main body, hold it upside down, loosen the lock screw and turn the adjusting nut either way and the float moves freely and easily..there isn’t a ton of tension. If you try it with the bowl right side up and dry, it doesn’t work well. Designed to be moved with fluid in it.

We went ahead and adjusted the floats in the charger tonight and she got to see the benefits of fine adjustments and how it all worked and how important it is to have the level just right.

 

[JG1966]

I was teaching my daughter about float level today. She’s putting a carb on her 88 Ramcharger so I thought it might help her out. Anyway, I showed her on an empty 4150 dp off the car.. I found for demonstration purposes and understanding how it’s easier to see and feel how that spring works. Take the bowl off the main body, hold it upside down, loosen the lock screw and turn the adjusting nut either way and the float moves freely and easily..there isn’t a ton of tension. If you try it with the bowl right side up and dry, it doesn’t work well. Designed to be moved with fluid in it.

We went ahead and adjusted the floats in the charger tonight and she got to see the benefits of fine adjustments and how it all worked and how important it is to have the level just right.

Your daughter has a good teacher. What I gather from this lesson is that the spring pressure supposed to be upwards.

 

[Xp29h]

Your daughter has a good teacher.

I don’t know about that.... I try! I’ve figured a few things out over the years but many more out there much better at it!! Thanks though!

Yes, it works the float upwards. That’s why it’s much easier when it’s full. The fuel lifts it up when you turn the screw. But, if the bowl is full and you need to lower the float, the fuel works against you. Like trying to push a ballon under water.. That said, it still isn’t all that tough to adjust and really not a lot of pressure to move it. Make sure engine warmed up and running as smooth as can. Just barely crack lock screw and turn adjustment. When I get close, it’s quarter turns at a time, lock it and check through sight window. Fuel should be just at or slightly below window without leaking out on own. A gentle rock of car side to side, a little trickle will appear. Lots of good Holley videos on the YouTube that show this and many other procedures.

If bowl is full, fuel will leak out a little when you crack open float adjustment screws (under pressure) so have rag handy to catch spills..

 

[JG1966]

I don’t know about that.... I try! I’ve figured a few things out over the years but many more out there much better at it!! Thanks though!

Yes, it works the float upwards. That’s why it’s much easier when it’s full. The fuel lifts it up when you turn the screw. But, if the bowl is full and you need to lower the float, the fuel works against you. Like trying to push a ballon under water.. That said, it still isn’t all that tough to adjust and really not a lot of pressure to move it. Make sure engine warmed up and running as smooth as can. Just barely crack lock screw and turn adjustment. When I get close, it’s quarter turns at a time, lock it and check through sight window. Fuel should be just at or slightly below window without leaking out on own. A gentle rock of car side to side, a little trickle will appear. Lots of good Holley videos on the YouTube that show this and many other procedures.

If bowl is full, fuel will leak out a little when you crack open float adjustment screws (under pressure) so have rag handy to catch spills..

Thanks Xp. Adjusting the float level isn't an issue. But I had the float bowls off and noticed the spring pressure was downward not up. That's what had me wondering

 

[RJRENTON]

Is the float spring supposed to apply pressure to the float up or down? I have a Holley 4150 DP with center hung float. I thought spring was supposed to apply some pressure up, to keep needle closed during bumps or turns, etc. Mine gives barely any tension but if anything it's definitely down not up. Thanks

IMO...
I believe the spring you are referring to is called the "bumper spring" and its purpose is to prevent minor fuel level functions due to fuel sloshing in the bowl. It fits under the floats fulcrum arm to help with the buoyancy.
BOB RENTON