Zenith WIP Float Setting

[rixter]

Hello,

Is there a "dry" float setting for Zenith WIP carbs? All I am finding are fuel level settings that measure the fuel level down from the top edge of the carb with the cap removed and of course this would be with fuel in the carb. At the end of the day, this "wet" method may be more accurate, but I wanted to get an initial setting with the carbs on the bench after rebuilding.

The Strombergs and other carbs with a float with a tab that presses on the needle valve/seating combination have setting methods where you flip the carb over and take a measurement between the float and the carb base while dry. On the WIP the needle valve is attached to the float tab and the needle valve seating is screwed into the carb inlet port. I suppose you could pull up on the float until the needle seated and take some measurement... I just have not found what that is.

If a wet setting is the only option, I'd like to know more how best to perform this. Can it be as simple as adding some fuel to the bowl with the top cap removed and when the float rises enough to keep the fuel from running out the inlet port I measure the height of the fuel level from the top edge? Or do I have to simulate a more real world scenario where I am rigging up something to introduce the fuel via the inlet port under some pressure and see when the float stops rising? Seems like a mess.

What concerns me is that the carb kits that I obtained contain a needle valve that is a bit shorter than the needles removed. If I am to replace these, and I am not convinced I have to from the condition of the existing ones, this would either require adding washers under the brass valve seat or bending the tab on the float. I'd rather do this playing around dry.

Thanks
Rick

 

[RootesRacer]

Hello,

Is there a "dry" float setting for Zenith WIP carbs? All I am finding are fuel level settings that measure the fuel level down from the top edge of the carb with the cap removed and of course this would be with fuel in the carb. At the end of the day, this "wet" method may be more accurate, but I wanted to get an initial setting with the carbs on the bench after rebuilding.

The Strombergs and other carbs with a float with a tab that presses on the needle valve/seating combination have setting methods where you flip the carb over and take a measurement between the float and the carb base while dry. On the WIP the needle valve is attached to the float tab and the needle valve seating is screwed into the carb inlet port. I suppose you could pull up on the float until the needle seated and take some measurement... I just have not found what that is.

If a wet setting is the only option, I'd like to know more how best to perform this. Can it be as simple as adding some fuel to the bowl with the top cap removed and when the float rises enough to keep the fuel from running out the inlet port I measure the height of the fuel level from the top edge? Or do I have to simulate a more real world scenario where I am rigging up something to introduce the fuel via the inlet port under some pressure and see when the float stops rising? Seems like a mess.

What concerns me is that the carb kits that I obtained contain a needle valve that is a bit shorter than the needles removed. If I am to replace these, and I am not convinced I have to from the condition of the existing ones, this would either require adding washers under the brass valve seat or bending the tab on the float. I'd rather do this playing around dry.

Thanks
Rick

I dont recall ever having trouble setting the float height on zenths but then I again its probably been 25 years since I switched over to stroms briefly and then to DCOEs.

What I would do is measure the current float height with the old needle and seat (with the top case vertical so as to not compress the needle and seat), then replicate this measurement on the new parts on both carbs.

Zeniths are not super picky on float height (unlike DCOE webers).

 

[bernd_st]

Rick, as Rootes Racer stated the Zenith's aren't that picky on the float height setting. What I normally do is to adjust the float dry so that the needle valve just shuts off a tad bit before the float reaches horizontal position. As you say this needs to be adjusted by washers under the needle valve. At least from my experience that always works...

 

[rixter]

Thank you. I was guessing that there was probably some small range that is acceptable and that having both carbs being the same level would be important.

Rick

 

[bernd_st]

Indeed, having both carbs at the same float level would be recommended...

 

[beamdream]

My method FWIW is to have a length of clear (pvc) hose, about 3ft (metre) long, connected to the inlet pipe with a small funnel at the other other end.

I elevate the hose vertically to create a head of pressure and with a soup tin of fuel gently pour it in until the float rises and shuts off, then measure with my vernier ruler the fuel level from top of the float bowl.

Over the years I've come across different types of needle valves and used washers as necessary to get the right height