Weber Float Setting Question
 

After reviewing the archives and checking out my Weber manuals and 101 Projects, I have but one question.....

What is the correct measurement for the depth of the needle valve?

- I know it is supposed to be 18.0mm +/- .1mm but does this take into account the gasket between carb top and base??

- The diagrams I have, show that the needle valve housing drops a bit from the outer top flange (to take into account the gasket) but my carb top is flat accross - is this correct?

Thanks for a reply - i just want this to go back together today and get the tuning done.


Regards,
Andrew M
1970 911T

the only way i know how to do it is with the factory tool.

Nice - but where can I find one? I can't seem to locate it at Pelican...

Andrew15,
There's also a Weber mechanical jig (a plate and screw) that sets up the preliminary float setting while the carb is apart (not sure if it's still available). If you're just replacing the factory inlet valve, use the float level tool shown in John's pic as it's essential to verify and fine tune the float level. Aftermarket inlet valves may require a different initial setting.

Sherwood Lee
http://members.rennlist.org/911pcars
www.seinesystems.com

the tool is available from PMO, Performance Products, Tweeks.

Sherwood

If you have a drill press, or are very steady with a drill, you can make a device that will do the same thing as the Weber tool and save a lot of money.

Take a bolt that screws into the float bowl drain hole, and drill a very small hole through the head and down the shaft of the bolt. With a larger drill bit, enlarge the hole on the bolt head side.

Get a plastic or metal "T" vacuum fitting. Then epoxy the "T" fitting on the bolt with the center of the "T" in the hole in the bolt. Get some clear plastic tubing and attach it to the "T" on the upwards section and mark it at the desired level. Cap the remaining port on the "T" with a vacuum plug or piece of hose with a bolt stuck in the end.

Attach to the carbs, turn the key on and let the pump fill the float bowl and you can see the level in the plastic tube. Make four of these puppies and you can see the levels in every carb bowl at once and make them the same. Results in a smoother idle...

The things that we do to make the car work when the factory tools are not available or are just too expensive! I used a fitting like this for years on my Webers and works very well and at a cost of under two bucks. The factory tool was $40 or so the last time I looked for one.

JA

Here is a pic of one I had laying around for the last 20 years. If you look closely you can still see the mark on the short tube that was the desired fuel level.

Is it as nice as the factory tool? No, but worked fine and a lot cheaper!

Joe