There is a TL;DR version if you want to skip to it.

I'm new to 914world, I think. I was on a few sites back when I first got my 914. I was on Rennlist after it was no longer porschephiles, but when it was still a listserv through the move onto the web. my old page Rennlist page but I've lost the account info and haven't had that email address in years. Several moves and marriages resulted in a lot of non-driving time for the poor little car.


Anyway, that's in the past. In the present I have some carb issues I am asking for help on. Carbs are Weber 40IDA3C. I've been chasing idle problems for a while. I installed a Pertronix Ignitor and their coil, new plugs and the card would idle. Yay, problem solved, for a while. Then the car sat a lot for another year, I got a new job in a place with warmer weather (Houston) moved there, and now am trying to drive it around a bit more. Now sometimes it would idle, but mostly it idles for a bit under a minute, then slows down and dies. Runs poorly at low/mid throttle and RPM, runs well with more throttle and RPM. I pulled out and cleaned the idle jets and the idle mix screws. I sprayed it all out with carb cleaner, then pulled it out of the garage and with the air cleaners off, I could hear and then see that fuel was running into the carb throats, filling up the venturis above the butterflies. I pulled the top off the carb and started troubleshooting. I found that one float doesn't float. It is partially filled with fluid. And there was a bunch of crud in the bottom of the float bowls. A lot of it in the bad float's bowl was green, so I kind of know what happened there. So I need a new float. Who does the forum recommend for carb parts?

TL;DR start here
40IDA3C

But my bigger question is about bushings. With the float overfull, I had fuel on the outside of the carburetor. It did not seem to be coming from the top. I am suspecting the throttle shaft bushings. Is there a good way to test this? And again who is recommended to do carb work? Is this something an amateur can do without a machine shop? Should I just expect to send it out anyway since the crud indicates the possibility of other corrosion and issues?

Several things come to mind;
Wrong fuel pressure...too high,
Water in fuel,
Dirty rusted fuel tank.
You can repair the float with solder if you find the leak,when you have fixed all the issues run it up and see how you go ,best to fix all the existing issues and go from there before you head to an expensive rebuild of the carbs,good luck.

start at Performance Oriented. Read all of the technical info there. Sounds like you need to start from scratch and Paul Abbot is the man to guide you through the process and supply parts

For parts and info
http://youroil.net/weber_carb_parts.html

Webers work good but they need to be in good order.
Bushings once worn I would send them to Performance Oriented but it's not cheap. Bushings you look for play side to side and thrust, then take the carbs off and look for carbon tracing on the butterflies.
Float level is critical but if you want to DIY there is info at the 2 sites you have been given.
Fuel pressure is also important you need a good regulator and set it for 3lbs.
There are also orings and gaskets that must be in good order.
The carbs must be clean.

The emulsion tubes, jets, venturis, etc must be set up for your engine, most carbs that haven't seen work are set up for a 2.0.

You need to do a lot of reading.

Other Weber parts sources include:

Porsche Mail Order (PMO). same source as above.
Pierce Manifolds
partsklassik.com
WeberCarbsDirect.com

Soldering leaking floats may change the weight and thus the bouyancy of the float.

There's a mechanical spec for float level as well as a PMO float level inspection guage that installs in the exterior float drain opening for active display.

All throttle shaft wear surfaces must be within spec in order to set up carbs correctly.

Much Weber 3-barrel setup, diagnosis and advise on PelicanParts tech 911 forum.

Sherwood

my recommendations are similar to above

you can rebuild the carbs yourself.... but likely not the throttle bushings

they are not cheap!

if it were me, I would buy a float
rebuild them probably to clean everything
then set the float levels and linkage
and test them

this is all relatively affordable and for a few hundred-ish you can buy the float gauge, parts, gaskets

then after running and balanced, and tuned...
check your throttle bushings

you can feel them when they are leaking
hopefully your leak was out the top
and usually the throttle bushings are only leaking air (not fuel)
usually you won't have raw gas sitting on top of the butterfly once you fix your float issue

I think I spent 1800 on throttle bushings when I used performance for that repair ? don't remember exactly as its been a few years

The float won't be upset with that tiny dob of solder ,besides they are hard to find and you can set using float gauge tool.
I really think if the OP cleaned his carbs out and ran thru the basic (correct) baseline setting he may be ok.
The reason he has fuel leaking out the spindles is overly high fuel pressure,this is the #1 cause for this as most people use a fuel pump with too higher pressure,3.0 to 3.5 PSI is plenty.

Thanks for the help.

I've learned a bit more from the links posted and it looks like my best bet now is to drill out the lead plugs and give everything a good cleaning. then try again with a new float and fuel filter. I seem to have a little play in one of the throttle shafts, so it may have a full rebuild in its future, but I'm not so sure my budget does, so I'll see how it runs with everything else fixed first.

To address a few possibilities raised:
The carbs are jetted at least close to correct for the 2.4. I did that when I built it.

The fuel pump and regulator are low pressure units from Holley, but the fuel did seem to be squirting out the needle valves pretty hard, so I'm also going to grab a fuel pressure gauge to test it. Maybe something failed.

I'll probably buy new one, but how does one solder a bad float? Mine still has fuel inside it that would need to be purged first. I am really, really reluctant to put metal-melting heat to something full of potentially flammable vapor.

1. use a soldering iron - not flame

2, drill a hole in it and drain the fuel, purge the vapor by blowing nonflammable aerosol into the float

3. use that hole to pressurize it enuf to find the leak in a tub of water

4. solder both holes

(we routinely soldered gasoline tank leaks "back in the day" after flushing with water & flashing the vapors)

OR - just use an epoxy fixit like they sell for boat gas tanks

In the long run, spending the money up front to have Performance Oriented rebuild the carbs will solve any carb issues and you can cross that off your list. A lot of these carbs are now pretty old and the ethanol laced gas doesn't help in cars that sit or are stored over winter.

Remember, 90% of carb issues are ignition oriented, so be sure to check that as well.

After recent experiences by others on the board with them, I'd avoid these guys. They just seem to be resellers and will just ship you whatever they get, and it's up to you to sort out any problems it may have.

--DD