Weber woes, Please save me from insanity Options

[wbgoggans]

I’m at my wits’ end with my Webers.

They’re a pair of Spanish 44 IDFs. I’m running a fuel pressure regulator set at 2.5 psi, have set and verified float levels at least half a dozen times, and have rebuilt them again, and again, and then again for good measure.

Despite all of that, I’m still getting fuel in the crankcase.

For the life of me, I cannot figure out where the fuel is coming from. At this point, I’m so frustrated that I can’t tell up from down anymore, and I don’t feel like I’m following a logical diagnostic path.

Before I bite the bullet and spend $1,000 on a new set of Webers—or $400 on some Chinese knockoffs—would anyone be willing to take a look at these carbs? I’d be more than happy to pay shipping both ways and compensate you for your time if you can figure out what’s going on.

I’ve got a serious case of sunk-cost fallacy at this point, but more than anything I’d just love to understand what I’m missing so I can finally sleep at night.

For those about to suggest the basics: fuel pressure has been verified at 2.5 psi, float levels have been set and rechecked multiple times, the needle and seats have been inspected and replaced, and the problem persists. The fuel tank sits lower than the carburetors, so gravity feed should not be a factor.

Thanks in advance for any help or suggestions.

[Osnabruck914]

I’ve had real Webers, knock off Webers, and Solexes on different cars over the years. IMO nothing beats Dellortos. Spend your money on them, you won’t regret it.

Osnabruck914

[930cabman]

I have been a Weber guy for several decades, always the Bologna variety.

Possible float chambers are leaking when the engine is shut off?

They have kicked my a** more than once, but being me I never give in

best of luck

[DennisV]

I’m running a fuel pressure regulator set at 2.5 psi, have set and verified float levels at least half a dozen times, and have rebuilt them again, and again, and then again for good measure.

would anyone be willing to take a look at these carbs? I’d be more than happy to pay shipping both ways and compensate you for your time if you can figure out what’s going on.

How confident are you that the pressure regulator is accurate?

You could send them to Mike Pierce at Weber Carburetor Restoration.

[Jack Standz]

How do you know fuel is getting into the crankcase?
What are the symptoms?
Have you looked down the throats with the fuel pump on and seen fuel dribbling into the motor (and then the fuel is getting past the rings into the crankcase?)?
Maybe the float is set so far off that the needle/seat doesn't close and the bowl(s) overflows? What are the floats set at?

You would think that if raw fuel was getting into the cylinder from high pressure over powering the needle/seat, the motor would hydrolock. Not good and not really what you described.

There have been times where incorrect plumbing has caused a similar problem with cars we used to own. Had a Toyota Celica GT we bought with a motor so full of gasoline that the motor would not turn. Smelled terrible, like fuel (IMG:style_emoticons/default/smile.gif) . Drained the "oil" which was mostly gasoline, flushed with some fresh oil and she was fine.

Maybe fuel is coming in via an incorrect fuel line attached to a stuck PCV valve or something? Just guessing here. That's unusual for significant fuel to make it to the crankcase.

[Ninja]

What engine are you running these on?

What venturis are in the carbs?

Mains/airs/idles?

Those carbs are too big for a 9.0/1 mild cam 2.0L unless you're running it near redline (competition engine).

Excessive fuel in oil is one of the symptoms of improper size selection.

Now, those are perfect for a stroker engine above 2.2L.

Even with the big engine you will probably have to downsize the venturis over the stock ones that came with the carbs for a street application.

What condition is your engine in?

[Chad911sc]

(IMG:style_emoticons/default/agree.gif)
I agree with Ninja.
My 2056 wouldn’t run correctly through the transitions in my Spanish Webers until I put the 28 vents back in it. And that’s on 40 Idfs. I did end up getting it tuned in nicely with some 30 vents, but it took a lot of trial and error to get there. 44’s are big for 2.0

[wbgoggans]

(IMG:style_emoticons/default/agree.gif)
I agree with Ninja.
My 2056 wouldn’t run correctly through the transitions in my Spanish Webers until I put the 28 vents back in it. And that’s on 40 Idfs. I did end up getting it tuned in nicely with some 30 vents, but it took a lot of trial and error to get there. 44’s are big for 2.0

A few more details to answer some of the questions:

My fuel pressure regulator and gauge are both brand new from Summit. Both have good reviews, so I’m reasonably confident that the pressure reading is accurate.

I know fuel is getting into the crankcase because the oil level is rising, the oil is noticeably diluted, and it smells strongly of gasoline. I’ve also placed blue shop towels between the carbs and manifolds overnight. When I return the next morning, there are noticeable fuel stains on the towels. This morning, I repeated the experiment with the fuel pump turned on, and the towels were soaked within five minutes.

My float level is currently set at just a hair over 10 mm.

As for jetting, I know the venturis are 28 mm and the idle jets are 55s. I believe the mains are 110s with 190 air correctors, although I don’t have my notes in front of me at the moment.

I’m aware that 44 IDFs are larger than ideal for a 1.7. However, from what I’ve been told, the 28 mm venturis should make them reasonably manageable. I’d certainly be interested in hearing others’ thoughts on that.

That said, I don’t believe my primary issue is simply that the engine is running rich. Fuel is literally leaking from somewhere even with the engine not running. If I turn on the fuel pump and let the car sit, fuel eventually finds its way out of the carburetors, down the manifolds, and into the engine.

[Superhawk996]

Take carbs off car

Place on paper towel

Fill float bowl - leave top cover & float off

Determine where fuel is leaking from into the throttle bore:

Dripping out the idle circuit ?
Dripping out the main ?
Dripping out the accel pump nozzle ?
Weeping through the casting ?

[930cabman]

Take carbs off car

Place on paper towel

Fill float bowl - leave top cover & float off

Determine where fuel is leaking from into the throttle bore:

Dripping out the idle circuit ?
Dripping out the main ?
Dripping out the accel pump nozzle ?
Weeping through the casting ?

(IMG:style_emoticons/default/agree.gif) quick simple easy to narrow the issue

[wbgoggans]

Take carbs off car

Place on paper towel

Fill float bowl - leave top cover & float off

Determine where fuel is leaking from into the throttle bore:

Dripping out the idle circuit ?
Dripping out the main ?
Dripping out the accel pump nozzle ?
Weeping through the casting ?

To be honest I have not been able to determine where the leak is I think that’s the really maddening part of the whole ordeal. I have just purchased some food dye to put in the fuel bowl. I will update in the morning!

[bkrantz]

After too many years with carbs, the only Weber in my life that uses gas makes grilled burgers and salmon.

[Jack Standz]

Well, didn't think of mentioning that it could be a crack in the carb. Is it both carbs or just one?

Can definitely feel the frustration. Had a fuel delivery problem a while ago on the '74 after rebuilding and installing a new motor. Went through multiple fuel pressure regulators, multiple fuel pumps, and fuel pressure gauges. A brand new gauge would start out at just under 3 psi and after the motor warmed up it would show -0- psi! This caused lots of parts swapping of FPRs, pumps, plumbing, etc. Turns out it was a crappy gauge.

Also, since you mentioned you rebuilt the carbs, did you make sure the top gasket was the right one? Have seen so many ones that are slightly different. Maybe hold the new one up to the original gasket and see if they are exactly the same.

Also, you can cut a slender piece of paper or thin cardboard that you can insert in the top of the carb to see where your fuel level is in the bowl (or a Q-tip (IMG:style_emoticons/default/smile.gif) ).

[Ninja]

(IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif)

Both the Hawks suggestions and Jack's "dip stick" suggestions are spot on.

Some carbs come with a sight glass in the float bowl for level checks.

This is a GOOD feature in my book!

Sometimes it is damn hard to gauge float weight on a solid float.


I have had ZERO luck with aftermarket carb parts in the last decade. Nothing is correct.
You can't keep the needle and seat from leaking.

Drives me bat-shit crazy@! (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif)

Real Weber junk is available from Pierce Manifolds.


You are running those on a box stock 1.7L.

You will end up hating yourself...

Even if everything is perfect those carbs will give you fits trying to provision them into an engine that has 40% less flow than they require.

You need 40s with the very smallest venturis (maybe 27s) available and you will still be over-carbureted on a 1.7...

It is FAR easier to use carbs that are too small than too big. (IMG:style_emoticons/default/ninja.gif)

[wbgoggans]

This post has turned into more of a rant than anything, so for that I apologize.
Last night I stuffed paper towels into the secondary venturis and they were stained this morning, so maybe they are leaking overnight? Oddly enough, this morning I couldn’t find anything actively leaking with the fuel pump running.
I really should have made this post sooner. I’ve been dealing with this problem since the car first ran back in February.
I got this car when I was 16, back in 2020, and god damn, I just want to drive it.
The cycle has basically been: “Ah, it must have been the floats!” Adjust the floats, change the oil, drive it, realize it’s still flooding, add a fuel pressure regulator, change the oil again, try tuning the carbs, maybe drive it a mile down the road in absolute nirvana because my six-year-long project is actually moving under its own power, think, “Wow, this is awesome,” and then return home only to discover that there’s still a fuel problem.
I first rebuilt these carbs as a completely unsupervised 16-year-old after buying them on Facebook Marketplace from a guy who claimed they never worked right on his buggy. Being young, naive, and completely obsessed with hearing the kickass Weber induction noise, I figured, “Surely I can figure this out.”
Since then, I’ve probably had these carbs apart 30 times and spent around $700 with Pierce Manifolds replacing everything except the actual carb bodies themselves (remember when I mentioned the sunk-cost fallacy?). And honestly, I kind of did figure them out. The car has driven on these carbs and, at times, has run pretty damn well.
I’ve watched every YouTube video I can find, read countless forum posts, and probably gone through my Weber manual two dozen times. The problem is that all of my carburetor experience has been built on fixing my own mistakes. I’ve never actually seen what a properly sorted set of IDFs is supposed to look like or how they’re supposed to behave on the car.
With the help of this forum and others, I’ve learned so, so much, and I’ve genuinely loved the process. But at this point, I think I’ve finally reached the limits of my own curiosity and knowledge. It feels like these carbs are the final roadblock standing between me and finally driving this car after six years.

[BillC]

Since you've mentioned the sunk-cost fallacy several times, maybe it's time to stop messing around with those webers altogether. Maybe find a set of carbs that are correctly sized for your engine. Maybe buy the parts to reinstall the factory D-Jet into your car. Maybe contact PMB Performance and buy their "drop in" fuel injection system -- you'll need to install a high-pressure fuel pump and get replacement intake and fuel rail parts, but you'll be amazed at how nicely the car runs with it.

Did your car come with carbs, or did you install them? Any chance you still have any of the original fuel injection parts?

[Nogoodwithusernames]

I can't help much with carbs, haven't had anything with a carb in 10 years. Since I sold a VW kit car and got my 914.

How much of a VW/Porsche car scene do you have down in GA? Might be worth talking to a few people or making a few calls to clubs to see if anyone could help you out? I'm even thinking maybe see if anyone has a car running carbs and swap them from car to car to see if the issue follows the carbs or the car? Like others have asked, is it both carbs or just one side?

Good luck with the troubleshooting and hope you can get out and drive some more soon!

[IronHillRestorations]

There’s so many bad things that can happen to a set of carbs that are best suited for a high performance application. Plus, 44’s are not the right carbs. If your oil is diluted to the point of raising the oil level, you are ruining your engine.

Based on your posts, you know they are not right, the guy who sold them to you even told you that. Sounds like you got stuck with a bad set of carbs and you don’t want to admit it. You have the wrong size carbs anyway, but you don’t want to admit that either. I don’t intend to sound rude, but repeatedly taking them apart multiple times without a positive result isn’t the solution.

All that said, I’m curious if the fuel inlet valves are seating properly, how you set the float levels, the fuel pressure, and if the carb body is cracked somewhere.

[wbgoggans]

I really need to thank everyone for their advice and words of wisdom, not only on this thread but for the overall treasure trove of information, kindness, and generosity that this forum provides.

This project never would have been possible without this forum, and god damn do I love this stupid old car.

You are all right—I probably should have bailed on these carbs a long time ago.

I’ve decided to list them on eBay. I’ll include the link below, and I’d appreciate it if you all could let me know whether the listing seems fair and accurate.

Also, if anyone has a pair of Weber 40 IDFs ( or dells) for sale, please let me know. I’d much rather buy a known, properly functioning set from someone in this community than roll the dice again.
https://ebay.io/m/MJRPd6

[brant]

Take carbs off car

Place on paper towel

Fill float bowl - leave top cover & float off

Determine where fuel is leaking from into the throttle bore:

Dripping out the idle circuit ?
Dripping out the main ?
Dripping out the accel pump nozzle ?
Weeping through the casting ?

(IMG:style_emoticons/default/agree.gif) quick simple easy to narrow the issue

(IMG:style_emoticons/default/agree.gif)