Weber 40 IDF - flooding

Just been out for a run & on returning heard bubbling in the RH carb after switching off. Took the filter off & fuel could be seen above the butterfly & leaking out from the carb/manifold joint. I assume from this the float valve isn't sealing properly & needs a clean? Anybody else have any other suggestions? Carbs are 3 years old & have done 10,000 miles.

Yup.....sounds like crud in the pilot valve. I don't believe those have Nypro (rubber) tips, so remove the top of the carb and clean the valve and the well it sits in with aerosol carb cleaner and it should be OK.

Thanks Gordon: do I need new gaskets or can I reuse?

Mike you can try to reuse the gasket if it's not torn or amaged...If the gasket does not reseal, DO NOT USE SEALER of any kind....Get a new gasket....
Good luck....

Thanks Leon, I think I'll play safe with a new gasket.

Have dual Weber 44s and have experienced exactly that condition. (Actually I caught it late - after it had leaked so much gas that the #4 cyllinder was completely filled - but that is another story!) In process of chasing a solution, I installed a manual shut-off valve in the engine compartment. That instatntly worked, and only later did I figure the carb out.

The valve is easy to reach, but kinda hard to see - sort of a nice secondary security device now.

I never re-use carb gaskets below the top cover, or any that have been damaged (torn or separated) during dis-assembly.

Contrary to Leon's belief, I think it's a real positive to use (believe it or not) Chapstick on carb and manifold gaskets.

Just get the plain stuff, as the engine won't really care whether what you use is flavored or not, and it certinly doesn't need the medicated stuff.

Just use the stuff right from the tube - it's actually a very efficient delivery mechanism. As you apply it the gasket should turn a darker color so you'll know where it's been hit.

Why do this? Well, it helps moisten the gasket material to make it a bit softer and seal better when assembled, and later on if you wish to remove the carbs or manifolds it makes it much easier to get them to release, unlike Permatex RTV that seems to glue the metal parts to the gaskets causing the gasket material to tear and separate when removed.

Try it, you'll like it. (just don't use it on your lips after gooping up your gaskets).

gn

As Gord says, we've used Chap Stick and wheel bearing grease; both work real well.

regular engine oil works fine too

Neither Chapstick or wheel bearing grease are "sealers". Both will disolve in the presence of gasoline.....

OK, that's true, but the point is you're attempting to get the gaskets to seal properly and moistening them helps to do that.

Later on, when you wish to disassemble the metal parts for some reason, the gaskets should let go without adhering to the metal parts and coating them with a release agent when assembled seems to accomplish that.

I always used regular old automotive grease on carb and manifold gaskets for decades with great success until I heard about the chapstick idea from George Brown. I thought it was cool, tried it and damned if it doesn't work, PLUS you don't get all grease-goopy getting the gaskets ready.

my 2 cents.....gn

Float level was set well under the recommended 11mm . Cleaned & adjusted then screwed it all back together with a new float valve (this time with nypro tip), replacing the fuel line & filters but reused the gasket. All now OK. Will have a look at the other carb. in due course & plan to replace the mechanical pump with a rotary electric. I think I

Don't you just love happy endings?? And we all have nice soft lips now too, thanks to Gordon. Note: My personl preference for gasket and interface sealing, lubing or whatever you want to call it is Dow-Corning 4Compound, a semi-clear silicone grease. I got a tube of this at work about 20 years ago, and still have half of it left. A little dab 'il do ya. This stuff, or something similar would be great in this app. and will not disolve in gas, I do not think. I use it on oil filter gaskets, as it stays slippery vs. engine oil that can cook out and harden up, a little,,and make undoing a bit harder than it should be. Another good use is on the valve cover gaskets between the gasket and the head: never a problem separating. This is not a silicone adhesive, but a silicone grease.

$0.02 worth.