how to fix the float of a solex 40 pII-4

[JAIME CASTRO]

hello,

the gasoline enter inside the float ,and the carburetor doesnt run well ,my mechanic use a special glue to close again the float but is there another solution,more effective?

thanks

[David Jones]

Buy a replacement float. I would sell you one for $10 if you pay shipping and I am sure many others would do the same. Where are you? It always helps to know where someone is as sometimes there is someone close by you to help out.

[JAIME CASTRO]

ok David ,

contact in my email adress your bank account

[Gene Choin]

Always one to try to give a lesson to my kids, when my float was leaking I showed them!
First get all of the gas out of the float, then solder it up. Right?

I put it on the stove to heat it and let the gas vapor pressure force all of the gas out.
Of course, the vapors got to the flame and with a loud bang, sent the two pieces to the far walls of the kitchen.

My kids know about my scientific lessons and now show up with crash helmets and ear protection.

[JAIME CASTRO]

Hello Gene,

in Spain we have a expression for this

the translation would be "experiments with sparkling soda",so I prefer ths spare part.

thanks for your advice

[Bill Leavitt]

My kids know about my scientific lessons and now show up with crash helmets and ear protection.

LOL!!

If you don't want to blow your float to smithereens, place it in a pot of gently boiling water. This will vaporize the gas inside the float and release it in a somewhat more controlled manner. The stream of bubbles from the float will also show you where the leaks are located. Cool it down slowly so it doesn't collapse on itself (seen that). Then you can solder the leaks closed.

[Bill Leavitt]

Then you can solder the leaks closed.

Or rather, seal the leaks with something. I've been informed that the Solex uses plastic floats, which I guess is why Jaime said his mechanic used glue. I've never been inside a Solex, most of the floats I've seen and/or tried to repair have been brass.

Obviously you need some sort of patch that's impervious to gasoline. Maybe coat it with Kreem or some other gas tank sealer, or a dab of JB Weld?

[Rainer Cooney]

Of course when sealing or coating you are changing the weight of the float and thus it's abililty to float.

[JAIME CASTRO]

ok Thanks for the advices
a new float is fliyng from USA to Spain by mail not for the explosion of a home made repair.

[Bill Leavitt]

Of course when sealing or coating you are changing the weight of the float and thus it's abililty to float.

Float height settings are adjustable, and is something you want to check and adjust (if needed) anytime you're messing around inside the bowl. To me that's a given, but it doesn't hurt to say it either.

Obviously if you goop it up so much that it doesn't float very well then it's time to stop being cheap and just buy a new one.

[Albert Tiedemann]

The float from the subject carburetor, a Solex 40 II-4, is plastic. Soldering or JB weld has no relevance. A fuel impervious epoxy or fuel tank putty can be used to advantage in an emergency. I repaired a Zenith 32 NDIX float with epoxy on the return trip from the ECH 2007. Such a repair will increase the weight of the float and the design weight of any float is an important parameter in the system of fuel level management in the carburetor housing.

If you have a leaking float, the weight will increase dramatically and the amount of displaced fuel necessary to raise the float to the shut off position may be such that excessive fuel is dumped into the intake manifold resulting in a too rich mixture and poor performance.

If the float is repaired and does not leak, it will still float, abeit at a lower level due to the weight. This disparity from the design weight and its effect on the shut-off position is easily compensated on the subject carburetor by adjusting the elevation of the inclined ramp supporting the pivot point of the float. According to the little spec book, this float should weigh 7.4 grams. An increase in weight of 1 gram would require a displacement of 1.3 ml of fuel. The active portion of the float chamber in the subject carburetor is a rectangle of about 40 x 44 mm. So, just due to the increased weight of the float, the fuel level rises about .8 mm. If you look at the cross section of the Solex float, find it to be a T-shape which you could approximate as two rectangles yielding about 850 square mm. To displace the above volume it would be necessary for it to sink about 1.5 mm. Estimating the center of bouancy of the float at 40 mm from the pivot and measuring the reaction point of the needle valve at 10 mm from the pivot, there is about a 4/1 ratio of fuel level to needle valve plunger displacement. The effective fuel level rise would be .8 + 1.5 = 2.3 mm without correction. So, if you globbed on a lot of sealer you might run out of ramp to correct the fuel level to specification. Best to get a new float at the correct design weight and all will be well as several have suggested.

BTW Bill, do you know the cheapest part on a Porsche?

[Jack Staggs]

If that is the case, put a thicker gasket under the needle and seat in the meantime.

[Bill Leavitt]

BTW Bill, do you know the cheapest part on a Porsche?

No, I haven't found that one yet.

G'head, tell me. I've got no shame, don't mind being the butt of a joke.

[Bill Leavitt]

BTW Bill, do you know the cheapest part on a Porsche?

No, I haven't found that one yet.

G'head, tell me. I've got no shame, don't mind being the butt of a joke.

For those waiting for the answer, it's "The owner." -ba-da-BOOM!-

My Scottish roots have betrayed me once more! -lol-

[Pascal Giai]

What is the best way to fix the float on a Solex 40 PII-4 ?
I will prefer to repair what I have, at least try before to get something else...
Is there a good reproduction for sale somewhere ???

My car was running poorly in town, one float was almost full of gas ( Low mileage carburetor )...

Thank you for your help !!!

Pascal Giai