Carb Cleaning Consolidated

The home of the FAQs and all the things you need to know to fix your Spree / Elite, outside the service manuals

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Wheelman-111
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Carb Cleaning Consolidated

Post by Wheelman-111 »

Greetings:

Here is the best photo sequence to see what's involved in carb cleaning.

Scroll down to the 4th through 7th photos, also the 9th and 10th. See the little brass pipe hanging alongside the inverted "tower" that holds the main jet? Therein lies the Pilot Circuit, and its outlet into the carb throat venturi was actually drilled by Honda-san using a calcified strand of spider web. Well, not really, but it's pretty small.

Few have seen evidence of this hole, None have photographed it. To see it, you must have a dark room, a bright flashlight and a good draw of Peyote smoke. Hold a finger over the main jet tower and shine the flashlight up into the pilot tube. Even then, it's a fleeting, mysterious little star in a dark sky. You almost have to look a little off to the side and align the beam with the rods, rather than the cones, of your good eye. If you see it, your carb is clean. If not, give it another bath.

Some say a guitar high "E" string fits through and serves as a resin-pusher to assist cleaning. If this scratches or enlarges the pilot hole, your carb may never work right again. I've always managed to get it clean with a 2-day soak in NAPA carb dunk.

For Float Valve issues, it has been my experience that an old float needle may not work, even if there's nothing outwardly wrong with it under the microscope. The price of a new one suggests it's made of gold-plated Platinum, but well worth it if your carb keeps overfilling. There's also the matter of the float needle seat, discussed Here.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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