Toro Lawnmower Air Filter: Additional Small Diameter Tube; Purpose ?

[clare]

Magnetron is the trade name for the electronic ignition unit on Briuggs and Startton engines over the last 30 or more years.

[mike]

The port is drilled into the INSIDE of the venturi area. The tube moves the input toward the air filter, but still inside the carburetor at all times. At no point does the port or the tube exit the inside of the carburetor. Scratch that, the tube extends slightly into the air filter, so that's technically outside the carburetor venturi area. The effect is the same. The cleanliness of the air is the same either way. The differential pressure in the bowl might be affected by the tube.

[Taxed and Spent]

Wow, that's plenty weird. Why don't they just call their riding mower a space ship?

[clare]

That is true IF as you state the "tube" is part of the carb, and no hose is involved. This is true on some carbs - not true on some others. It DOES keep the pressure in the float bowl equal to the pressure at the inlet of the ventury, which in practice doesn't make a lot of difference at cranking speed but could affect mixture at speed if the ait filter is restricted.

As the OP was asking what happened if the "tube" was notinstalled I was ASS U MEing this was a removable, external part. Perhaps he was asking what would happen if he modified the carb by yanking the yube out and plugging the hole? Just pulling the metal tube out, leaving the hole, would make a very negligable difference.

[clare]

Briggs didn't MAKE riding mowers 30 years ago. They just made engines and sold them to companies like Murrey, who made tractors and didn't pay for the engines, so Briggs "inherited" Murray - and now makes lawn tractors.

[Taxed and Spent]

Wow, that's plenty weird. Why don't they just call their engines "rocket motors"?

[mike]

That statement confirms that we have no idea what it does. It's a removable internal pipe. I can't imagine a vendor adding a part that does nothing. Its very presence indicates that something is going on. Would be interesting to know what.

[clare]

Because Oldsmobile had that brand name locked down from back in the fifties???

[Diesel]

Briggs calls one of their ignition systems a 'magnetron'. Not to be confused with the one in your MW oven mind you. It has a magneto like you'd expect, but doesn't use points and a capacitor to complete the circuit for the plug. Instead, it's using transistors. It's more dependable and some individuals claim it results in easier starts. The entire unit is called a 'magnetron' ignition system.

I think (but very well could be wrong) that they call it a magnetron because it's using a magneto with solid state electronics to control the plug vs the old point system.

And let's face it, Most people these days don't know how their microwave oven works or the names of the major components inside. They just know if they push buttons, they get popcorn or a 'hot meal' I would call this the dumbassification of America, but I've only visited a couple of other countries (job related) for a short while so have nothing to really compare it against.

[steve]

I think it vents the float bowl, if you put your finger over it while mower is running it will die.