Unknown tube on H70 7HP

[Bassman619]

Hello, I was hoping someone could tell me what this piece is for. It doesn’t seem to go anywhere. This is my first engine diagnosis so I have no clue

 

[tom3]

Old school crankcase vent tube. Newer engines have this run to the carburetor intake, keeps the EPA happy.

 

[Bassman619]

Old school crankcase vent tube. Newer engines have this run to the carburetor intake, keeps the EPA happy.

Ok, thank you very much

 

[Born2Mow]

You actually want that hose connected up to something. A breather works by reliving the pressure inside the crankcase caused by the piston going up and down. When the piston comes down the pressure is expelled, BUT when the piston goes back up dirt and debris can (and WILL) be sucked into the engine. If you connect the hose to the intake manifold, then you need a one-way valve, commonly called a PCV valve. So the best (cheapest, easiest) connection is between the air filter and the carb. In this way only filtered air can enter the engine.

 

[Rivets]

That tube was NOT designed to be connected to anything. The cover contains a filter behind the tube to filter the air. It was designed to hang just like you see it.

 

[Scrubcadet10]

You actually want that hose connected up to something. A breather works by reliving the pressure inside the crankcase caused by the piston going up and down. When the piston comes down the pressure is expelled, BUT when the piston goes back up dirt and debris can (and WILL) be sucked into the engine. If you connect the hose to the intake manifold, then you need a one-way valve, commonly called a PCV valve. So the best (cheapest, easiest) connection is between the air filter and the carb. In this way only filtered air can enter the engine.

if i remember right there is a reed valve in the breather assembly.
There is also a filter

 

[Rivets]

Some of the older Tecumseh engines, on the first Snow King engines, did not have a reed valve,

 

[Born2Mow]

That tube was NOT designed to be connected to anything. The cover contains a filter behind the tube to filter the air. It was designed to hang just like you see it.

And judging by the hours on the engine in the photo, that filter should have been serviced about 3 or 4 times... which is also part of the original design intent.

 

[Hammermechanicman]

It is not really a filter. The crankcase gas being expelled has atomized oil mist in it. The stuff that looks like a filter is there to cause the oil mist to precipitate out and drain back into the crankcase. If the stuff that looks like a filter is not there oil mist will be expelled from the engine.

 

[Scrubcadet10]