What is this?

[jakev]

Hello, all.

I've attached a photo of a part from my engine that I don't understand its purpose. It is a plastic tube that attaches to the rear of the engine sheet metal. The plastic tube is connected to a hose which connects to a fitting on the bottom of the air box. So, what is its purpose? It almost seems to be a drain line.

[Tim Walsh]

My wrench said it was for catching oil, but honestly he if he said it was for catching stray muffler bushings and it still wouldn't have made much less sense. The bottom rubber peice was cracked on mine so I left it out.

[jpnovak]

It is the oil catch. It is usually attached to the lower most port on the T on the bottom of the air cleaner. Its to catch oil that comes over from the breather tube next to it.

[Jim Sims]

It is the drain line from the bottom of the air box or air cleaner. It allows whatever ends up in the bottom of these housings (usually oil from overfilling the oil tank) to be drained to the ground instead of being dumped onto the top of the engine. The rubber duck bill like bottom piece on the vertical plastic tube acts like a one way valve. Replacement parts are still available. Jim