First major mowing (1.5 - 2 hrs) after spring maintenance (spark plug, oil & filter change, air cleaner & pre-cleaner), after an hour or so, engine started sputtering like it was running out of gas. After a few seconds, engine smoothed back out. Pattern repeated every few minuntes for the remainder of the job (45 minutes or so).
First thing Google turned up was improper venting/bad gas cap/vapor lock, so that's where I'm starting, but I don't know how the fuel tank is vented or what a good system is supposed to feel like. I'm assuming that the hose running between the air intake (point 1 on the attached photo) and the gas tank (point 2) is providing ventilation for the tank to keep the fuel flowing.
If I pull the hose at points 1 & 2 and try to blow through it, it feels about right for a 3/16 inner diameter hose so I don't think the hose is blocked.
If I pull the hose at the air intake (point 1) and try to blow through it with it attached at the tank (point 2), the hose seems almost completely blocked. I don't know how much air is supposed to be getting through the fitting on top of the tank, but my lungs weren't able to push any air at all through it that I could tell.
Pulling the hose at point 2 with it attached at point 1 (at the air intake), I can get air through the hose and the fitting at the intake. Not as much as through the unconnected hose but probably plenty enough to vent the tank.
So... if I'm supposed to have clear airflow into the tank at point 2, then that fitting on top of the tank must be clogged. I can't find anything on YouTube (or elsewhere) that describes the fitting or how to remove and clean it, and I don't want to hit it with the compressor until I know more about it and can get if off the tank.
Any thoughts on whether I'm on the right track and/or how to get the fitting off the tank at point 2?
First thing Google turned up was improper venting/bad gas cap/vapor lock, so that's where I'm starting, but I don't know how the fuel tank is vented or what a good system is supposed to feel like. I'm assuming that the hose running between the air intake (point 1 on the attached photo) and the gas tank (point 2) is providing ventilation for the tank to keep the fuel flowing.
If I pull the hose at points 1 & 2 and try to blow through it, it feels about right for a 3/16 inner diameter hose so I don't think the hose is blocked.
If I pull the hose at the air intake (point 1) and try to blow through it with it attached at the tank (point 2), the hose seems almost completely blocked. I don't know how much air is supposed to be getting through the fitting on top of the tank, but my lungs weren't able to push any air at all through it that I could tell.
Pulling the hose at point 2 with it attached at point 1 (at the air intake), I can get air through the hose and the fitting at the intake. Not as much as through the unconnected hose but probably plenty enough to vent the tank.
So... if I'm supposed to have clear airflow into the tank at point 2, then that fitting on top of the tank must be clogged. I can't find anything on YouTube (or elsewhere) that describes the fitting or how to remove and clean it, and I don't want to hit it with the compressor until I know more about it and can get if off the tank.
Any thoughts on whether I'm on the right track and/or how to get the fitting off the tank at point 2?
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