I'm the 2nd owner and have enjoyed this mower for over 10 years. The carburetor is a metal, adjustable Wallbro LMR-10, and lately it's been lacking power at high rpm's. In the spring I replaced the ignition block and spark plug, I've checked that the exhaust ports are clean, and I just did a clean and rebuild on the carburetor. Could it be from the governor being out of adjustment from when I took the spring loose? Or, might it be the crankshaft seal(s)? Any other ideas?
Engine 1989 S21BSN lacks power
- Thread starter swainw
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Two-Stroke
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If it seems to operate at the normal RPM, then it doesn't sound like a governor problem. It's running at normal RPM but lacking the power it had before -- right?
Does the compression feel OK? Is it what you're used to -- knowing your engine for 10 years?
In addition to the crankshaft seals, look at the gaskets sealing the two halves of the crankcase. A two-cycle engine needs a tightly sealed crankcase.
Does the compression feel OK? Is it what you're used to -- knowing your engine for 10 years?
In addition to the crankshaft seals, look at the gaskets sealing the two halves of the crankcase. A two-cycle engine needs a tightly sealed crankcase.
Fireman 123
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I assume you mean its having trouble cutting the grass (bogging down)? If so, it could be the blade, cutting height, or dampness. Or if it simply doesn't run or sound right at full throttle, it's likely the governor is out of adjustment, or the choke is partially engaging if so equipped. Good luck.
It feels like the compression is OK, but I probably should check it. I'll also check the crankshaft seals. It's not the blade, grass height or dampness. I'll check the choke for being partially closed. Thanks guys.
Mowed with it today and it's power is back! I snugged up the 2 engine bolts from under the deck, close to the crankshaft (they were not what I would call loose, though), and I cleaned the oil residue from the spark plug. The other things I checked were OK.