# Echo Pb 260l Rpm Problems



## TownWrench (Sep 27, 2005)

*when Applyig Full Throttle Engine Does Not Stay At Full Rpm. It Revs Up And Hunts Or Surges Up And Down.this Carb Does Not Have Any Adjustments.also I Tryed Rebuilding Old Carb But That Did Not Work.also I Replacing The Carb With A New One And That Didnot Work. Any Suggestions?*


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## paulr44 (Oct 14, 2008)

If you have decent fuel flow to the carburetor, I'd say the engine has a crankcase leak somewhere. Could be an intake gasket, a crankshaft seal etc.
On a 2-stroke, the entire crankcase is part of the intake manifold, and any breaches in it will result in a diluted mixture to the combustion chamber, and therefore run erratically.

If you can keep it running with the choke partly or mostly closed, remove the air filter cover and filter (most draw in from the rear and can affect this test) carefully spray carb. cleaner (STAY AWAY FROM MUFFLER LEST YOU HAVE A FIRE) around the carb. to manifold, manifold to block and cylinder base gaskets one at a time while observing the RPM. If the engine RPM pick-up or dies down while spraying in one area, there's a leak there. Crankshaft seals could also be a problem, and if so equipped strato-port cover gaskets.
Paul


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