Two stroke engine orientation and durability
Two stroke engine orientation and durability
(OP)
In theory two stroke engines will operate in any orientation - how well does this work in practice?
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Two stroke engine orientation and durability
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RE: Two stroke engine orientation and durability
RE: Two stroke engine orientation and durability
Hydrae
RE: Two stroke engine orientation and durability
That makes it hard to start, not because the ignition is weak, but because you're starting out with a wet plug, and a super- high compression ratio, so it's physically hard to pull the rope. Sometimes I have to prop it up, upside down, to let the fuel drain out of the cylinder, which makes it easier to pull the rope, but it's awkward because you're pulling the rope down.
It's not the kind of super- dumb design feature that I normally expect from a Troy-Bilt product.
Mike Halloran
NOT speaking for
DeAngelo Marine Exhaust Inc.
Ft. Lauderdale, FL, USA
RE: Two stroke engine orientation and durability
RE: Two stroke engine orientation and durability
RE: Two stroke engine orientation and durability
The "diaphragm" carburetor solves the all position problem. And the fuel pick up freely falls into the various positions of fuel locations. I have seen the flooding problems in some engines, that is because of less turbulent areas of the crank case, and accumilation of oil in some areas. They seem to recover okay from the sudden over load. There isn't much leakage if any from the tank vent, I guess because of location and sizing. Since the fuel demands over ride the leakage.
RE: Two stroke engine orientation and durability
RE: Two stroke engine orientation and durability
like a Walbro or Tillotson, Zama etc.
These carbs are equipped with a small diaphragm pump and diaphragm operated metering valve, replacing the float chamber. The pump is operated by the pulses from the crankcase via a small gallery to the carb flange.
They are typically used in chainsaws, weedeaters, model aircraft, microlight aircraft etc., and so long as they use a "clunk" on the end of the fuel line inside the fuel tank, they always have a good fuel supply in any position.
There are seldom problems with these, and if there is a problem with fuel draining into the combustion chamber, then there must be a fault in the carb.
This type of layout has been successfully used since the fifties.
There is an increasing use of four strokes in these applications too, and there are various ways of getting around the more complicated issue of lubrication in these, - some brands have more successful ideas than others.
RE: Two stroke engine orientation and durability
rmw
RE: Two stroke engine orientation and durability
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RE: Two stroke engine orientation and durability
Some report poor starting from oiled plugs when the engine has been left a while, but no running problems or bearings.