r7000
Well-Known OPE Member
kind of a rudimentary question(s), I think I already know the answer some, but want clarification to be sure and a good understanding of the whole process ...
small engine 2-stroke, uses the downward stroke of the piston as a pressurization signal...
- which always goes to carb? this pressurization signal works the fuel pump (thing?) in the carb, how does the carb pump fuel?
- on small engine 2 stroke carbs there's [always?] 2 hose nipples? one is the intake from the gas tank that in fuel into the carburetor that is then metered by the carb and makes its way into the intake of the engine. The other nipple on the carb is what?
- Gas is sucked or pushed into the carb?
- If pushed then the gas tank must be sealed so it can be under pressure then correct, if so how much pressure and how is that pressure regulated?
- Does the gas tank need a vacuum break?
- Is the vent on the gas tank a vent to allow excess pressure out, if so at what value psi, or a vacuum break to allow air in as fuel as used?
- How does the primer bulb function, in what direction regarding pressure?
- wow can some 2-stroke engine designs that don't have a primer bulb work/start ? an old stil av011 chainsaw for example
- my understanding is the 2 "main" makers of carbs are ZAMA and WALBRO? all the aftermarket ones on amazon/ebay are just chinese knockoffs but operate on exactly all the same principles?
- anything on elaborate intake mechanisms on certain machines that supposedly increase performance, (something on my Poulan PL4218 and extra boot?) on how they work
examples - my 2-stroke poulan PL25 trimmer, stihl KM90r trimmer, stihl BR600 backpack blower, chainsaws, etc.
any information on anything related to what I mentioned, interested in getting a complete understanding.
small engine 2-stroke, uses the downward stroke of the piston as a pressurization signal...
- which always goes to carb? this pressurization signal works the fuel pump (thing?) in the carb, how does the carb pump fuel?
- on small engine 2 stroke carbs there's [always?] 2 hose nipples? one is the intake from the gas tank that in fuel into the carburetor that is then metered by the carb and makes its way into the intake of the engine. The other nipple on the carb is what?
- Gas is sucked or pushed into the carb?
- If pushed then the gas tank must be sealed so it can be under pressure then correct, if so how much pressure and how is that pressure regulated?
- Does the gas tank need a vacuum break?
- Is the vent on the gas tank a vent to allow excess pressure out, if so at what value psi, or a vacuum break to allow air in as fuel as used?
- How does the primer bulb function, in what direction regarding pressure?
- wow can some 2-stroke engine designs that don't have a primer bulb work/start ? an old stil av011 chainsaw for example
- my understanding is the 2 "main" makers of carbs are ZAMA and WALBRO? all the aftermarket ones on amazon/ebay are just chinese knockoffs but operate on exactly all the same principles?
- anything on elaborate intake mechanisms on certain machines that supposedly increase performance, (something on my Poulan PL4218 and extra boot?) on how they work
examples - my 2-stroke poulan PL25 trimmer, stihl KM90r trimmer, stihl BR600 backpack blower, chainsaws, etc.
any information on anything related to what I mentioned, interested in getting a complete understanding.
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