|
|
Post by paintgiant on Jul 25, 2011 19:52:01 GMT -5
Correct, this time around I want to start simple, seeing as I made a simple mistake before, and work towards something that may be more complex in terms of diagnosis. Saw starts great and runs great with the choke open pushed in butterfly open. It will run and start to hiccup a little as the choke is pulled out butterfly closes. Once the butterfly is completely closed the saw stalls and stops. Keep in mind I am using the NGK plug from an echo repair kit. Plug appears to be the same size as the plug I pulled from the saw when I received it. Spark is blue on this new plug.
*Fuel is fresh 1 day old, 89 octane mixed with stihl 2cycle oil at a 32:1 mixture
|
|
|
|
Post by tribulation138 on Jul 25, 2011 20:23:26 GMT -5
the saw is running completely normal buddy.
to start a cold engine:
pull the choke out. pull rope till it fires once or quickly dies.
push choke in. pull rope. saw should run.
saw should not run with choke pulled out. if it does you have a air leak.
the point of the choke on is to prime and get proper fuel to start and fire engine that is it. saw should only be ran with choke button in. always shut off saw with switch.
|
|
|
|
Post by MCS on Jul 25, 2011 21:03:50 GMT -5
Same as Trib, I don't get what you are doing with the choke.. The choke is only closed while cranking. With the choke closed, after a few cranks with the rope the saw will start but die. At this point you leave the trigger latch on but open the choke and crank it again and it should start and run. If the saw is running and you pull the choke lever out the saw will die - it will be flooded...
|
|
|
|
Post by paintgiant on Jul 25, 2011 21:03:51 GMT -5
Thank you much, it would appear my understanding of a choke was fubar. Just to reiterate so that I have proper understanding. When the choke is closed i.e. butterfly closed (--) the venturi effect in the carb is amplified allowing more fuel to be pulled in for the initial start, this mixture of air/fuel is richer than the saw needs to operate. After the initial burn the carb is primed with fuel vapors. At this point choke is open i.e. butter fly open to allow maxiumum air into the carb and make a leaner mixture of air/fuel for the engines maximum effiiciency. Guess all I need to do at this point is read the carb adjustment sticky and tune my carb. Thanks again you guys have been a big help.
|
|
|
|
Post by MCS on Jul 25, 2011 21:14:16 GMT -5
Actually, with the choke closed, there is no venturi effect because there isn't enough air flow through the venturi. What really happens is there is a low pressure created in the carburetor but atmospheric pressure operating through the small hole in the diaphragm cover causes the diaphragm to force raw fuel into the carburetor through the ports.
|
|
|
|
Post by paintgiant on Jul 25, 2011 21:18:16 GMT -5
Ok that makes sense now thank you guys I appreciate you putting up with my ignorance, I now have a good understanding of how it all comes full circle.
|
|
