Echo vs Husqvarna

[CobyRupert]

I bought the CS501P. Nice size for general day to day cleanup and chores. So far no problems.

I will never understand why saws only need to be choked until that first burb! Then they run fine. Makes no sense to me.

Back to my question. So choke on a saw, is a choke in the sense that it closes up the throat, but doesn't affect the motor running in the same way as a typical four stroke. I mean, it makes no allowance for any warm up. Obviously, not required to stay running.

Yes, the choke is similar in that it closes (chokes) the air into the carb and cylinder.
My understanding is a 2 cycle uses the vacuum impulses of the piston to draw the gas into the carb, whereas most 4 cycles use a pump or gravity to get gas into a bowl (reserve) constantly kept full by a float (valve).

My understanding is you usually need a few pulls (pulses) to get the gas into the carb and cylinder to get the burp. (Thus my previous joke of "It always starts on the 1st pull! ...after the 2nd pull")
Until the gas gets there, you're just getting too much air, thus you need to choke the air off. (But why doesn't primer bulb eliminate need for 2 pulls before burp?)

I know that initially, when motor first starts, a lot of the energy (of the explosion) is going into heating the cold metal instead of being available mechanically. Not sure if or how this effects required air/fuel mix or necessity to choke until warmed up. Small 2 cycles warm up quicker. However, gas doesn't vaporize as well at lower temps so you need more gas than normal (or less air) when motor is cold. Thus: Choke.

 

[Industrial Toys]

Curious why no one ever made a Propane saw. Refill it from a BBQ tank. Never have a bloody carb issue again.

 

[Jstpssng]

Except that a standard small screwdriver won't fit most most recent model saws. Those that still have manually adjustable carbs all seem to have special screws that take odd-ball, specialty screwdrivers (splined, D, Double D, Pac-Man...). I guess that is supposed to keep us "regular folks" from adjusting the carb on our own. Fortunately, I have a set of those odd-ball screwdrivers.

The father/son team at the small engine shop which I go to files a groove into the screw, so that it can be turned with a normal screwdriver. They also generally are working on things which are off warrantee, and are one of those rare places which actually fix things when you bring them in. Unfortunately they bought a loader/dump truck and are getting into dirt work, so I'm not sure how much longer they will be there.

 

[Industrial Toys]

I was talking to the Small Engines Division Manager yesterday, being a customer (and friends) of mine. He seriously questions how long this type of business will be around with everything going "electric" Even ZERO turn mowers!

 

[Oldpath05]

Curious why no one ever made a Propane saw. Refill it from a BBQ tank. Never have a bloody carb issue again.

Possibly because the fuel tank would end up bigger then the saw............

 

[Oldpath05]

When it comes to those special screw drivers a bench grinder can make any screwdriver special.

The last time I seen them special carb screwdrivers was about 25 years ago at a local Husqvarna saw shop, I bought two of them but they have since vanished away just like the Husqvarna adjustable carb chainsaw, I dont know if Husky now makes any adjustable carb saw, think all there saws have gone Autotune. But in someways I kinda like that idea because now theres no more fiddling with those tiny screws even when the air filter gets dirty or if I loose track how far above sea level my tree is, my 550xp magically adjust itself.

 

[Industrial Toys]

For the difference in energy betwen gasoline and propane, I don't see the tank size being an issue. You could get creative and make the frame, the tank, or some such thing.

 

[two_bit_score]

I was talking to the Small Engines Division Manager yesterday, being a customer (and friends) of mine. He seriously questions how long this type of business will be around with everything going "electric" Even ZERO turn mowers!

That is something I hate to hear!

 

[gary49]

Curious why no one ever made a Propane saw. Refill it from a BBQ tank. Never have a bloody carb issue again.

A chain saw needs to be a two stroke for power to weight reasons. You'd need oil injection to run one on propane,I think. That would add weight, complications, and cost, not to mention that the saw would already be heavier due to needing a stronger tank to contain the propane.

 

[Deere Dude]

You could carry a backpack propane tank with a hose over your shoulder. Carrying a 30# tank in front of you would be prohibitive, for me at least.