Two stroke motor without ENGINE OIL???

I recently bought a Echo PB-755 Backpack Blower to blow leaves in my yard.

I am very puzzled by it. It is a 2 stroke engine. Takes 50:1 oil.

There is no separate tank/port/opening for engine oil.

The manual has not a single word mention of engine oil (like 10w30 or whatever).

So, all indications are that this engine needs no oil.

I can hardly believe this as all gas engines I have seen so far needed engine oil.

Is my conclusion that the engine needs no oil, correct?

i
Reply to
Ignoramus1841
Loading thread data ...

RTFM. Yes, it needs oil. The oil is added to the gas.

Harry K

Reply to
Harry K

I actually did say that oil is added to gas. I did not miss it. I am surprised that there is no separate oil system, to oil all the moving parts. How are they lubricated?

i
Reply to
Ignoramus1841

you're kidding right? Are you thirteen? Have you never owned a 2 stroke engine before? The oil in the gas passes through the crankcase and does the lubricating before it goes into the combustion chamber.

s

Reply to
Steve Barker LT

on 10/16/2007 10:30 AM Ignoramus1841 said the following:

No separate oil other than the oil mix in the gas. The oil-gas mix lubricates all internal parts.

formatting link

Reply to
willshak

Correct. Do a Google search on 2 stroke engines and see how they operate. The oil mixed with the gas does the lubrication. There was a time (1950's?) that Saab made cars with 2 strokes engines too.

The advantage of 2 stroke is cheap to make, small, can be operated when not level.

Reply to
Edwin Pawlowski

Hi, You made my day!

Reply to
Tony Hwang

Hi, Leanr how 2 stroke motors work.

Reply to
Tony Hwang

Thanks a lot, guys. This time, I lived up to my screen name! Now I feel better about running this engine. My previous experience was with

4 stroke engines and diesels (Onan DJE repair and Cummins L423D repair). i
Reply to
Ignoramus1841

Iggy, I think you could rebuild the Space Shuttle singlehanded, and am surprised you don't know this one.

In a four stroke, you have valves. The combustion chamber and crankcase chamber are two separate chambers isolated from each other. The only time they cross over is bad rings, bad valve guides, hole in the piston, excessive wear, bad head gasket, etc. In a two stroke, the gas and oil go on both sides of the piston, and the oil in the gas lubricates the crankcase. Instead of valves, a two stroke has ports where the gas/oil mix moves from one side of the piston to the other. It's exquisitely simple. Google it up and get some diagrams.

Someone like you that has such a knowledge of how things work will get a real kick when you see simple diagrams of how this actually works.

Steve

PS: the router table is doing fine.

Reply to
SteveB

Plus it gives twice as much power for a given size than a four stroke. The power cycle comes every 2 strokes instead of every 4.

Reply to
jmagerl

Steve, yes, thanks, I have learned something very basic today!

i
Reply to
Ignoramus1841

Ignorant is just never having something explained to you. Stupid is having it explained to you, and not listening to the explanation. That's how we learn. We're born not knowing everything. Then, we're taught about this and that. Being stupid is choosing not to heed instruction.

Now you know.

Now that you've seen how it works, it IS exquisitely simple, isn't it?

Steve

Reply to
SteveB

The first two cycle I saw was a Bultaco Sherpa. A 200cc motorcycle. A local Harley club had a field meet at a dry lake. The Sherpa drew lots and lots of attention. Then, the boys on the Sportsters were challenging it to a drag race. With the incredible acceleration, the Sherpa would hole shot the Sportsters so bad, the Harley riders were embarrassed. Zero to sixty in something like four seconds. If they went far enough, the Sportsters would occasionally catch the Sherpa.

It turned a LOT of heads that day.

Steve

Reply to
SteveB

The fue/air mixture is ported so it contacts moving parts.

Reply to
Meat Plow

According to jmagerl :

Yes, two stroke gives out more power pound-for-pound, and usually CC-for-CC, but it's generally not exactly double for the same displacement. A lot depends on how it's intended to be used, and what it's been optimized for.

2-stroke, for example, usually emits a lot more unburned gas mixture than a 4 stroke does, given that each stroke does mixed duty - intake and exhaust phases overlap for example (both the gozinta and gozouta are open at the same time).

My small engines instructor custom tuned and raced type 3 two-stroke motorcycles and snowmobiles. Those had _ridiculous_ amounts of power.

[Unlike type 1 and 2 two stroke which do their intake/exhaust control via ports in the cylinder sleeve, type 3 does it with a rotating disk that you can tweak. Very high RPM/power ratings compared to other equivalent size two stroke. Quite rare these days.]
Reply to
Chris Lewis

Well said. Sometimes I go even beyond ignorant and do not listen well. Every time I do so, I get screwed in some way or another.

Yes, it is great. This blower is fantastic and cannot be compared to "consumer" models. (such as the one I had)

i
Reply to
Ignoramus1841

Steve, I couldn't have said it better!

I have a very low tolerance for stupidity, but in an increasingly complex world there are no more "Renaissance Men" and we're all ignorant of far more things than we could possibly be knowledgable about. So, I don't make fun of anybody's initial ignorance of any subjects they shouldn't have learned in public school.

I have no doubt that if iggy had chosen to study the engine more and maybe even disassembled it to see where the internal passages were he would have easily figured out why there was no separate lubrication system.

We're born not knowing everything. Then, we're taught about this

And also, as a friend of mine is fond of telling me. People are not born "good", they are born bad and have to be taught and trained to be good."

Just my .02,

Jeff

Reply to
Jeff Wisnia

So, this is your first weedeater?

What about a chain saw? Ever run one?

s
Reply to
Steve Barker LT

I see that you have the explanation how they work. I apologize for the 'rtfm' comment. Thinking back I was in the same position when someone told me that diesel engines don't have spark plugs...well, not after they are running at least.

Harry K

Reply to
Harry K

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.