OK - Now its Oil!

[Cicero]

Harley,

I will make sure to use a higher octane bearing grease the next time my bearings begin to prematurely ignite inside their cage. Thanks for the revelation.

 

[tundraotto]

hey big make sure you use that high quality bearing grease in your chainsaw as it is a 2-stroke motor that uses the fuel/oil mix to lubricate your bearing. make sure you do not neglect to tell us what bearing grease stays on the main bearing at 14k+ rpm...

ps. fish (aka. tundraoctane) lol, i heard about you lol

 

[Harley]

BIG CICERO wrote:

As far as the automotive engine is concerned knocking generally will not cause any damage to an engine. However, if real severe and done over a prolonged period of time it can.

How long a period of time do you think it takes? A month, a year? I'll tell you. It takes less than seconds for the effects of detonation to show up in an engine.

Where does it show up you ask? The first place is always in the bearings, particularly the big end rod bearings. When the pressure spike that is created from the irregular combustion forces the piston downward, it has to go somewhere. It doesn't magically open up a hole in the piston. It forces the con rod against the crank jornal. The bearings fail at the top of the upper bearing shell. When you disassemble the engine you can tell by looking at them if the engine was detonated or not. You can also mic the bearing across the width to see if there is a fatter section.

The piston that Otto has, was consistently detonated, over a long period of time. Detonation builds up heat. With the added pressure spikes, and heat, detonation abraids the aluminum of the piston top away. Notice how the piston looks like an over done roast? Its because this engine was detonated over a longer period of time without being severe enough to cause problems right away. When detonatioon is severe, you typically see ring problems and major bottom end trouble before the piston lands on the ground. Note, ring problems create piston problems.

Grease, no matter what the octane, doesn't help. Unless your gonna pack the bearings of your bicycle while your car is in the shop.

Later

 

[Rick Stafford]

Please remember people that the fact that also leads to this problem is that fuel that sits around LOOSES it's octane value !!!! So buy good gas and use it and just pay a little more for your fuel and get 89 or better and use a certified oil that meets jaso FC and ISO L-EGD REQUIRMENTS. There are now more 2-stroke manufactures meeting these standards and I know that echo and husky XP oils do and I think shindiawa made the grade as well.

 

[WRW]

Tundraotto,
I've never heard pinging in a two-stroke engine. Can you describe it? Is it like the ping in an automobile or more of a ringing noise?
As for the Suzuki piston, was that a 4-stroke?

 

[Rick Stafford]

You won't hear it !!! It's just a discription that we can relate with !! I guess it's described as combustion before ignition !

 

[WRW]

OK, then how would you know that it's pinging when cold but not when it's hot. This is an honest question...I've heard what i took to be a relaxed clutch spring allowing the shoe to impact the clutch drum giving a ringing sound. If you can't hear pinging, I may have been correct.

 

[HUSKYMAN]

A fitting end to our monthly discussion of oil.

 

[Fish]

Well Otto hears pinging!

 

[tundraotto]

well thank you all regulars (you know who you are ) for your once again uninformative comments indicative of your absentmindedness of the issue...

pinging is heard very clearly by people who dont need a hearing aid - its called "pinging" for a reason. if you cant hear pinging when its happening - you dont need to get anywhere close to any motors.

 

[Fish]

I was guessing the pinging was from the piston
hitting the long reach splitfire plug.
Fish

 

[eyolf]

Here's an interesting discussion on oils from a small oil company...http://www.goa-northcoastoil.com/tips/2cycleol.html.

This company sells a synthetic oil meeting the Jaso and L-egd standards by the quart, gallon, or tanker truck, I suppose, as well as the little bottles, and it also packages it with the fuel stabilizer, at least in the little bottles.

For about the past 5 years, I have been using Rotax oils from the Ski-doo dealer; I got the stuff really cheap on a sort of fire sale. I'm probably lucky not to have frozen any of my saws up on the stuff. I'm using the northcoast stuff now.

I got interested in the Northcoast oil when the local gas station had their bar oil for 1.39 a gallon, limit one. Turns out I could buy all I wanted for about $2 for a while...Northcoast was giving it away to draw attention to their products. Seemed Ok to me; bright red, not much sticky and pretty thin, but seems to work as well as the Husky oil I been using in my Jonsereds saws.

 

[Cicero]

Otto, you are right most of the information given here has been at best mindless guesses.

Harley,

Please do some homework before you make us read anymore long, misinformed opinions on engine performance and wear. My information is not all my own. I listen to those who really do know the answers to the questions asked and merely pass that info on. If you consult the Technicians Manual Changes in Gasoline III, turn to page 4, look at paragraph 2 it says:

"The actual loss of power and damage to an automobile engine, due to knocking, is generally not significant unless intensity becomes severe. Heavy and prolonged knocking, however, may cause damage to an engine."

Advisory Board Members include Thomas Bridge the Chairperson of Engineering Technology at Western Illinois Univ., Bruce Perreault Automotive Technology Instructor, ect. ect. ect.

Since you now have revealed to us the extreme extent of damage that pinging can do to an engine, I can confidently write the Advisory board and Technical Committe of this worthless publication telling them Harley says your wrong.

Or you can call 1-800-378-9974 and for $2.50 get your copy and save us the trouble (I'll throw in the first buck). Now granted this a 5-year old publication...Maybe things have changed.

 

[Cicero]

P.S. High octane grease???? Will be backordered for months due to its overwhelming popularity. Please consult www.poopyjoe.com for you advanced order.

sorry for the inconvenience.

 

[Harley]

Sorry for being long winded.

How many engines do you think the good Thomas Bridge has taken apart? How many hours has he spent making pulls on a dyno?

I guess the reason why all the cars manufactured in the last ten years have knock sensors is to ward off flying saucers

Just so you know where I come from. I worked for a company called RPM, a Ford authorized engine remanufacturer, located in Pennsauken, New Jersey. While I was there, I spent over 400 hours making dyno pulls. I know what detonation does, not because I read, or dreamed about it, but because I witnessed its effects first hand. I've ruined more parts than I can remember.

Try looking in an SAE publication.

 

[HUSKYMAN]

I guess the reason why all the cars manufactured in the last ten years have knock sensors is to ward off flying saucers

 

[Cicero]

co-written by a fellow named Allen Kasperson

He is the Coordinator of Toyata Techinical Education and Network & GM satellite Training. Only for the Lake Area Techinical Institute.

Maybe you are right, I just gotta go with the publication which was formulated from over 170 studies and reports. For what it may be worth I recieved this little gem at the Briggs and Stratton workshop I traveled to in Milwaukee...Maybe there is something wrong with me for travelling so far from home just to learn about lawnmower engines..they evidently thought it was credible.

 

[tony marks]

u guys may not know it, but u really slinging out an education
in 2cycle motors.as far as who is right ,dont matter to me since pogress depends on opposition in all things. philosopher mode turned off. later now