RE: Breaking-In a sideways oriented engine
 

Turk
If you had mounted that VW in a test stand and followed the referanced breakin procedure that probably would not have happened... :D
Seriously, I have run a lot of the flat 4 cylinder engines and have never seen that happen.. Never had it happen with my Mag's or Saito's either...
Interesting

RE: Breaking-In a sideways oriented engine
 

No need to start trouble like that.

RE: Breaking-In a sideways oriented engine
 

My turn to be a wise guy...

All ya gotta do is fly upside down for half a tank each tine you fly...that'll balance out the wear, huh!?:eek::D

RE: Breaking-In a sideways oriented engine
 

Finaly a solution that makes sense :D

RE: Breaking-In a sideways oriented engine
 

Whats the matter, this is what we're all about. Take a perfectly good thread, change the subject and then beat it to death! :D Everythng is fine.

RE: Breaking-In a sideways oriented engine
 

Oh, oh!

The piston is about to fall out of the side of this Lycoming O-320 cylinder, after gravity has worn the cylinders...

This won't happen on the AEIO-320... the aerobatics will even out the wear to the top side of the cylinders...


:D:D;);):):)[>:]

RE: Breaking-In a sideways oriented engine
 

I think that the cooling effect causing the front of the cylinder to be cooler causes the cylinder to be egg shaped while running. I would think this a much larger facter. Never miked a model engine bore, but liquid cooled auto engines engines were sometimes worn one thousandths or so wider side to side. This is not enough to be a factor either way. So once again we have a bunch of nuts (engine nuts) arguing about much of nothing.[:-][sm=spinnyeyes.gif]

RE: Breaking-In a sideways oriented engine
 

Hey it is winter, raining etc... Can't fly... No need to get so serious :D

RE: Breaking-In a sideways oriented engine
 

Hugh,


This is a result of rod angularity.

As the piston descends the rod around the crankshaft, to one side, so as a result, the piston is pushed against the cylinder bore to the other side.

No extra force is applied to the piston ring(s) from the rod angularity, but only to the piston itself.

If you are behind an engine that spins clock-wise; the counter-clock-wise cylinder wall will suffer more wear.
In an in-line engine, that would be the left cylinder wall(s).

RE: Breaking-In a sideways oriented engine
 

Did I say I didn't know why? My point is that the wear is insignificant. One thousanths of an inch on a four inch bore is like 0.00025 of an inch on a one inch bore. It has even cooling so it doesn't wear front to back as many aircooled foward shaft engines do. Both is rather insignificant. Why don't we argue about something that matters?

RE: Breaking-In a sideways oriented engine
 

I would think the average RC engine is not around long enough to worry about it

RE: Breaking-In a sideways oriented engine
 

Hugh,


Who's arguing?

I just pointed this out, so some of the people that don't know, will.

RE: Breaking-In a sideways oriented engine
 

Sorry, thought you thought that I was mistaking the wear from uneven cooling with wear from desaxed or normal wrist pin movement. All are rather insignificant.

RE: Breaking-In a sideways oriented engine
 

I had to replace a Tecumseh 10 hp engine because of uneven wearing. The engine was nothing but trouble. Not a model engine, but still an air cooled 2 stroke.

RE: Breaking-In a sideways oriented engine
 

Was that an aluminum bored engine? If so they don't last if overheated. The high silicon aluminum softens or loses its silicon grains or somthing can't remember. When that happens then it will wear out quickly and unevenly . That's a four stroke engine BTW.

RE: Breaking-In a sideways oriented engine
 

I owned a Tecumseh engine some 20 years ago. It was a four-stroke, 3.5 HP.
My gardener has one powering his lawn-mower that runs on the same fuel-oil mix as the edge trimmer and the hedger... It is a two-stroke.

So they have both types...

Isn't all this way off subject?

RE: Breaking-In a sideways oriented engine
 

Whenever I pull an engine (model engine ) apart for bearings, or whatever, I inspect the sleeve closely with a jewlers loupe.
I have often noticed uneven wear around the sleeve, especially at the top where the pinch is. It seems that on most of my engines, there is a larger area that is "polished" by the piston at the rear of the sleeve?

I would have thought that the cooler front of the sleeve would wear more?

Either way, uneven wear is caused by uneven temp. distribution, among other factors, aye?

RE: Breaking-In a sideways oriented engine
 

PropTop,


When a cylindrical object heats and expands non-uniformly, it remains close to a perfect circle.

The expansion difference is that the original 50% of the circumference that has heated more intensely, has now become a bit more than 50% of the circumference. There is no reason for there to be any uneven wear.

Oriented?? Isn't the word 'orientated'?

...There appear to be photos in this message that I have not added, nor can I remove, or edit out.

Will a moderator help take the photos out?

....>>>>Some kinda' weird glitch here, they won't go away. FBD.

RE: Breaking-In a sideways oriented engine
 

Not exactly sure what you're trying to say there Dar?

Anyway...just telling it like I see it...(what's that called...empirical data? Real world experience? )

BTW, all I see is pictures of little red X's?

RE: Breaking-In a sideways oriented engine
 

RE: Breaking-In a sideways oriented engine
 

Yep, it was a 4 stroke.

RE: Breaking-In a sideways oriented engine
 

Is that like almost pregnant? Close only counts in horseshoes and hand grenades.

The extra polishing of the sleeve at the rear is more likely due to the cylinder leaning forward. The engine guy that told me about this effect machined his engine cases with the cylinder tilted rearward cold so that it would be in the correct position when at operating temperature.

RE: Breaking-In a sideways oriented engine
 

Godzilla,


Monarchs are usually self appointed.:D;)
They do not need anyone to die and 'leave them in charge'... They just are.;)

I don't see, in the title of this thread, the words 'Anything you like', or any other similar clause.

While I often did contribute my own 'off subject' posts, to threads that have already gone 'off subject'; according to RCU guidelines, such threads are discontinued.
It was a hint to the moderators that this thread has gone its course and should be closed to new posts.

---------------------------

You have just joined this forum and you started off 'on the wrong foot', by taking the side of the wrong in a heated, scientifically oriented debate, intentionally misspelling my name. ...and doing it as impolitely, as impertinently and as personally as possible.

People who have started their term in RCU, by intentionally 'ticking off' existing members, have not reached tenure...


I believe you should 'restart' in a more agreeable manner.

RE: Breaking-In a sideways oriented engine
 

They have a 10 HP two stroke? I don't think so.

RE: Breaking-In a sideways oriented engine
 

That depends on your definition of "close". I understand it is enough to cause motorcycle v twin engines to wear slightly oval. Again this depends on the definition of "slightly".