RunRyder RC
 13  Topic Subscribe
WATCH
 4 pages [ <<    <     2      3     ( 4 )    >    >> ] 5284 views
HelicopterEngines Plugs Mufflers Fuel › Another one bites the dust !!!
01-23-2007 11:00 PM  10 years agoPost 61
rotor- shark

rrVeteran

uk

My Posts: All  Forum  Topic

well we can go on forever with this,but i can tell you that you will not be able to run the os as rich as you will be able to run the west, the piston and liner fit does make a difference at running speed.the best way to run any engine is to run it as rich as you can but without loosing any power in the process.that way you have maximum cooling.the os 70 is not too difficult to tune(when it's not cutting out on spool up)but you can't tune it all that rich.best bet is 30% fuel.i can tell you this much about an engine,i learned to be able to tell what condition an engines piston and liner was in just by watching it hover.if theres not a great deal of smoke,and the pilot has tuned it to it's best running setting,then the compression is not all that high.on the other hand,if the smoke is unbearable,creating a dense fog that takes ages to clear,then you know the compression is pretty good.obviously the fuel type has a big impact on this.use 30% and the smoke increases dramatically,also thin oil types such as cool power lv oil will do this,so it must be a like for like comparison,and the carb must be sensibly tuned for reasonable power.anyway i think the thread has been dragged too far from it's original purpose so i'll retire now.regards.

all comments are my opinion only!

PM  EMAIL  Attn:RR  Quote
01-23-2007 11:50 PM  10 years agoPost 62
StillTryin

rrApprentice

Perth, Western Australia

My Posts: All  Forum  Topic

Rotor-shark - don't quit now. I'd miss your alternate understanding of the workings of a 2str glow engine.

You state "i learned to be able to tell what condition an engines piston and liner was in just by watching it hover.if theres not a great deal of smoke,and the pilot has tuned it to it's best running setting,then the compression is not all that high.on the other hand,if the smoke is unbearable,creating a dense fog that takes ages to clear,then you know the compression is pretty good."

Would you expand on this concept a little. It certainly is a new one from my perspective.

PM  EMAIL  Attn:RR  Quote
01-24-2007 10:00 PM  10 years agoPost 63
rotor- shark

rrVeteran

uk

My Posts: All  Forum  Topic

ok well.............bear in mind that the amount of fuel in the chamber at combustion has a bearing on how much smoke will be present at the exhaust,taking into account the fuel type and nitro as mentioned.if the engine has a great deal of compression,then if too much fuel is present,ie too rich setting,the engine will still fire during the two stroke cycle as normal.the extra fuel going through the engine will help cooling a great deal.on the other hand,if the engine has very low compression(basically a worn out engine)then if the carb is tuned to the same rich setting,there will not be enough compression to fire it to the same degree of power and some of it will be spat out of the exhaust as raw fuel,this will show itself as a rich blubbery running condition,with limited power,usually the helicopter will only hover when it's this bad.when the engine is like this,the solution to get it to run is to lean the mixture setting to a level that the engines compression can deal with,this will make it run,but the smoke level will be noticably down due to the lean setting,compared to the other good engine with the same fuel.the temperature will also rise due to the lack of fuel going through the engine.this is why a worn out engine seems to over heat all the time,there is not much combustion going on,burnt oil residue takes away a lot of the heat from an engine,in the good engine there is plenty of burnt oil to take away heat,in the poor engine there is not as much burnt oil residue,and that is not taking away the heat as well.

this you will see,is the reason a person can roughly tell that an engine is in very good shape by the dense fog the exhaust is creating,too much fuel is easily being combusted.on the other hand a person can see that the engine is in poor shape due to limited smoke,too much fuel can't be easily handled,so the engine has had to be severely leaned to get acceptable running,and this is causing limited smoke.now common sense will reveal that you can actually tune the good engine badly,and cause very low smoke to be produced,so this type of visual clue to an engine is only any good if you have tuned the engine yourself,and know that you have the best available setting.a begginer will often tune the engine wrong,even though the correct setting is actually available on his or her engine.

hope this has gone some way to explaining this for you,i will now retire(again)and get back to running my steam traction engine!(in my gallery)regards

all comments are my opinion only!

PM  EMAIL  Attn:RR  Quote
01-25-2007 12:31 AM  10 years agoPost 64
supertigre

rrApprentice

Castle Rock, Colorado

My Posts: All  Forum  Topic

Gads, what a bunch of hooey. I would love to give you a bunch of different engines to run and have you tell me whether they were worn out by the amount of smoke!

I GUARANTEE that you cannot tell the condition of an engine based only on the amount of smoke. There are just too many variables.

Paul Mcintosh
Owner-CRCustom.com - custom vinyl lettering, banners, signs

PM  EMAIL  Attn:RR  Quote
WATCH
 4 pages [ <<    <     2      3     ( 4 )    >    >> ] 5284 views
HelicopterEngines Plugs Mufflers Fuel › Another one bites the dust !!!
 Print TOPIC  Make Suggestion 

 13  Topic Subscribe

Thursday, December 14 - 2:09 am - Copyright © 2000-2017 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online