lack of oil, or me

[GunnyGlow]

Look at it this way...

If you have been running glow engines for 50 years and this is the first time it has happened....you are rather fortunate.

©DROID/Tapatalk2™

[rcflier1]

lets try this. the high needle is factory set at 1 turn open, and the range is 1/2 to 1 1/2 turns. i,m almost 3 turns and having the problems. and the pump/tank pressure is fine.so you see why im stumped

[Kneedragger75]

Originally Posted by rcflier1

lets try this. the high needle is factory set at 1 turn open, and the range is 1/2 to 1 1/2 turns. i,m almost 3 turns and having the problems. and the pump/tank pressure is fine.so you see why im stumped

Something else is wrong. The pump/tank pressure is fine, are you just guessing?
You have to see how frustrating these threads are. You asked a question about oil,
got advise from several posters advising to look elsewhere. You still say it's oil.

I am not sure which engine we are even talking about. Diagnosing tuning issues
second hand is quite difficult. You don't seem to willing to listen.

[seanh]

sounds like an air leak. First thing I'd do is replace all lines and fittings. If your tank has been in a crash, it possibly can have a crack.

Could be junk in the carb.

Are you sure your muffler is properly sealed? They have a tendency to loosen a bit.

Maybe the head isn't sealed and is sucking air?

[rcflier1]

i did check all the tank fittings and changed the lines anyway.the tank has lots of pressure, as it should with a ys.if i pull the line off the engine, the fuel shoots out a bench.i guess i,m just upset that i wiped 2 engines in a week.i am going to switch to a fuel with more oil as a try, anyway. i will rebuild both engines and try again.

[flyinfool]

OK, shot in the dark here, Do you run a fuel magnet? If so how old is it. I know they are not supposed to be an issue for YS since there is or at least should be no exhaust in the tank.
But when the go they plug up the carb causing a lean run.

Look at you jug of fuel to see if there is crud on the bottom of the jug, I have seen bran new not even opened bottles of fuel (from several manufacturers) with stuff floating around. Do you have a fuel filter? Do you have a filter in the line between the fuel pump and the end of the line for filling your tank?

[ahahn]

Originally Posted by rcflier1

well, why than it starts and idels fine.hovers fine and flys about 3 min ok with what seams like pleanty of smoke, than all of a sudden it sounds like it's getting hot.think i,ll give up and stick with electrics.i can't believe a 5% change would require 3-4 turns more open!

You have said this a couple of times now.

Yes in absolute terms, this is 5% more nitro, compared to the remaining alcohol and oil. However in terms of nitro, you are running 33% more nitro than before.

Nitro is an oxygenator. In other words it provides more oxygen to the combustion process. That's why you need to richen the mixture. With that extra oxygen, if you did nothing, the burning would be on the lean side.

Also one typically might want to add an extra head shim for higher nitro fuels. However your engines may (probably are) setup for at least this much nitro in the first place.


However you did open the needle. I am believing, as others that you may have a gummed-up fuel system, that is giving you a lean run even after opening the needle.

[rcflier1]

last thing and than no more. it's after the fact, but now i wonder if the govener was not doing it's thing properly and i has an overspeed condition. yes i have the book curves in, but in stunt that does go to 100% at the endpoints. i was banging the left stick before the failure

[seanh]

Check valve issue? Don't know much about YS engines but have heard something about check-valves getting stuck. Is it possible that the valve could have crud in it allowing pressure on one side but low pressure fuel on the other?

Just a thought since we really don't know at this point.

[hpcc]

Now that you mentioned over revving might be possible, it could have made your engine run hotter than its designed running temp, causing pre ignition and melted a piston but I'm still inclined on lack of fuel (either some hardware is malfunctioning or tuning was off). The reason behind my belief is that over revving usually ends up with a broken connecting rod. Someone was right in pointing out that maybe a pressure problem is a possible cause. To verify if your tank is pressurized, run the engine at hover rpm for a time and throttle down. upon removing the pressure line on the tank, a quick but powerful hiss should be emitted.

I know for a fact that Wildcat Heli-mix has one of the best oil contents. When I was starting out with nitros before (with cars though) I noticed that bearings usually rust out when after run oil wasn't used (ATF). Fast forward to Nov last year when I came back to Nitro R/Cs but this time with helis, I was initially using a different brand of 15 % and didn't have the time to put ATF on the engines. Lo and behold bearings produced a weird sound and upon inspection, they were rusted and ended up with a premature bearing replacement. A friend then suggested that I tried Wildcat. Immediately I noticed that something was weird with this fuel. It smoked alot less but was spewing out oil on the muffler and the frames were oily as well. Up to now, when I inspect my bearings I don't see any signs of rust or even unexpected wear for that matter even without using ATF.

I have been playing with Wildcat Heli-Mix for my YS-56SR and YS-91SRS in both 15 and 30% forms. Needle settings only vary from 1/4 of a turn to roughly 3/4 max on switching nitro content. The only thing that I would say my old fuel was better at was power (though by only a very very small margin). But I heard the premium, more expensive mixes are alot more powerful than their basic heli-mix ones.

Just be patient and one by one remove the variables, you'll get your answer.

[rcflier1]

ok, thanks. and yes, pulling the line gets the hiss as pressure in the tank releases

[hpcc]

may I ask what glow plug were you using on both?

[rcflier1]

os#8

[Magooch]

I had a force .26 that was in an Ofna violator that ran around 300 deg when it was new. I had to add a shim to that motor to bring temp down. If I remember right it did not take much. I also used to have a mip on board temp gauge on this buggie. Do you guys use these on heli's? Is there room to hit the head with an ir temp gauge? How do you monitor your temps? I have not seen a modern day nitro heli in person yet.

[hpcc]

well that seems right, as that's my plug too both for 15 and 30 percent.

hope you find the culprit and don't give up!

[rcflier1]

may eat a little crow here, but reading a lot of posts thuout hf. i realized i never broke them in right. 2 or 2 hover flights and that it was off flying. i started blasting around probably way too soon and thats the reason for the overheat/failure.i,m used to electric heli's and i was board sitting in one spot more or less.

[Velislide]

I dont know if anyone mentioned it, but running a higher oil mixture in your fuel with a 2 stroke will cause the engine to run lean, your burning less fuel then you are air. The fuel cools the piston, and oil lubricates the rings and crank bearings. I dont know a lot about nitro motors, but if switching from say 15% to 20% fuel, I'm guessing thats the lubricant content in the fuel, you'd be burning less fuel, and would cause it to run leaner.

[desertstalker]

Originally Posted by Velislide

I dont know if anyone mentioned it, but running a higher oil mixture in your fuel with a 2 stroke will cause the engine to run lean, your burning less fuel then you are air. The fuel cools the piston, and oil lubricates the rings and crank bearings. I dont know a lot about nitro motors, but if switching from say 15% to 20% fuel, I'm guessing thats the lubricant content in the fuel, you'd be burning less fuel, and would cause it to run leaner.

Actually its the nitromethane content, thats an oxidiser, so makes the problem even worse. You have less fuel and even more oxygen than you had before...

[flyinfool]

It is common for higher nitro to also have higher oil contents.
This gives you a leaning effect from the oxygen in the higher nitro AND a leaning due to a smaller amount of fuel due to the higher oil content. When you change fuel, open those needle valves up.
There are different thoughts on breaking in a engine. there is more than 1 right way to do it. Pick one of the methods from someone you trust and follow it. Ignore all other info. Combining parts of different methods can destroy things if you do not know what you are doing. I've been told that I do everything wrong, but I am still running a Hyper 50 from the very first batch that ever came to the USA.

[rcflier1]

yea, this issue is only with my ys's. my hyper 50 is just fine.i just blew it somewhere along the line