Engine break-in

[derelict]

Hi All

(sorry for my bad english.. as i'm coming from switzerland.... i just like this forum most ! :-) )

first of all... i want to thank everybody in this forum for their support i was getting during my first trex 600 built just by reading all the posts and the videos of finless.

i'm quite new to rc helis and during the last few months i had to learn a lot about gyro settings, pitch curves and all involved in rc helis... but there is still one big question in my mind:

how to start, breakin, tune and keep free of overflooding an align engine and/or the os 50 engine.

i've read and searched a lot of forums and articles related to engine management but got all kind of different information :-( ... so therefore... i would like to start this thread and hopefully turn it into the "ultimate engine handling" thread! ;-)

ok... lets first start with my current problem... and my questions involved... after that i (or others) can continue asking questions and contributing answers ;-)

ok.. well then..

the situation:
- new t-trex 600
- temperatures arround 26 Fahrenheit
- 15% nitro gas
- align os 50 engine
- mixture screw factory set (exactly in the middle)
- needle valve at arround 2 turns and a few clicks out of completly closed
- os 8 glowplug
- the servo idle position is just a hair of the mark on the engine case

my problem and questions:
- how should i start a new engine correctly ? .. i'm asking this.. because whenever i start the engine... it gets flooded very quick... .. if i manage to get it running... it'll die shortly.. without moving the throtle stick in any direction!! i've tried starting the engine for about 7 days... while having it running only ONCE !!.... after a few tries i had it all flooded and a lot of fuel in the exhaust pipe ( i had to unmount the pipe in order to release the massive fuel) !...... so you might say... hey... you are running way to rich... but are 2 turns at the needle valve and the mixture screw at center way to rich in the winter or even summer time ? or am i doing something terribly wrong ??

- how should i breakin the engine during the winter compared to summer time ?

- should i use os A3 glow plugs during the winter time ? or how does the whole glow plug story relate to all those other parameters (like outside temp, gas used, needle settings and so on) ??

ok... i think these are enough questions for now ;-).... i would like to thank everyone contributing to this thread in advance... and wish all of you a merry christmas !

Cheers

Marcel

[B-ONE]

Two turns is too much, a ringed engine needs to come up to temperature for the ring to seat properly. Try 1 1/2 or even 1 1/4 turns and check cranckcase temp. If you have a governor, turn it off. Hover and vary the throttle occasionally. Just land, check the bottom of your crankcase with the engine idling and make sure the temp is not too hot that you cannot keep your finger on it for about 6 secs or so. Do this for about 5 tanks of fuel. No two engines are alike. One will run well with 1 turn another with 1 1/8, etc...D

[derelict]

Try 1 1/2 or even 1 1/4 turns and check cranckcase temp
i've read about the finger test at the crankcase... but this is where my problems start... some say 3 turns... most say 2 turns... you say 1 1/2 .... this is getting me quiet confused with which setting i should start break-in. another thing is the mixture screw... which seems to affect idling mostly... so my engine good flooded while idling... so shouldn't i first concentrate on the idling screw? secondly... isn't the mixture supposed to be richer during the winter ?

thanks for you help and information

marcel

[invertmast]

i believe the OS manual calls for 1 and 1/2 turn out on the main needle valve and to NOT move the idle needle valve until the engine is running. 2 turns is way to much. The reason your flooding the engine is b/c you are cranking it over alot w/o any combustion happening, so the raw fuel is collecting in the exhaust and then eventually draining back into the cyldiner.

you also mention your throttle valve is "slightly" off from the low throttle tick point on the carb. i believe this is your problem, you have to little air going thru the engine to support running.

put a few clicks of positive throttle trim to get the carb body mark about 1/32 to 1/16" past the low throttle point. and turn your needle out 1 1/2 turns. try this and tell us what your get.

[BarracudaHockey]

Depends on the fuel, 2 turns is a good starting point though. More nitro means a richer setting is required.

The OS Manual says 1.5 turns open from normal which would be 3 turns, way too much.

[dna001]

Depends on the fuel, 2 turns is a good starting point though. More nitro means a richer setting is required.

The OS Manual says 1.5 turns open from normal which would be 3 turns, way too much.

Sorry to poke my nose in but how do you get 3 turns from 1.5....do you mean 3 half turns!

[BarracudaHockey]

The books says 1.5 turns open from normal. Normal is about 1.5 turns. 1.5 turns plus 1.5 turns = 3 turns

I think thats way too much, two turns is rich, depending on the fuel it could be rich or burbling rich.


B-ONE is right on, it needs to warm up to break in and you may well end up at 1.5 turns or less to get it to smooth out and warm up the back plate but it's always best to start on the safe side.

[vteknical]

Hey Marcel,

B-One and Invermast are correct. I broke my o.s in at 1.5, it was pissing oil out the exhaust even at that setting after 5 flights it settled in at 1.25 to 1.0 depending on temperature. Now I use a Carbsmart and those worries are over.

Run your first tank at 1.5 and click 1-2 leaner every tank thereafter for 3-5 tanks. After the third or fifth tank start tuning it for performance. Since you mentioned you are new to nitros you may need the help of an experienced nitro pilot with tuning at first, especially with temperatures in the 20's.

Above all, start building a Pre-flight routine, this is extremely important (from a safety perspective)for a complete nitro newbie.

Perhaps a laminated 3X5 card. This should be taylor to your Heli and equipment used.

Refueling

Startup

Post Flight

Victot

[derelict]

okay.... i've tried 2 turns out from fully closed... again... i'm using 15% nitro fuel.... the mixture screw was at the center..... but still.... i had no "ignition"... and after a while the engine (and the muffler) was flooded.... i very rarely had the engine running for a few seconds... but then it died again.

this is driving me crazy... and i begin to just accept, that it's not a good idea to try to start and break-in a new engine in the winter!!

i've checked the glowplug and even replaced it with an A3 glowplug which seems to better fit the temperature i have in my country at the moment (26 Fahrenheit or -3 Celsius) but still no luck, a flooded engine and a lost faith in my engine! :-(

is anyone running or recommending the A3 glowplug for winter ? what is different to start an engine in the winter ??

secondly.... as i came back home pi****ed off... i thought i'll check out the engine for any leakage or stuff like that... and guess what... i had a lot of rust on the crankshaft and finally after disassembling the whole engine... i had to realize that my inner bearing got corroded/rusty... the same way as finless is telling about in his post http://www.helifreak.com/showthread.php?t=40622

This is a NEW engine... which was never running more than one tank while idling !!

so i guess i have to replace those bearings first....anyway... could that relate to my starting and "running to rich" problem somehow ?

just as a side note... i allways take my heli out of my flat into the car... once i'm arrived at the flying site... i put it out of the car and let it get to temperature for about 15min (26 Fahrenheit) BEFORE my first attempt to start the engine!

Any help and information is very much appreciated !

marcel

[derelict]

B-One and Invermast are correct. I broke my o.s in at 1.5, it was pissing oil out the exhaust even at that setting after 5 flights it settled in at 1.25 to 1.0 depending on temperature. Now I use a Carbsmart and those worries are over.

Run your first tank at 1.5 and click 1-2 leaner every tank thereafter for 3-5 tanks. After the third or fifth tank start tuning it for performance. Since you mentioned you are new to nitros you may need the help of an experienced nitro pilot with tuning at first, especially with temperatures in the 20's.



Thank you very much for your information! i "basically" know how to start nitro's as i have an airskipper which is running fine for about three months (allthough it was broken-in in september ;-) )

i'll try 1.5 turn the next time... and the tip about the carbsmart was very intersting as well... it sounds like you are having a good experience with it.. right ?

is there anything special to start an engine in the 20's (sorry.. i have nobody which is experienced enough... i'm on my own with this one :-( )

anyway... if you read my previous post... i start to believe to just leave everything as is... fix my bearings... and start the break-in in spring as i can't seem to manage starting the engine in winter.

thanks

marcel

[vteknical]

Carb smart is working great. I've only flown when it's been 30f or higher.
Temperature is not the cause of your starting issues. You are flooding the engine is all.

Here what you need to do to get er going.

Pinch the incoming fuel line to the carb................Remove the glow plug..................turn the engine over with your started shaft to get fuel out of the engine, three five second shots should do it....................Put the glow plug back in.....................Start the engine using your normal procedures, note keep the fuel line pinch closed for now......................you should get it to at least run for a second or two.......................now un pitch the line and start it up.

Alway keep the fuel line pinched shut when the heli is not being used.

[invertmast]

You need three things to get combustion:

Fuel
Air
Source of Combustion

w/o one of those nothing happens.

according to your posts you have 2 of the 3 things. AIR being the one you do NOT have.
From your first post you said "the servo idle position is just a hair of the mark on the engine case"

I just looked at my 600N w/ the throttle at idle and my carb body mark is about 3-5mm past the low throttle setting on the body...

Move your trim up enough to put the mark in that proximity and see what happens.

I also suggest putting the OS#8 plug back in the engine instead of the A3. the A3 is intended for sport flying and lower power making engines. Its not designed for the abuse of heli engines, but will work, but not as well as a #8.

[derelict]

@vteknical:

ok... i'll try it this way next time... thanks

@invertmast:

it really makes sense what you are saying! i just remembered the time as i was starting my airskipper at the beginning where i had to open the throttle stick for about 1/4 of the whole travel range in order to get the engine running. once it was running for one tank idling was fine at the stick at its normal position.

i'll try it with more throttle and the #8 plug next time (but first i have to replace my corroded bearings :-( ).

But isn't the amount of fuel increased as well the more i open the throttle, causing the engine to be flooded even faster?

secondly... according to: http://www.osengines.com/accys/choosing-glowplugs.html they say: "Guideline 5: The hotter the day, the colder the plug." .... therefore i thought i'll put a hotter plug in... because the day is quiet cold at the moment ;-)... so i can't be that wrong... does it ?

thank you very much for your valuable information!

greets

marcel

[invertmast]

@vteknical:

ok... i'll try it this way next time... thanks

@invertmast:

it really makes sense what you are saying! i just remembered the time as i was starting my airskipper at the beginning where i had to open the throttle stick for about 1/4 of the whole travel range in order to get the engine running. once it was running for one tank idling was fine at the stick at its normal position.

i'll try it with more throttle and the #8 plug next time (but first i have to replace my corroded bearings :-( ).

But isn't the amount of fuel increased as well the more i open the throttle, causing the engine to be flooded even faster?

secondly... according to: http://www.osengines.com/accys/choosing-glowplugs.html they say: "Guideline 5: The hotter the day, the colder the plug." .... therefore i thought i'll put a hotter plug in... because the day is quiet cold at the moment ;-)... so i can't be that wrong... does it ?

thank you very much for your valuable information!

greets

marcel



The A3 plus is a colder heat range plug i believe. I"m using the #8 OS plug in 22f+ weather w/o any issues and have been for a long time.

you will be putting more fuel into the engine, but you'll be putting more air in as well, which i feel is why your engine isn't starting (not enough air). And b/c your not getting any airflow thru the engine right now, its creating alot of suction pulling alot of fuel into the engine flooding it quickly.

[BarracudaHockey]

15 percent fuel probably will be closer 1.5 turns running ok moving closer to a turn out when its broken in. Some people start with 30 percent where a richer needle would be appropriate.

[nikpro]

Just try 11/2 turns on the needle valve and also move the mixture setting screw slightly clockwise so it is also leaner. Move the throttle trim up a couple of clicks and just get the engine idling first.

As long as you don't try to get the heli off the ground on the first tank you will be able to check the backplate tempreature and see if it is ok.

(this worked for me in -1deg c)

I was very careful running the (2nd) engine in as I had put a hole in the first piston - needle was 1 turn open and 2 clicks but believe I had an air leak in the cylinder head as the bolts were loose on inspection!

[derelict]

@invertmast:

According to http://www.osengines.com/accys/glowplugs.html the A3 Plugs are hotter than the #8 plugs. i've just rebuilt and replaced the bearings in that engine.... but 'm still curious in break-in and running the engine at the current temperatures due to the failures i had before..... i'll give the "more throttle" thing a try next time.

@BarracudaHockey:

so let me get this right... the more nitro you use... the richer the needle valve.. right ?

@nikpro:

the mixture screw was factory set to a little bit off the center towards the richer side (counter clockwise)... so should i move to the center or off the center towards the lean side ?

Thanks to everybody for the tips !

Greets Marcel

[BarracudaHockey]

Yes, more nitro needs a richer needle.

http://www.raptortechnique.com has two great articles on engine tuning, well worth reading.

There are a lot of things that effect engine tuning. As as been touched on nitro and glow plugs, also the type of muffler has a large effect depending on its back pressure and expansion volume, the nitro AND oil precentage of the fuel, the blades and pitch/throttle curves, gearing, weather, density altitude etc all effect engine tuning to some minor or major extent so when someone says "my hyper purrs like a kitten at 1.5 turns" means nothing more than thats what works for them with thier setup and location, you need to find what works best for you, and the safe way to do that is starting on the slightly (not slobbering) rich side and working your way to your final setting.

[Steelie]

Derelict,
I'm also new to helis. I also have a new 600N just finished. I also tried several times to start the engine and flooded it every time. Sometimes without starting at all. If it did start, it would idle fine for a couple minutes then run rough. If I tried to throttle up, it stopped. Very frustrating indeed.
However, I am not new to glow engines. I have been flying planes for 40 years off and on. My instincts told me that too much fuel was flowing into the engine but I tried to stick to what the guys are saying here. I avoided turning the low needle. My mistake. After seeing what Finless said to do in a different thread, I turned the low needle in to about the 1:30 position. Runs fantastic with the high speed needle at 1.5 turns out. After acouple more tanks, I'll turn the high speed needle in a tad for better power. I was just a bit hesitant to make an adjustment to an upright engine against what the manual suggested. I knew only horizontal engine habbits, or at least I thought.

What is happening, at least in my case, the low needle was factory set to a position where all engines like it 'should' run. However, sometimes an adjustment is necessary even if new. Not all engines that come off the assembly line are exact clones. With an overly rich setting, the fuel collects in the crankcase while idling. When the throttle is opened to whatever degree, the air rushing in tosses the excess fuel into the combustion chamber and extinguishes the plug as it cannot handle such a wet mixture. Try pinching the fuel line momentarily after startup. This will spend some of the collected fuel and then make throttleup happen easier. Don't be surprised if you too may need to turn the low needle in a tad.
One other thought. The fuel in the tank, when full, is higher than the needle on the carb. This condition causes a siphoning effect and promotes flooding. Use the fuel line 'Pinch Clamps' to control this.
This was my two cents. If I'm wrong, I'm sure we will all hear about it.:lol:

[nikpro]

I have the mixture screw set to approx 2 o'clock (lean side from center) and the needle 11/4 turns out (engine broken in.

Just try main needle at 11/2 turns and mixture screw at 2'o'clock (lean side of center). If you just bring the rotor up to speed and don't take off for your first tank you can check temps and ensure engine is ok.

[derelict]

okay... thanks to everyone for their tips.... i think i start again (i've just rebuilt the engine with new bearings) with the mixture screw at arround 1:00 for breakin... and arround 1.75 turns on the main needle.... i'll try to start the engine with the throttle stick at about 1/4 (which makes it arround 2-4mm away from the 0 throttle mark at the engine case).... i'll start with a half filled tank and try to manage the amount of fuel going to the engine by pinching the fuel line.

does that sound okay for my next wishfull tries ? :-)

secondly... i'm still concerned about the temperatures as i've just realized my bearings got rusty and corroded on a new align engine.

is there anything you guys do in order to get the heli back into a warm place after being out in the cold, in order to avoid rust and condensation water from building up in the engine ?

Thanks again

marcel

[nikpro]

Marcel; 1.75 turns on main needle will be too rich, trust me - start at 1.5 turns but don't take the heli off on the first half tank. Let the rotor build up to speed then lower it back to idle - keep repeating this for the first half tank then check the engine tempreature.

Don't put your throttle stick at a 1/4; just start with the stick in it's lowest position and the trim centred then give the trim 2-3 clicks to open it a touch further.

[derelict]

this is more or less the way i tried to start my engine (1.5 turns out / 2 clicks at the throttle stick) but i always flooded the engine! i even tried 1.25 turns just to see if i can start the engine!

cheers

marcel

[fishtank]

Hi Marcel

I am from Germany living on the schwäbische Alb. We have the same temperature as you have. Yesterday it was between -2 to +2 Degree Celsius. I tried to start the engine of my Caliber and i had the same problems like you have. I filled my engine with fuel because he didn´t want to start. I have the advantage of a building near the position where i am flying. I did put the heli on a table to clean the Engine. I have a kind of industrial blower which makes a nice temperature about 22 degree celsius. in the meantime the heli got warm. After the cleaning i tried to start the heli with open gate of the lodge so if he starts i can take him outside to fly. the blower´s direction was in the direction of the heli and the warm air helped to start the engine.
It was funny but he started right with the factory settings. Besides it´s a GX36H from Kyosho. Maybe it´s not a good comparison to the OS 50 but this was my experience with the temperature. After the flight i tried to reconstruct the problem and left the heli for 10min outside get him cold. It didn´t start although i made him leaner. After the warm air in the direction of the carburetor there was no problem with starting the engine. Maybe it´s too cold for the kyosho engine. I hope next week i´ll get my T-rex 600 nitro kit with os 50 Hyper and after build up i can report you my experience with the os 50 and the cold weather that we have around here.
By the way i love the waves my heli is doing with the snow
Looks like scale :-)

[derelict]

thanks for sharing your experience with temperatures we have here in europe ;-)... it's nice to see that others having the same issues like i do.... but you engine is not brand new like mine... right ?... i'm just thinking about to NOT let the heli get to the outside temperatures and just start it right out of the car! but still i have to manage to get the heli back to a warm place somehow... without causing any condensation water and/or corrosion inside the engine bearings!

i'll give my two birds (t-rex 600 and airskipper 60) a next try next week myself.. hopefully we can share our experience with a new os 50 break-in in winter next week as well ;-)

Greets

Marcel