RunRyder - Help. low zenoah 231 rpm on a second tank of fuel

rrTV-PHOTO

New HD TV

HOME rrTV-PHOTO GALLERIES MY GALLERY HELP-FAQ

myHOME PM pmRR MEMBERS 635 ONLINE 20 EVENTS SEARCH REGISTER START HERE

1 page

508 views

POST REPLY

XHELI.COM	.	Autography FlightPower	.	Advantage Hobby
	.		.

Gasser Model RC Helicopters > Help. low zenoah 231 rpm on a second tank of fuel

3manPL
Heliman
Location: Poland

I need some help. I have 3 jr ergo z230 gassers. i boutht all of these machines used some time ago. if i take any machine to the field the first tank of fuel everything is ok and smooth. flies like a beauty. when the fuel get's low i land it stop the engine and usually talka some time with other fliers before i tank it up and start flying again. so on the second tank of fuel it seems the engine can't reach proper rpm. at first tank i hover at a bit over half stick on the second tank the machine starts to hover at allmost full stick. itle up 1 is the same. if i just don't do anything but just hover i can hear the sound of my engine get a bit lower than higher. it's cyclic but not very fast. funny thing but i have the same problem with my other gasser. first tank ok the second problems with rpm. i can't find the cause. i don't think the engine is in a bad shape otherwise i would have problems like this all the time even on first tank of fuel. i thought i made incorrect mixture and just in case addes another measure of oil - so it was twice the usual amount. nothing changed - maybe just more smoke that's all
does anyone have a clue what can be the problem and the solution for it?
thx

08-01-2008 07:58 PM

Brunobl
Veteran
Location: Pomerode, SC, Brazil - 26 40S 49 11W

What changes from the first flight to the others? If you let the engine cool down completely (say for more than an hour) will it behave erratically too or will it be OK? Try to see if it is temperature-related. Maybe an air leak develops as the engine heats up?

Whatever it is, don't fly on too much oil. You may well get a piston ring stuck from the excess oil goo.

-------------------
Best regards,
Bruno.

08-02-2008 12:54 AM

GREYEAGLE
Key Veteran
Location: Sioux City IA

Wonder ?

Wonder if all three helo's are on the same radio, all three with the same pitch and throttle curves, over pitched ??? under throttle curved

greyeagle

08-02-2008 03:29 AM

3manPL
Heliman
Location: Poland

hello Brunobl and GreyEagle, thanx for replying.
well. it looked like this - i did fly machine for one tank of fuel - about 25 minutes not a single problem with the engine. running smooth all the time. arter that i had about 20 minutes rest then i filled the tank again and tried to fly. it did fly but i could hear the engine had lower rpm and it sometimes dropped a bit down even though i was just hovering and did not move the sticks at the moment. it did hover at allmost full stick. seemed to me like the engine did not have the power to lift off. it finally did but after a few minutes i just gave up i did not want to crash. a few months ago i had a similar problem with another machine same type. first tank of fuel no problem whatsoever on the second tank when my buddy flied it it just died out about 7m above ground. didn't have much time to do anything and he had a hard landing. bent flybar, broken blade, bent one pushrod and i beliebe bent mainshaft. after looking at the wreck i came to a conclusion that it could be the fault of the spark cap. on that particular machine it was made of metal with a spring. it was all broken so i guess maybe it just fell apart from the vibrations, no spark no engine. crash.

well on the machine i flew 2 days ago the spark cap is made of rubber it sits in place very well so i don't think this is the problem. i was out of town yesterday will try to fly it this evening and will see if the situation will be the same, first tank ok and then problems .

i use the same radio for all of the machines but each one has sligthly different curves and setup, because of different blades and minimal differences in pushrods.

the third machine i did not fly yet. i just fired it up on the ground first without blades and everything seemed ok then i put on the blades and tried to lift it off but even at full throttle it just sat there. the pith and throttle curves seem ok. double checked blade angles. with the blades on the engine works erratically rpm rises and lowers. i have put on a brand new carb on it. changed the gasket.
nothing changed. i didn't take apart the engine yet - that is the last thing i wanna do but from the look at the piston it looks ok

any ideas?

the one heli i did not fly yet is the one here - http://www.runryder.com/helicopter/t393228p1/

thanx for any help

08-03-2008 12:01 PM

3manPL
Heliman
Location: Poland

Now that i don't understand at all. I just returned from the flying field. As i startded the engine cold it was working perfectly. A minute to warm up and i went on flying around without any smallest problem. engine was working perfectly, so after 10 minutes of flight i landed my heli and turned it off. I started it up after 5 minutes break without changing anything and the problems begun right away. the sound of the engine changed constantly higher/lower, it just did not want to fly. the helicopter was very light on its skids but it was like it had no power to fly. turned it off again. 5 minutes break and i start it up again. same problems but now it behaved more terrible, from time to time the servos "jumped" and even when the stick was allmost at zero it looked like it wanted to jump up and fly ( from time to time) the engine from time to time would pick up rpm very fast so i got a bit scared it would just jump up and crash. turned it off again. 10 minutes break and started it up again. i left the stick at zero so the engine was just idling for a few minutes. i wanted it to get really warm. yep this time i could fly although it wasn't 100% as the first flight. the helicopter felt sluggish. i just packed up and wen't home. it's a totall mistery to me. i thought i will try to change the rx tomorrow and see what happens.
any ideas?

08-03-2008 07:35 PM

pgkevet
Veteran
Location: surrey UK

..looking back on this thead I see someone has already suggested an air leak as it warmns up.
I had something similar on an old car.. cold it was fine, as it warmed up it died and then after a rest was OK.. finally tracked it down by luck to a small air leak by the carburettor which iced up until engine heat leached there enough to keep it from icing again..

A good tight plug with clean porcelain and good washers and swap out all your carb and exhaust gaskets for teflon and copper (if they aren't already).

..but don't take my word for it.. I'm literaly a 2 gallon expert on gassers.. see if anyone else agrees first

pgk

08-03-2008 07:56 PM

pphil611
Senior Heliman
Location: South Dakota

check your klunk line inside your fuel tank, sounds like you may have a kink or sharp bend in it.

Spectra-G, MAH, CSM

08-03-2008 09:23 PM

3manPL
Heliman
Location: Poland

thanx pgkevet and pphil611. i don't think its any of those.
if that was the case then problems would occur allready on the first tank of fuel during the flight. engine heats up and get's an airleak and problems begin. in my case problems begin after i make a first break in flying and kill the engine. it does not matter if it's after 5 minutes of flying or after the whole tank is gone ( about 25 minutes. during the first flight i can make all the evolutions i know how to make and it just flies great. when i kill the engine and make a 5 minute break in flying and then start it up again it's just not the same

08-03-2008 11:48 PM

GREYEAGLE
Key Veteran
Location: Sioux City IA

Sure sounds like the insulator block.

Remove the insolator, being careful, not to damage your gaskets and pay attention to the orientation of the little hole in the gasket and the block that provides crankcase pressure to pulsate the diaphram in the carb.

Optain a small piece of glass and some fine silicon carbide sandpaper 320 or 400 grit should do.

Place the paper on the glass with a few drops of oil and lap both sides of the phenolic block looking for the high or low spots to appear. Your goal is to remove the high spots intill the the color of the block is equal through out - as the low spots. Block it out gentley.

They useually appear around the holes where the bolts pass.

Reinstall and do not over tighten any fasteners that may deform the block. The plastic material is pretty dynamic - Firm is fine,

greyeagle

08-04-2008 01:42 AM

Excalibur
Veteran
Location: Destination: Earth

Ya know, I had a problem similar to this a year or so ago on my Predator. Just for the hell of it I changed out the throttle servo and the problem went away. I know this may be a long shot, but it's generally a quick and easy test to change out the servo. I kind of doubt it's the receiver. Good Luck.

Xcal

Camper Fuel: It's Not Just for Breakfast Anymore

08-04-2008 05:33 AM

3manPL
Heliman
Location: Poland

yeah i don't believe it's the receiver but actually nothing else comes to my mind. yep. i will try to change the servo then. i will also try to see that insulator block.
thanx everybody will tell you later if any of these helped

08-04-2008 09:22 AM

pgkevet
Veteran
Location: surrey UK

Quote
it does not matter if it's after 5 minutes of flying or after the whole tank is gone ( about 25 minutes. during the first flight i can make all the evolutions i know how to make and it just flies great. when i kill the engine and make a 5 minute break in flying and then start it up again it's just not the same

..as another thought from the newbie.. how about you're picking up an air bubble.. it's fine and sits still during first run and then when engine stops it shifts to a nuisance position and acts as a lock?

Change of clunk line, clunk and flush through fuel lines and the carb??

pgk

08-04-2008 09:53 AM

DRUMMER
Senior Heliman
Location: Dover, UK

hi,

I am not anything of an expert on gassers but could this be a tuning problem during breaking in? ie when cold running rich but a bit lumpy but when up to temp not enough power? or could the choke be slipping on as it used to on my zenoah?

One last stupid question to clarify things for me please, on the zenoah carb which is the high needle and which the low? I have the carb where both the neeedles are the same design but one is longer than the other....best clarify before i start fiddling!

08-04-2008 03:37 PM

HOMEPAGE

j.8
Senior Heliman
Location: Denmark

Hi Drummer

The low needle is the one nearest the engien

Do not use the settings on the picture, I have just
got my engien back from TRM, and they need to be reset

EDIT: Engien was in for a pump up, that`s why I`ll need
to reset the needles

Best regards Bo

08-04-2008 05:10 PM

shawmcky
Senior Heliman
Location: Isle of Wight,United Kingdom

Running problems

Sounds daft but have you tried leaning down the low needle(The one nearest the engine)Take it down to 0.75 or 3/4 turn out just to see if it makes a difference.Do this after your warm up.Has the weather been really hot when this occurs.Take your high needle to 1.25 at the same time.A really rich mixture will kill a hot engine as much as a weak one.I have had a similar problem on a hot day and the only way i could get power was to lean out the low needle.You have to be careful not to go too lean but its worth a try if you have not done so already.What is the colour of your plug after the first run?

08-04-2008 05:13 PM

shuttlepilot
Elite Veteran
Location: Mullins, South Carolina

I have also been thinking about this problem that you are having. Sounds strange but have you thought about the fuel boiling in the lines or the carb when it is hot. I know that usually an engine's temp will increase right after you shut it down, and if your fuel lines are near the crankcase or cylinder they could "boil" and induce a type of vaporlock situation.
I agree with the other comments about the carb insulator getting out of square with heat and that is first thing you should check....but if that is not the problem, and you are not getting air leaks anywhere else, then it is something to think about. It's a long shot, but a thought. I had this happen with one of my automobiles years ago.

Gas is Great
QWW Field Rep

08-04-2008 05:22 PM

3manPL
Heliman
Location: Poland

first check which carburator do you have. it's usually inprinted on the carb. like 167a or 213a. usually on these two carbs the needles are a bit different. the low needle is a short screw and high needle is much longer with a spring it's T shaped. here you will find a manual. Here you will find instructions how to tune these carbs. But first you gotta make sure its a gas carburator. Some time ago i bought w gasser which turned up was set up for nitro and it had a carburator for nitro. I just could not tune it up for gas, i just had to buy a proper one.

Well i thik i finally solved my problem!!!!! I fired up my bird today just outside my house to check up things and this time it went crazy just on the first start. rpm was quiet low then it would just jump up high. so i decided to tape the carb apart and to do things suggested by GreyEagle. while i was cleaning it a bit i noticed that the throttle arm has a slight slag on it's axis. it seemed the set screw wasn't holding it firmly. i took it all apart cleaned it, put it back together with some blue loctite. agter the rain stopped i took it outside again. i checked all the linkages end points and so on. had to redo my throttle and pitch curves. now it roars as a beast. the only problem i see now is hmmmm little flunctuations in rpm. as i hover without touching the stick the helicopter just slowly dances up and down about half a meter up and down from the hover position. must by something with the rpm yet as it gently drops down and climbs up. i guess i will have to check the needles yet to finetune it.
thanx all for help.

i guess that the other engine has an air leak - i checked it's throttle arm seems to be ok. will post any news probably after i get back from my holliday.

08-04-2008 05:30 PM

3manPL
Heliman
Location: Poland

just to inform you. the funny thing was that the throttle arm moved on it's axis but not freeley. the set screw must have been touching the shaft and the armo could move e vew degrees left and right but it got stuck at the ends. that's why i didn't see anything earlier. if it moved to the right position i could fly if it moved to the wrong position i just did'g get enough power because the throttle wasn't open in the right position. probably after landing when the engine was hot and the fan just wasn't cooling it the carb got a bit hotter then usual metal expanded and the arm would stop in the wrong position. i think that was all to it. waiting now for better weather and i hope i have a chance to fly it today

08-04-2008 05:37 PM

shuttlepilot
Elite Veteran
Location: Mullins, South Carolina

That's great, and makes perfect sense. Glad you got it sorted out.

Gas is Great
QWW Field Rep

08-04-2008 07:39 PM

3manPL
Heliman
Location: Poland

yep everything works fine first and second tank of fuel - flies great. lost my silencer in mid flight. second time. i think i will glue the bolts holding it with loctite although the engine head get's hot and i am not sure it will really work. i think silencers in x-cell craft are much better solved

08-04-2008 07:59 PM

1 page

508 views

POST REPLY

Revolution Models	.	CarbonXtreme	.	Midland Helicopters
	.		.

Gasser Model RC Helicopters > Help. low zenoah 231 rpm on a second tank of fuel

PRINT TOPIC

Advertisers

Subscribe to This Topic