r a

Essay only read if your not going to bollock me for grammar or spelling or
boring the tits of you :-)
I have two helix's both with engine problems one blew a hole in the piston
and has gone back to OS for repair. The other just keeps stopping without
warning, Its a OS 61 I have stripped the engine fit new bearing as they
where knackered, removed and cleaned out the fuel tank as the rubber grommet
had perished, stripped and cleaned carb, reset needles to factory settings,
fit new fuel piping. fit new OS 8 plug Engine started and ran fine,
fastened the heli on my workmate and fitted head loaders, engine ran fine
small adjustments to get the mixture so as to be able to run to full
throttle and back to tick over, all seemed fine, tonight refitted blades
took it out, got into a hover and the engine just cut again, didn't appear
too lean as it was smoking, but not excessive, engine restarted first touch
ran into a hover 10 maybe 15 seconds and stopped again running short of
ideas now, I was thinking fuel blockages but usually the helli would speed
up a bit and run weak before cutting out, but this just stops as though the
glow plug had failed. could it be running to rich as I scared to run to lean
in case I blow another engine, I'm using cool power fuel with 10% nitro not
old fuel. any thought would be appreciated.

Regards

Rob

the other kevin in san diego

How's the fuel system condition in general? Pressure tap plugged?
Clunk getting uncovered? Sounds like it's leaning out for some
reason, especially if you've burned up a piston.

Is the fan working properly in the helo?? How's the backing plate
temp when it quits? Can you touch it or is it blistering hot??

adrian smith

When you say it may be running rich. Do you mean, actually it's running way
rich. If so put it back on the bench and ahjust the needles to get the
optimun mixture as described in OS instructions. You can make the mixture
slightly rich to compensate for atmospherics etc once you know the correct
setting.

How old is the engine?

--
Adrian Smith
www.YourStadium.com
Superb aerial pictures of UK football stadiums.

r a

The engine is quite old I have owned the model for at least 14 years or so.
On the bench the engine ran sweet with the head loaders on. As I'm self
taught it hard to judge the smoke amount but as for videos and that I've
seen I would say it was normal. When I weaken the mixture the engine wont
tick over and is bad to start, when I richen it the engine wont rev at low
end but will run ok at high end and smoke a lot and when I try to go full
throttle it chokes a lot and then will pick up and rev up, when I believe I
have got the correct mixture right the engine runs well ticks over ok, if I
hit the stick to full throttle it revs up fine, no excessive smoke quite a
bit of thick oil comes out of the exhaust when its on the bench, When I put
the blades back on and take it out just as I'm in a low level hover all
seems ok but then the engine just cuts instant, doesn't seem to choke or run
badly just stops I have a beam type temp gauge and when it was on the bench
the engine was at 45 degrees but I didn't have it last night to know what
temp it was when it cut out. By the way it restarted instantly without that
dry binding you can get when its been to weak as well. thanks for your help.

Regards

Rob

funfly3

have you got the manual for your engine as tickover and full throttle are
two completely different settings???
I am new to helicopters but on all the planes engines I have had first you
adjust the full speed settings (ignoring the smoke as it does not tell you
to much) starting rich and leaning it out till it just stops sounding like a
four stroke and starts to peak then set the low speed for the best pick up
back to full speed

r a

I'm I right in thinking that the main jet is for full throttle setting i.e.
one and a half turns the manual recommends but it does not mention that its
for full throttle operation and that the other side of the carb the screw in
the middle of the throttle is to adjust the low end, a sort of fine tune ?

funfly3

http://www.littlerotors.com/articles...0103/index.asp
this might help

adrian smith

Rob

It could be that your engine is simply shagged.

Unless your good at autos I would buy a new engine and be done with it. An
engine that stops unpredictably is a liability. I only have OS engines and
they have all operated flawlessly. I think the only time I have had an
engine stop is due to lack of fuel.

--
Adrian Smith
www.YourStadium.com
Superb aerial pictures of UK football stadiums.

r a

Hi just to let you know I used the links suggested and I have now got the
engine running quite well, I was spending to much time changing the mixture
screw on the throttle linkage to try and get a reasonable hover, in turn
loosing tick over I was not paying enough attention to the main jet just
leaving it 1.5 turns out, I have now set the mixture screw for a good tick
over and then ran the engine into a hover and started to open the main jet 4
clicks at a time until I got a good response. I think all along my problem
has been running to weak. I also changed the plug from an OS8 to a enya 3

Rob

r a

Hi just to let you know I used the links suggested and I have now got the
engine running quite well, I was spending to much time changing the mixture
screw on the throttle linkage to try and get a reasonable hover, in turn
loosing tick over I was not paying enough attention to the main jet just
leaving it 1.5 turns out, I have now set the mixture screw for a good tick
over and then ran the engine into a hover and started to open the main jet 4
clicks at a time until I got a good response. I think all along my problem
has been running to weak. I also changed the plug from an OS8 to a enya 3

Rob