OS Hyper 50 Performance

[hduk]

Hey All,

My OS50 Hyper seems to have developed a strange issue and i cant seem to get to the bottom of it.

From new it has always taken ages to start maybe a minute or so but once it fires is has been ok until recently.

I was doing a few bad flips and when pulling out on the last attempt it really bogged down. I thought that it may have been a mixture problem (currently on its 4th gallon cp 20% main is about 1 1/4 turns) until this point it had been fine no issues whatsoever. I turned the needle out but im still getting the same issue. It also only seems to do it when inverted. Climbing out the right way up is fine.

Ive checked the clunk and whether inverted or right way up it doesn't snag and it reaches the bottom of the tank. Ive changed the plug, set mix to 1 1/2 turns, pitch range is +/-10, but still have same issue, im stuck. Any suggestions? Or pointers?

I was tempted to replumb the whole thing but visually it looks fine, not sure whether its worth stripping the engine to take a look? Or im i completely of the mark with the mix, maybe headloaders worth a go?

Any pointers appreciated.

[trillian]

What pipe do you have on it?

I found that some Align pipes can retain fuel and it can then be sucked back into the engine when trying to start it. This was the problem I was having. I suppose it's possible that the same pipe issue could affect it in flight as well sometimes.

[hduk]

Forgot to mention that, its the Align one. Must admit that hadn't crossed my mind. I know i had a simular setup on a 600 sport and that always used to flood before starting. Wonder if its worth changing it? Only thing is its only recently started to play up, do they build up residue inside that could cause the symptom?

[trillian]

Forgot to mention that, its the Align one. Must admit that hadn't crossed my mind. I know i had a simular setup on a 600 sport and that always used to flood before starting. Wonder if its worth changing it? Only thing is its only recently started to play up, do they build up residue inside that could cause the symptom?

Well I had a real mystery with mine for a while because sometimes it was fine and then sometimes it would act hydrolocked and I would take out the glow plug and drain out any fuel and then it would imediately do it again and I tried everything I could think of. I finally changed to an MP2 pipe and have never had that kind of problem again.

It was when I removed the Align pipe and found lots of fuel still in it, even though I had tilted it at all angles and the fuel did not run out the back. So somehow it was trapping fuel up by the manifold where it could go back into the engine. You could probably avoid the starting issue by tilting the heli over when starting. Lots of people have no problems with the Align pipe so it doesn't always happen.

[Si_B]

I would definitely re plumb the system. Takes another factor out of the equation. Might be worth checking the carb and filter are clear.

[synergyn9]

check you haven't got a split in your clunk line which is allowing the engine to suck air when inverted

I would replace all your plumbing as a starting pointing

[hduk]

Thanks for the pointers so far chaps, will take all the points here and report my findings. Any comments on my needle settings as a starting point?

[chugga-bug]

Mine used to run nicely at 1 turn on 30%, so if you're running 20% I'd expect it to be a bit less than 1 turn out. Mixture screw should be left as is, or just a fraction leaner.

[hduk]

In that case do you think i could just be way toooo rich at 1 1/4 - 1 1/2?

[chugga-bug]

Most likely, yes.

[gazelle341]

main is about 1 1/4 turns) until this point it had been fine no issues whatsoever.

If it has been running fine with no issues then this setting should be ok and does not suddenly need altering - something else has caused a change. As already suggested check or preferably replace all the lines, particularly the clunk line.
May also be worth removing the carb inlet nipple and checking there is no build up of crud.


Cheers
Mick

[Trickyr6]

Well I had a real mystery with mine for a while because sometimes it was fine and then sometimes it would act hydrolocked and I would take out the glow plug and drain out any fuel and then it would imediately do it again and I tried everything I could think of. I finally changed to an MP2 pipe and have never had that kind of problem again.

It was when I removed the Align pipe and found lots of fuel still in it, even though I had tilted it at all angles and the fuel did not run out the back. So somehow it was trapping fuel up by the manifold where it could go back into the engine. You could probably avoid the starting issue by tilting the heli over when starting. Lots of people have no problems with the Align pipe so it doesn't always happen.

Mine has been doing the same thing feeling like it's hydrolocked for no apparent reason, even if it hasn't had chance to get flooded.
I am running the Align pipe, so will check to see if there is fuel still in there. Thanks.

[Janek]

Check your starter battery. . . . . . . might be something that simple

Saw a case of this at the weekend

[chugga-bug]

Maybe, as a result of running too rich, the oil is not getting burnt away and building up in the pipe. If it was running leaner (hotter exhaust gases) the oil wouldn't collect in the pipe.

[Trickyr6]

Just checked pipe and there is no fuel or oil in there, so could just be a weak battery.