600/OS55 Cutting Inverted

[coolice]

Squeaky's flying exactly how I used to as well, 3D without a governor and using curves alone, nice :-) I remember John Parker being surprised when I met him for the first time and 3D'd with no governor.

The comment on his engine being a little lumpyish on idle is perhaps a good point, going from what I mentioned earlier with the 50 Hyper liking a thicker low end needle. Having said this I'm not sure if I'm reading the 55 has a 3 needle carb, does it? I've not played with one to know.
.

[electricsceadu]

you are correct in thinking that theos55 has a 3 needle carb

[squeaky pete]

i havent used a gov for about a year now my n9 never had one, nor does either of my ely qs lol and yes, i went for a slightly rich idle purely cos thats the best way to get the power out a 50, thought its might be the same on the 55 works for me

[coolice]

i havent used a gov for about a year now my n9 never had one, nor does either of my ely qs lol and yes, i went for a slightly rich idle purely cos thats the best way to get the power out a 50, thought its might be the same on the 55 works for me

Hey.

Cool, I never used to myself until I wanted to try set rpm's on various blades to see year suited my models best for F3C. It can be done eh just takes a little longer.

Sorry buddy are you running a 50 Hyper? Defiantly like yourself with these I found you need to run a richer idle to stop the nitro pop in the hover, which is just a lean point and predetonation in the pipe.
Now its confirmed its a 3 needle carb in the 55 it should be easier to tune out a mid range fueling problem, set low to get a reliable idle, set top for power, reset low if need be then adjust mid needle to richer it up as needed. Sounds simple enough but I remember older 91 three needle carbs sometimes being a right pain!
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[squeaky pete]

I'm running a 55, but tuned it how's I used to tune a 50, slightly rich on idle

[rachel]

Ian I don't know if it's getting worse just seems to be since I started to lean it in.

You forgot to put it in idle up again didn't you ?


only kidding I just remembered I had a very similar thing once,
I had swapped fuels in Rexy (700 le os91hz 3 needle carb)

On take off I usually do a forward flip to invirted climb and then fly backwards towards myself, on this occasion I did that as I got to invirted and pulled the pitch back (unloading the motor) it just stopped
No leaning or ritchening instantenious cut out

Some how I pulled off a really lucky auto just damaged the tail blades (phew)
what got me was how it cut out just dead no loading , warning, or any symptoms at all.

two clicks ritched on the mid needle and it hasn't happened since.

Just for info OS No8 plug Csm Revlock 20 , Optifuel 20 (not slv) matching underwear lucky pilot

sorry for you crash

's XXXX Rachel

[Geek]

Have you blown a few plugs laterly?

If so it's too lean

[sacko]

Bearing changed recently? If its at the end of its life it maybe going lean.

Stick your needles at around 1.5 turns out, and that should give you a pretty good start. Do you know what they are on now?

[waveydavey]

Have you blown a few plugs laterly?

If so it's too lean

No, changed it 2 weekends ago and it shows no signs of being either lean or rich, just nice and clean.

[waveydavey]

Bearing changed recently? If its at the end of its life it maybe going lean.

Stick your needles at around 1.5 turns out, and that should give you a pretty good start. Do you know what they are on now?

The top needle was about 1.25 and I think the mid is about the same with the idle as set from the factory. It's had around 4.5 gallons through it since new and the bearings are fine.

[sacko]

You know anyone who could lend you a tuned engine? If you are coming down my way at any time, you're more than welcome to whip my engnine out and try that in the 600; should rule that out.

[waveydavey]

Cheers Paul a generous offer, thanks. It really points towards the tuning as everything else has been renewed, checked and double checked. I originally thought it was something to do with the clunk line I was using so changed this, renewed the tank, cleaned the carb out etc. I'll give the tuning a go this weekend and make sure I've got plenty of height this time, after I've rebuilt it of course.

There was a TT53 in prior to this and apart from the odd hiccup now and again it never cut out. Or my hyper for that matter.

[sacko]

1.25 wouldnt be rich on the OS55 though, and that is the only reason it would cut.

If it was lean (which would sound more likely and those needle settings), I would have thought you would have done some plugs. Did you mention it sounded lean in flight?

Have you checked the seal on the tank bung? The seal on the muffler? A light smear of epoxy is the best solution I have found so far.

[Nick B]

Could it be that crap fuel your using Dave LOL

Ive always ran a slightly rich medium speed needle on my 55,probably 5 clicks richer than the high.on opti the idle was at factory but since using bekra i have had to lean it ever so slightly but still slightly lumpy on the pick up

[squeaky pete]

oi!! im using the same fuel lol and i just checked again, to be more accurate, its abit more like 1 and 3/8ths on each needle, and the idle where i said, somewhere between 2 and 3 o clock, not lean at all, engine is still cool, leave your finger on it for ages, plently of smoke, loads and loads of power

dave we will get to the bottom of this coz im feeling responceable for your troubles now