OS 105 HZ R needles

[CyprusFlyer]

Synergy N7 clutch repaired and flew today, heart sank when I ended up with a closed main valve and running rich
Sooo, whipped out that 91HZ main needle assy and fitted, started at 3 turns out
Ran rich and hey, my temperature is nearly 90 Deg Centigrade so landed and leaned out a bit, wow, she is singing now, my governed head speeds are bang on at 1800 and 1950 according to the spektrum telemetry , have not seen that before or more correctly heard the difference when switching IU1-2, still looks rich.
So got down to 2.5 turns and had a temp alarm via telemetry at 115 Deg C so landed.
Ended up at 2.75 (900ft elevation) slightly rich, head temp around 100 Deg C and gentle manoeuvres at 1800 head spead, a few punch outs, mid I left at 0.5 turn out, looking OK. I was also confident to do a few flips and big sky stuff so thats good.

I had to lean out the idle about 10 deg for reliability as it cut out a few times, cured it.
My Carb Smart servo is not mechanically connected yet but noticed that moving to regulate so in the ball park now.

I know I have a duff regulator from new, that sucks and I am not going to waste time with OS or sending the whole engine back to my dealer that was suggested! I have another regulator coming slow time so will try and revert, if that fails then the 91HZ needle is staying!

BTW Lots of power wow! No bogging at 13 deg pitch, nice.

[Rodney Kirstine]

Nice! Our weather has been crap so and I haven't torn into mine yet to try and figure out what's going on with it. Mine is also running rich with the high speed needle closed.

It's crazy how much power the 105 makes, even when it's running way too rich!

[rctintin]

Great thread, lots of info here.

Glad you got flying Cyprus, more that me at the mo!! We are having wind and rain in epic proportions here in the UK, so my N7 is just sat looking pretty, along with my brand new Synergy E7se, and Thunder Tiger E700 all un-flown!!

[Rodney Kirstine]

Originally Posted by rctintin

Great thread, lots of info here.

Glad you got flying Cyprus, more that me at the mo!! We are having wind and rain in epic proportions here in the UK, so my N7 is just sat looking pretty, along with my brand new Synergy E7se, and Thunder Tiger E700 all un-flown!!

Oh man, that's rough.

[CyprusFlyer]

We are watching the UK weather news from Cyprus, it looks like Armageddon over there, glad we moved over here at the moment, ironically they are bleating about water shortages here, send a bit this way
New regulator has been on its way from the USA for a week or so, will try with stock once it arrives, prove it once and for all. It is partially working, does shut off and holds tank pressure indefinitely but obviously too much fuel getting through once it opens.

Nothing like a bit of tinkering, I missed that from planks to be honest. The electric heli's are like a Mechano kit then its plug and play in most cases. Nitro its nice to do a bit of fiddling about and thinking.

BTW fuel I use at the moment is Rapicon 15% Nitro and 20% oil, didnt have the heli mix so looks like it is flying around on green fairy washing up liquid lol.

Alun

[rctintin]

Well I'm happy to report the weather gods were kind to us today in the UK!! First nice day for a few months, so I managed to maiden the Synergy N7 this afternoon

I got 6 tanks through her, and have started to lean out the OS105 HZ-R a touch, and thankfully it looks like I have a good one!! She was super smooth, never missed a beat, and lots of power even nice and rich.

As for the N7..... Awesomness it not big enough for it!! What a heli!!

[CyprusFlyer]

Nice one, great heli indeed Nitro is great and love the smoke trial doing huge loops, like a red arrow lol.
Had about the same yesterday too, nice and sunny, still waiting for another regulator, couldn't get consistent with the mid setting, all bets on because there is too much fuel pressure getting through, be good to get it working as intended.
All making sense now, had to lean the idle and mid no where near recommended, soon have it sorted, 91HZ needle letting me play for now though.

[CyprusFlyer]

A bit more saga relative to this thread in Misleading manual post #15

[Sirolf]

I got to fly again today after a 5 week break and started to tune my 91HZR
a bit further since it got a new piston and ring. Low and behold...high needle fully closed
and still running rich.

I have a 91HZ carb in my spares box. Is the main needle a direct swap and a must to do
to be able to tune this thing?

I recently did a pre-maintenance on the regulator and cleaned it well so i don't think
it's stuck open.

[dchekas]

Originally Posted by Sirolf

I got to fly again today after a 5 week break and started to tune my 91HZR
a bit further since it got a new piston and ring. Low and behold...high needle fully closed
and still running rich.

I have a 91HZ carb in my spares box. Is the main needle a direct swap and a must to do
to be able to tune this thing?

I recently did a pre-maintenance on the regulator and cleaned it well so i don't think
it's stuck open.

Changing to the 91HZ main needle is not the answer.

The 91HZ-R, 1.05HZ-R, and Speed 3D have all been out for several years now. There's something else going on here.

I have a brand new 1.05HZ-R fresh from Tower Hobbies. I've got about 6 flights on it, but my needles *look* like they're going to settle into the expected band: 3/4-1.25 turns out on the high running 22.5% with the single thick shim in the head.

Something is up if the engines are running with the high completely closed....

[Steve Graham]

^
I tend to agree. Sucks when things like this happen. It can drive you to distraction. Makes the sweet moment when you figure it out all that much better.

[CyprusFlyer]

Yes it sucks and agree something is going on, although swapping for a HZ main needle seat did give me a useable engine that actually ran lean enough to achieve the target head speed and get to normal operating temperature. Still persevering and waiting for a mixture control valve and throttle barrel to compare with what I already have, after that I have no more ideas, have to ask where the hell is OS in all this, not isolated incidents, quite a few with this problem. BTW Definately not the regulator, I have compared 3 and the vacuum force required to open the valve is the same on all/
Otherwise I have a YS Tareq 91 on the way from JapanRC may swap this out if there is no resolution soon.

[Sirolf]

Originally Posted by dchekas

Changing to the 91HZ main needle is not the answer.

The 91HZ-R, 1.05HZ-R, and Speed 3D have all been out for several years now. There's something else going on here.

I have a brand new 1.05HZ-R fresh from Tower Hobbies. I've got about 6 flights on it, but my needles *look* like they're going to settle into the expected band: 3/4-1.25 turns out on the high running 22.5% with the single thick shim in the head.

Something is up if the engines are running with the high completely closed....

I deliberately left the pressure on the tank overnight with the fuelclamp opened.
Still had decent pressure when i vented the tank just now so that tells me the
regulator closes just fine.

If using the 91 needle makes the engine run leaner why not go down that road?
And what if the spring which pushes against the diaphragm is to weak?

[dchekas]

Can you guys measure the diameter of the hole through the middle of the main needle seat?

It's the first picture in post #5 from this thread: https://www.helifreak.com/showthread.php?t=515164

[Gscott]

Has anyone tried different tube lengths to the one way valve? I know from first hand experience that running a shorter fuel line to the one way will over pressurize the tank which will force more fuel through the regulator at a given needle setting. I doubt that it is a design issue with the needles. There are too many of these engines out there that are working as designed.

[dchekas]

Originally Posted by Sirolf

I deliberately left the pressure on the tank overnight with the fuelclamp opened.
Still had decent pressure when i vented the tank just now so that tells me the
regulator closes just fine.

If using the 91 needle makes the engine run leaner why not go down that road?
And what if the spring which pushes against the diaphragm is to weak?

Changing to the 91HZ needle seat is simply masking the issue, not solving it.

If it was the spring, it would likely be isolated to a single regulator.

[dchekas]

Originally Posted by CyprusFlyer

Yes it sucks and agree something is going on, although swapping for a HZ main needle seat did give me a useable engine that actually ran lean enough to achieve the target head speed and get to normal operating temperature. Still persevering and waiting for a mixture control valve and throttle barrel to compare with what I already have, after that I have no more ideas, have to ask where the hell is OS in all this, not isolated incidents, quite a few with this problem. BTW Definately not the regulator, I have compared 3 and the vacuum force required to open the valve is the same on all/
Otherwise I have a YS Tareq 91 on the way from JapanRC may swap this out if there is no resolution soon.

Cyprus, you've installed each of those 3 regulators on the engine and tried running them, correct?

[CyprusFlyer]

Yes thats correct absolutely no difference in needle settings, runs rich. In my humble opinion its pointing to an incorrect orifice, ie main jet in the venturi is oversize or maybe the relationship between the throttle barrel and mixture control. Ideally I would need to compare those two parts with the HZ (91 or 105 carbs).
In another thread I also posted how I tested them by sucking through a pen barrel, its quite easy to assess the correct operation of the regulator that way.
Some success using the 91HZ needle seat about 2.75 turns gets the high end fairly well tuned but the mid then becomes super critical to tune.
Another give away is that the idle also has to be leaned quite a bit for a reliable idle.
So too much fuel getting through, plenty of pressure that holds well, regulator is fairly well ruled out, so again, whats left....size of the orifice in the mixture control function of the carb.

[CyprusFlyer]

Originally Posted by Gscott

Has anyone tried different tube lengths to the one way valve? I know from first hand experience that running a shorter fuel line to the one way will over pressurize the tank which will force more fuel through the regulator at a given needle setting. I doubt that it is a design issue with the needles. There are too many of these engines out there that are working as designed.

Good point and 10cm is quoted in a few manuals, cannot see a significant pressure difference if within plus minus a cm or so. Mine checked at 10cm.

[Gscott]

Have you tried lengthening it to reduce the tank pressure? I would try 15-20cm to see if it makes a difference.