OS105 HZR running rich, both needles all the way in

[datatools]

Hi guys, I see another post regarding this issue, but wanted to start another to deal with this issue specifically. My new OS 105 HZR is running very rich, and I'm now at the point where BOTH the mid and high needle are screwed all the way in. I leaned the idle mixture a bit, and it idles great. After a 5 minute hard flight, I land and hold my finger in the bottom plate and it feels cool. I'm thinking about switching to the 60M carb and getting rid of the regulator. Does anyone know what might cause this rich issue, and if the OS60M carb will fit on the 105HZR engine. Thanks.

[dodgeboy]

Sounds like something could be holding the regulator wide open. But im not sure.

[datatools]

Something else I can add, this is NOT an easy engine to get started. I have to crank it over 20 or more times before it begins to fire. Once its running it runs good, but way to rich. I'm not impressed since its a brand new engine, and all my other OS engines run great. Any ideas?

[Rodney Kirstine]

Are you sure your idle mixture isn't still too rich? Did you use the pinch test to set the idle mixture? My 105 fires right up. I hardly have to crank it, at all, and I was also able to tune it to the point where it was lean. At least for me, the key was getting the idle mixture set correctly before tuning the two needles.

[datatools]

When it does start up, it settles into a nice low idle right away. I did lean the idle mixture screw a bit (maybe 5 degrees from factory), but I'm afraid to go to far. How many degrees did you end up leaning your idle screw?

To start this engine, I have to crank it over lots, but once started it runs good! Once I get it started, I can shut it down immediately and restart with hardly any effort at all. So My guess is something in the regulator is causing issues.

[Rodney Kirstine]

This is from the tuning guide that I used:

http://www.jupiter-venlo.nl/Algemeen...0EN%20v3.1.pdf

The link is in this post in the stickies:

https://www.helifreak.com/showthread.php?t=111007

Pinch Test
The pinch test is the First method to tune your Idle Setting:
1. Hover the helicopter for 30 (somewhat) seconds
2. Land it and drop the RPM to idle
3. Pinch the fuel line closed just before the carburetor (where the fuel line is connected to
the engine) and start counting the seconds
4. The engine should rev up and die because of lack of fuel.
5. If this is between 3 and 5 seconds its all right
a. Sooner? Too lean
Turn the Mixture control screw richer for 10 degrees counter-clockwise
b. Longer then 5 seconds? Too rich
Turn the Mixture control screw leaner for 10 degrees clockwise
6. Return to step 1 until you got it right

[marc8090]

The hard to start situation except after an immediate shutdown is no fault of the engine, but unfortunately user error. The regulated engines can be nearly impossible to start if not properly primed, and fire up instantly when correctly primed. What you need to do if the engine has been sitting for a while is crank it over WITHOUT lighting the glow plug. You will need to experiment with throttle position, as I've found different engines prefer different amounts of throttle. Some prime well at idle, some half open, some full open. Find whatever throttle position primes the engine well. It's usually about half throttle, so, at half throttle crank the engine over until you see fuel flow from the tank to the carb. Once you see this, continue cranking for a few more seconds until you hear an increase in rpm. Stop cranking, throttle to idle, light the plug, crank it over and it should fire right up.

[itbvolks]

To add to this - I just fired up my 105 yesterday.

What I've found is - you can crank that sucker forever without drawing any fuel to the reg. Just doesn't open the reg enough to pull any real vac.

What I do is plug my pipe with a finger and crank it quick. It'll pull fuel to the reg very quickly. Add spark and mine fired right up. Once it's primed - you can land and refuel and it'll relight nearly instantly.

This is running rotor rage 22.5% on an OS8. Even pig rich - it idled without issue and cleanly cleared out on spool and flew great.

[datatools]

I tried all the tricks with my 105, but it still cranks forever before firing up. I finally changed out the regulator on the carb for the standard fuel inlet, and now the engne will fire right up and tuning is not an issue. I would have liked to make the regulator version work, so perhaps I'll try again down the road.

[CyprusFlyer]

Well I have the 105 and 55 HZ-R, both a real PITA, both I have switched to muffler pressure and replaced the regulator with the fuel inlet ring and normal main valve seat.
Now they both start really easy, are easy to tune, run consistently and I just enjoy flying instead of tinkering constantly, almost as easy as electric now!
Carbs are slightly different so settings a bit different to the HZ recommended but find lean and back off a bit, still works as expected, says it all in my opinion

[msallua]

Originally Posted by Rodney Kirstine

Are you sure your idle mixture isn't still too rich? Did you use the pinch test to set the idle mixture? My 105 fires right up. I hardly have to crank it, at all, and I was also able to tune it to the point where it was lean. At least for me, the key was getting the idle mixture set correctly before tuning the two needles.

I'm new to nitro, How i perform the "pinch test" to set the idle mixture ?
Thanks

[Rodney Kirstine]

Here is one of the tuning guides I used when I first started with nitro engines.

https://www.google.com/url?sa=t&sour...0ERCCqOjCEgVrw

The information is also in one of my previous posts earlier in this thread.

[Lighty]

There is an issue with the needle valve holder on the 105hzr. (high needle)

[Rodney Kirstine]

Originally Posted by Lighty

There is an issue with the needle valve holder on the 105hzr. (high needle)

An easy way to check is to screw the high speed needle all the way out. If you can slide a 1.5mm Allen wrench into the orifice, it's too large. The correct one has a smaller diameter. I'm believe they took care of this issue about a year ago.

[msallua]

Originally Posted by Rodney Kirstine

An easy way to check is to screw the high speed needle all the way out. If you can slide a 1.5mm Allen wrench into the orifice, it's too large. The correct one has a smaller diameter. I'm believe they took care of this issue about a year ago.

Thank for the advice, I bought 2 months ago my OS105 in RCJAPAN.NET, perhaps the issue has been solved in my engine, I check later (the orifice) with a 1.5mm before the maiden.

Many thanks!

[msallua]

Originally Posted by Rodney Kirstine

Here is one of the tuning guides I used when I first started with nitro engines.

https://www.google.com/url?sa=t&sour...0ERCCqOjCEgVrw

The information is also in one of my previous posts earlier in this thread.

Ok, Excellent the tunning guides ( my engine is OS105 -> 3 needle )

It's time to tunning my engine. Maiden perfect. a lot of smoke.

Coolpower 30%
2x shim of 0.2mm in the head
Sea level in my country.
In this moment , high needle 1 turn open, middle needle 1.5 turn open

I read the document several times and I fully understand , never active the governor during tunning.

But

It does not say what type of throttle curves must I set to make the adjustment correctly.


Thanks

[dchekas]

1 turn out on the main needle with the new needle seat described above is too lean IMO.

I would richen to 2.5 turns for break in. The mid needle at 1.5 turns is fine.

[msallua]

Ok, , I have the correct needle seat. ( checked last night )..

The break-in was made the last weekend . aprox. 5-6 tanks ... with the main needle with 2.5 turn out and 1.5 turn out.

I read and watched many videos and tutorial. They said first begin to close the main needle

From 7 flight , I began to close the main needle .. A lot of smoke and the temperature is OK in the engine . I can touch the backplate for ever . After some sport flying ( loops, rolls, tic-toc )

[msallua]

Originally Posted by Rodney Kirstine

This is from the tuning guide that I used:

http://www.jupiter-venlo.nl/Algemeen...0EN%20v3.1.pdf

The link is in this post in the stickies:

https://www.helifreak.com/showthread.php?t=111007

Ok, The guide is good and recommend don't use the governor for tuning.

What type of throttle curve do you use to tuning the high needle and med needle ?

thanks in advance

[msallua]

[QUOTE=Rodney Kirstine;5836872]This is from the tuning guide that I used:

http://www.jupiter-venlo.nl/Algemeen...0EN%20v3.1.pdf

Ok, The guide is good and recommend don't use the governor for tuning.

What type of throttle curve do you use to tuning the high needle and med needle ?

thanks in advance