RunRyder RC
 4  Topic Subscribe
WATCH
 1 page 1648 views
HelicopterGasser Model RC HelicoptersOther › Gasser carb stuff
01-21-2013 02:18 PM  4 years agoPost 1
chris6414

rrApprentice

Sneads Ferry, NC USA

My Posts: All  Forum  Topic

Hello fellow gassers. I have done all the searches I could find and I think I have my issue figured out. I just wanted to run things by the experts. I have Century Predator with a broken in G23 PUH stock motor. She is running great at 1 1/8 on the LS needle and 1 3/8 on the HS. She climbs smooth on multiple climbouts.Full pitch is 9 degrees. Full throttle is set at 77 % as 100% and she starts really winding up near the top. Just flying scale anyway. 77% is stable HS from hover to full stick. Yesterday I was about half a tank and just flying some circuits and on approach coming down just below 1/4 stick on the collective and during the mild flare and adding some collective, she died on me. Thr Curve is set at 15% at point 2 and 13 on point one. Could it be loading up during the descent and flaming out? Or too lean on LS? I brought point 1 up to 15 as well to keep some throttle on those quick descents. I believe it is a tad lean on the LS but I ran out of daylight to test my theory. Engine RPMs are up, unloaded and then when I get back in the throttle there is not enough fuel to keep up with the RPMs. All new fuel lines and an MOAS clunk in the tank. Tank is tight under pressure test with no leaks. running 87 oct at 32:1. Thanks for any expert advice.

Century Hawk Sport, OS .32, Futaba 7C, GY-601 9251
Predator Gasser SE G-23, Fut 3010 servos, JR gyro/servo

PM  EMAIL  GALLERY  Attn:RR  Quote
01-21-2013 04:35 PM  4 years agoPost 2
rbort

rrProfessor

Franklin, MA - USA

My Posts: All  Forum  Topic

1 1/8

Seems rather low on the low needle. I would try to open then up some up to about 1 1/4 should be the sweet spot no more than that.

-=>Raja.

MA 1005 Hanson 280, 4142 flts
Spectra 27 3DMax, 3210 flts
Whiplash V1 Hanson 300, 1440 flts
Whiplash V2 Hanson 300, 207 flts

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-21-2013 05:08 PM  4 years agoPost 3
BeltFedBrowning

rrKey Veteran

Kansas City

My Posts: All  Forum  Topic

I set up Idle up 1 with higher throttle values so I can jam the throttle down for a quick descent without chopping the throttle. That is of course, if your not using a governor

PM  EMAIL  GALLERY  Attn:RR  Quote
01-21-2013 05:29 PM  4 years agoPost 4
Carey Shurley

rrElite Veteran

Orlando, FL - USA

My Posts: All  Forum  Topic

What is the model # of the carb? It can make a difference in the answer

If you're not flying a gasoline helicopter
You're paying 10 times too much for fuel!!

PM  EMAIL  GALLERY  Attn:RR  Quote
01-21-2013 05:37 PM  4 years agoPost 5
chris6414

rrApprentice

Sneads Ferry, NC USA

My Posts: All  Forum  Topic

Thanks Raja. It is a WT-643 carb. No governer. Lean is what I thought too. At 1 1/4 I get a burp every ten seconds or so at 25% throttle at the hover. Any more and she is 4 stroking and the tail is kicking pretty good and smoking a bit.

Century Hawk Sport, OS .32, Futaba 7C, GY-601 9251
Predator Gasser SE G-23, Fut 3010 servos, JR gyro/servo

PM  EMAIL  GALLERY  Attn:RR  Quote
01-22-2013 12:22 AM  4 years agoPost 6
rbort

rrProfessor

Franklin, MA - USA

My Posts: All  Forum  Topic

643 then the settings are right

That's what I expected you to say on the number. In any case if you get a burp every now and then its OK. Super smooth is not the best idea as you don't know how lean you are. At least with a burp here and there you know you're not super lean.

If you raise the rpms (idle up) and the burps go away then you're right on.

-=>Raja.

MA 1005 Hanson 280, 4142 flts
Spectra 27 3DMax, 3210 flts
Whiplash V1 Hanson 300, 1440 flts
Whiplash V2 Hanson 300, 207 flts

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-28-2013 05:08 PM  4 years agoPost 7
chris6414

rrApprentice

Sneads Ferry, NC USA

My Posts: All  Forum  Topic

You da man Raja. Tturned up my throttle to 25% in the middle and tweaked the LS to just south of 1 1/4 and she doesn't miss a beat no matter how I fly it. Thanks again guys.

Chris

Century Hawk Sport, OS .32, Futaba 7C, GY-601 9251
Predator Gasser SE G-23, Fut 3010 servos, JR gyro/servo

PM  EMAIL  GALLERY  Attn:RR  Quote
01-28-2013 10:26 PM  4 years agoPost 8
rbort

rrProfessor

Franklin, MA - USA

My Posts: All  Forum  Topic

You bet!

Gassers are awesome, Enjoy to the max!

-=>Raja.

MA 1005 Hanson 280, 4142 flts
Spectra 27 3DMax, 3210 flts
Whiplash V1 Hanson 300, 1440 flts
Whiplash V2 Hanson 300, 207 flts

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-03-2013 01:00 AM  4 years agoPost 9
kogibankole

rrKey Veteran

albuquerque/ibadan

My Posts: All  Forum  Topic

maybe your tank breather line got kinked

if im not blade bogging youll find me pack puffing

PM  EMAIL  GALLERY  Attn:RR  Quote
03-19-2013 11:52 PM  4 years agoPost 10
chris6414

rrApprentice

Sneads Ferry, NC USA

My Posts: All  Forum  Topic

257 carb

Well, after some more flying she almost died on a few approaches. I don't know how old the carb is so she may need a rebuild. I picked up the helo used. Decided to swap to a new 257 and stick with pump gas and fired her up today. Choke on about 5 pulls and she fired right up. Let it run for a bit to ensure she was pumping good. In the the hover at 1.5 on LS was rich at 25% thottle opening. Went to about 1.3 turns and that seemed where she liked to be. She idles much better than my 643 did. idles smooth right down just barely grabbing the clutch. Was just in the neighborhood so I couldn't get in any more than two full throttle climbs. She seems to like 1 5/8 on the HS needle. At 1.5 turns she sped up while climbing and only at 77% throttle and sounded like she was going lean. Opened the HS a tad and she was steady in the next few climbs. I really like the idle quality of this one. I think it is the little cut out in the throttle plate that helps the idle circuit that the 643 didn't have. She is keeper. Thanks alot guys for all the advice.

Chris

Century Hawk Sport, OS .32, Futaba 7C, GY-601 9251
Predator Gasser SE G-23, Fut 3010 servos, JR gyro/servo

PM  EMAIL  GALLERY  Attn:RR  Quote
03-22-2013 08:49 PM  4 years agoPost 11
fjk6807

rrNovice

l'ville, ga usa

My Posts: All  Forum  Topic

no 87 octane

Hey glad to hear you got your run problem fixed. You should look at the documentation for your engine. Zenoah says use at least 93 octane gas.

PM  EMAIL  Attn:RR  Quote
03-22-2013 09:37 PM  4 years agoPost 12
turboomni

rrProfessor

East of the Equator

My Posts: All  Forum  Topic

Lots of guys run Coleman camper fuel with no problems and that stuff is around 60 octane if I remember correctly. I use 87 for years with no problems on my Zenoahs.

Setup is everything, All my heli's can fly far better than I can pilot them

PM  EMAIL  GALLERY  Attn:RR  Quote
03-25-2013 02:07 PM  4 years agoPost 13
chris6414

rrApprentice

Sneads Ferry, NC USA

My Posts: All  Forum  Topic

Out of curiosity, I took apart my ole 643 last night. Found some crud residue on the screen. A brown film thick enough to potentially limit flow. Other than that the carb looked clean. That could have been causing my fuel flow issues for sure. For $10 I am going to hold onto it and rebuild for a spare. I realy like the fine tuning of the 257's needles. definately not as course as the 643 was. I think the carb cleaning will be a semi annual event from here on out as I don't get to fly as often as I like. I also am going to start using non ethanol gas at my local station instead of the regular stuff.

Followed advice and went with 1 3/8 on the LS and leaned the HS a bit to 1 1/4 and that seemed to smooth things out even more. She idles good and full throttle is smooth and stable head speed through out. She seemed to be pulling more at full so I turned up the pitch curve a bit to load it up some more and that fixed the speeding up issue. Boy is thing powerful, I only have the throttle plate opening to 77% at full stick as she climbs like a crazy.

Chris

Century Hawk Sport, OS .32, Futaba 7C, GY-601 9251
Predator Gasser SE G-23, Fut 3010 servos, JR gyro/servo

PM  EMAIL  GALLERY  Attn:RR  Quote
03-25-2013 03:28 PM  4 years agoPost 14
rbort

rrProfessor

Franklin, MA - USA

My Posts: All  Forum  Topic

Yes clean it

But if you use a felt clunk you shouldn't get any more stuff in there on the screen unless its some residue from the gas sitting in there for a long time. I usually always pump my carbs dry after flight as well as the tanks and that seems to work well for me with regular gas no issues and no smells at home in the cool basement.

These carbs make all the power early, that is why we fly at around 30% throttle or less to hover. If you put a prop on your engine you might find that the thing runs at 7700 rpms at 77% throttle and maybe not even break 8000 rpms at 100% throttle. Its not going to go to 10k rpms when you go from 3/4 throttle to full throttle. Its more like this:

Idle at 1800 rpms
1/4 stick at 5000 rpms
1/2 stick at 6500 rpms
3/4 stick at 7700 rpms
Wide open at 8000 rpms

Just an example from memory when I get home and fly my taylorcraft I can tell you for sure what its like if you are interested with the G26 Hanson motor, a 17x8 apc prop and the 257 carb.

-=>Raja.

MA 1005 Hanson 280, 4142 flts
Spectra 27 3DMax, 3210 flts
Whiplash V1 Hanson 300, 1440 flts
Whiplash V2 Hanson 300, 207 flts

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-25-2013 04:33 PM  4 years agoPost 15
chris6414

rrApprentice

Sneads Ferry, NC USA

My Posts: All  Forum  Topic

When I got it it had the stock crome clunk in there and I put a MOAS clunk in there from heli direct and new lines. How long do the felt clunks usually last? I also picked up a replacement pack. I also run my tanks dry because I know what is left behind when the gas evaporates in there.

Chris

Century Hawk Sport, OS .32, Futaba 7C, GY-601 9251
Predator Gasser SE G-23, Fut 3010 servos, JR gyro/servo

PM  EMAIL  GALLERY  Attn:RR  Quote
03-25-2013 05:03 PM  4 years agoPost 16
fastflyer20

rrKey Veteran

N. Tonawanda, NY

My Posts: All  Forum  Topic

You can gently get the old screen out with a awl or x-acto knife for a proper cleaning. The tricky part is if the small port holes in the venturi get plugged. You can take multi-strand electrical wire, strip it, use one wire bent at a 90 degrees to clean out the holes. If there is crud behind those holes, it may get plugged again quickly. Removing the soft plug will allow for a proper cleaning of the venturi holes, but the replacement soft plug seems to only be available in the carb repair kit.

Everything must come apart and lots of carb cleaner and compressed air are your best friends when cleaning any carb

PM  EMAIL  GALLERY  Attn:RR  Quote
03-25-2013 09:44 PM  4 years agoPost 17
James Kovach

rrKey Veteran

canton, oh - US

My Posts: All  Forum  Topic

Only the COOL Gasser Guys fly the 257 carb

*disclaimer: These are my opinions. Agree or disagree, Your Call :)
Let'r Rip Tator Chip

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
WATCH
 1 page 1648 views
HelicopterGasser Model RC HelicoptersOther › Gasser carb stuff
 Print TOPIC  Make Suggestion 

 4  Topic Subscribe

Saturday, December 16 - 2:49 pm - Copyright © 2000-2017 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online