CRRC Pro GF26I

[ec121]

If you can safely reach the box, try running it on the ground and tapping on the box. I used to do that when I was working on electronic calculators a long time ago. A cold solder joint will show up from the vibrations.

[Barney11]

Quick question, might need a long answer

I have my 26 in a seagull extra 180. It has about 3 gallons through it and using a sy 16x8 prop.
Recently it has decided that it will only start at about 2/3 throttle, once running it can be dropped to idle and will sit there all day and still open up well.
Starting warm is still the same, needs to be 2/3 open to fire & run.

Wondering if any of you have had the same problem? tends to take whoever is holding the plane by surprise!!

Thanks,
Iain.

[GreyEagle]

Prime it 1st so It's wet - Look in the cowl to see if the fuel is coming to the carb.

Most likley your walbro filter screen in side the carb is full of junk from a contaminated fuel jug and and the rubber impellor from your crank pump is breaking down plugging the screen.

Pull the screen clean it- put it back in before some one get's hurt - never start at 2/3rd's.

Any body else confirm my bad ignition ???? Ever seen a similar problem ????

[Barney11]

Thanks Greyeagle,

I've had the carb out and cleaned, so the screen is clear.
The engine is choked & primed with ignition off until there is fuel at the carb, ignition on, choke on, couple of flips till it pops, choke off, few more flips & away it goes, but only at 2/3 open, below that & you could spend all day with just the occasional pop.
The main reason i'm asking is for safety, I never start this plane now without it being restrained by the tail and with a well warned volunteer holding by the wing, and I still have only flown it a few times this summer when I know I can get help.
Thanks,
Iain

[ec121]

Is the low end needle clean? What about a servo/linkage change? Does it come back to a good idle after starting?

[GreyEagle]

Still Testing : Plug and Prop

Like to inguire about prop size's an common RPM result's: What's the common flavor with best results

Presently running a 16" X 8 woody achieving a bench load of 7440 thinking - I maybe loading the motor too much

Prefer to switch from the OEM Plug to a NKG brand - anyone know the direct cross #

[Jedijody]

I bench test them with a 17x8 Hawk, they all should hit 7400-7500 RPM with it and that is not to much load. The NGK plug is the same as the Torch number on the OEM plug, CMR7H.

[GreyEagle]

Since thanx Jodi ! I think we are getting closer. During our testing we are learning more each time. Seems the problem goes some what away when flying at 50% throttle -- it ceases completely.

Know I'm considering the Torch plug is mis firing or breaking down at High Speed -- or their is a timming issue with the current position of the inductive pickup censor. Plug swap is a easy one.

Checking the position or adjustment of the inductive pick up has me a bit nervous. Is their a detailed procedure to confirm or adjust the pick up based upon TDC or the position of the magnet. ??? ANy ball park recommendations ???

Never had a problem starting it with my electric -- although it seems to start as a pretty fast RPM.

I hate to guess : But could the timing be to far advanced ??

Think I'm hearing a High Speed Mis Fire

[Wingman26]

Here's how to do it

YouTube - Broadcast Yourself.

[GreyEagle]

Thank you Wing Man : I want to see what the factory settings are / Got my degree wheel made / Ready to go !

Just wondering what I'm supposed to find ?? 23 degree's ?? 26 degree's ???

I'll repost what the finding's are / Maybe these are getting out with out the proper timeing /

[Wingman26]

28 degrees if you can get there, closest I could get mine was about 30 degrees before you run out of adjustment, that's close enough.

Mine was much higher before it was adjusted down.

[ec121]

I took a Dremel tool and made the slots longer to get to the proper timing. You can also use a hose clamp or big zip tie. Done that before also. When you get to the desired setting, make a mark on the end of the switch bracket, and it is easy to verify later.

[pe reivers]

Zip tie works well for fastening the CDI hall sensor.

On carbs:
some chinese carbs are assembled using quite old stock, that is not resistant to our modern oxygenated gas. (been there)
Replace the membrane set if the rubber parts even show a hint of stiffening/hardening. Thease parts should be soft and flexible. This is the main reason for ill tempered carbs.

[GreyEagle]

OH MY ! You guy's are just great ! Hard to believe I've never done this before in 35 year's of building ! " My 1st CDI " !!!
All my other gasser's have Mag's. Well I found { 45 } degree's before TDC and that 's dead money !

Looks Like I've got a little shifting to do -- and 28 degree's is going to be hard to get with the adjustment slot's given.

[pe reivers]

Like I said: Zip ties work OK.
Not all engines need to be set at 28°. Some only need 20°, whilst other work well at 40°.
The CDI unit delays the spark by about 20° when starting with a health flip, so when set at 40° the engine will fire at 20° BTDC. For starting, flip like you mean business, and NEVER play with the prop and with live ignition!