Mak Gyver

My Feedback: (1)

I have purchased a Fox 40 2S from a friend thats had it put up for about 12 years. It is ringed and ball bearing. Still new never had fuel in it still in the box and plastic bag. I can get it to run at idle and at top end. Idling around 1/4~1/2 throttle then go to full throttle it dies. Tried changing plug removed the original fox plug with the idle bar replaced with #8 OS same thing. Running 15% cool power full synthetic. Any suggestions on what could be happening?

submikester

My Feedback: (6)

If memory serves me; those Fox engines liked a lower nitro. Is that the two needle carb or the air bleed carb? Also, that older engine on Full Synth oils is probably a bad idea. Get some castor and lower the nitro down to 5%. What prop are you using on it?

TFF

http://www3.bc.sympatico.ca/fliteline/

They have the answers. If it is a two needle carb the low end has to be set first then the high, but you have to go back and forth low-high, low-high untill it is right, you cant go high low.

DarZeelon

McGyver,


You should, as submikester wrote, use fuel that has a great deal of castor oil.

Some engines, particularly from the late Duke Fox, just don't behave well with CruelPower, even if they are ringed and Omega does say it is the right fuel.

Get some Sig Champion, or PowerMaster GMA 5% fuel and it will run much better.
The order of adjusting the carburettor is critical!

It will not work well, if you adjust the high-speed needle first.

Charley

My Feedback: (2)

That's the .40 BB: http://www3.bc.sympatico.ca/flitelin...s/40-2jet.html has the manual.

The Duke's fuel they recommend had around 22% castor content. I had success with them on 10% nitro, 18% castor.

CR

Sport_Pilot

My ringed .50 runs just fine with Omega 5% nitro. They need some castor, but not 100% as Duke recommended.

GarySS

My Feedback: (13)

I had two of them. Extremely powerful on 10% fuel, but I was able to land under power only about 1/3 of the time. The engine ususally quit while on the last part of the final approach so it wasn't too much of a problem. I just never felt comfortable using the throttle as a 4th control. Got rid of them as well as all of my 2-cycles except a Thunder Tiger .36----what a sweetheart!!

Charley

My Feedback: (2)

If you'd ever run it on all-castor fuel, you'd know the difference. I'm running my .50 on a blend now too. It doesn't run as well as it did on all-castor.

CR

Broken Wings

My Feedback: (20)

+1

Sport_Pilot

It runs perfect either way, but with slightly less power and more mess with castor. Most ringed Fox engines run no differant on synthetic oil than other engines. An exception may be some of the older double ringed engines.

Also some of the early engines needed the castor during a very long break in. I think the modern engines break in a little easier, even the ones of the same design. They are not as tight new.

Charley

My Feedback: (2)

Bat feathers.

CR

Sport_Pilot

You will get more performance with a synthetic/castor mix than pure castor in most any engine. Explain why a well broken in Fox is any differant? As opposed to a not quite broken in Fox which for older ones is much of its life.

From Flitline Solutions

"After extensive testing, over many years, we have determined that, with reasonable needle settings, most Fox RC engines generally run well, with acceptable durability, using the synthetic/castor blends produced by Morgan (Omega), Powermaster and Sig. However, it is likely that any quality fuel containing some castor oil in the mix will be ok. Since switching from the castor only fuel that we used decades ago, we have not noticed a significant decrease in engine longevity. Only that the engines run cleaner and without the need for relatively frequent disassembly for de-varnishing as was required in the past. But, again, we must stress this assumes reasonable needle settings. With decades of experience running model engines, and Fox engines in particular, we are confident in our ability to consistently achieve proper settings. If you are not sure of your ability to properly set the needle to avoid lean runs, you can always add a bit more castor to your fuel for added safety margin. (Sig fuel contains more castor than most blends)."

NM2K

My Feedback: (14)

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You will kill that Fox deader than a door nail if you continue to run straight synthetic oil in it. Seriously, that is bad ju-ju.

Does the piston have a baffle on top? If it does, you need to run the idle bar plug.

If it sat for quite a while (assuming it has been broken-in previously), it is possible that the carb is a little gunked up from dried oil. Have no fear. Just run a few tanks of fuel through it and it will return to normal eventually. Be patient.

Forget the OS#8 plug. Save it for an OS or Sanye clone.


Ed Cregger

Charley

My Feedback: (2)

Sport,

You're talking in absolutes, where your reference paragraph is full of equivocations and caveats. Not the same thing. I don't feel the need to explain anything. We'll just have to agree to disagree.

Regards,

CR

Sport_Pilot

I am talking about personal experiance matching the testing and experiance from those of Fliteline Solutions. Yes a young engine that is not fully broken in will run better with all castor because the thicker oil will seal the rings better, but when well broken in it will run as well as any other brand on a castor synthitic mix.

jessiej

My ball-bearing Foxes, two .15s a .40 two .50s, a couple of 60s and a .74, all run very well indeed on a synthetic-castor blend. All my bushing Foxes, a dozen or so, are of 50s-60s vintage and I run them on all castor, 25-28%. As I recall all of my older Fox engines except the .59s are lapped piston.

jess