foxtrot

My Feedback: (2)

I have an O.S. 46FX.....its performed very well until recently. It will run fine on the ground, in the air for about 3 minutes and wham....it losses power. It will run sluggish for about 30 seconds then die. Any tips?? The fuel system is fine, carb is level with fuel tank etc....its performed well for about 2 years until now. could the engine just be worn out?

William Robison

My Feedback: (3)

Steve:

There's a good chance you've been bitten by the ABN bug that OS swears does not exist. With a peeled liner the FX will generally run well for a couple minutes, then when everything is up to temp, it shuts down.

Pop the head and look.

If you see brass take any of three options. If it's still in warranty send it to Horizon for free repair. If it's not too long out of warranty they may still fix it at no charge.

If warranty is out, you can order the piston and liner set for the Magnum XLS 46 at a cost of $37.99 from Hobby People, when you install it (it drops in, fits like the OS parts) you will have the engine you expected OS to sell you originally. Genuine ABC.

Third option is just buy the complete Magnum XLS 46 engine. If you buy the p/l set and new bearings for your FX the new Magnum isn't much more expensive. And it's a lot less expensive than the parts from OS.

Bill.

foxtrot

My Feedback: (2)

Thanks for the info.......I will break her apart tonight to see......

foxtrot

My Feedback: (2)

Well, I popped the head off....and no brass..........

William Robison

My Feedback: (3)

Hmmm... Does it still have"Pinch" when you turn the crank and get the piston to the top? If not the piston and liner set could just be worn out. If yes, then there has to be something we've all missed.

At this moment I'm going to wait for your answer, and then I'll have to lean back, review the posts, and try to do some thinking. And that's very hard for me.

Haw.

Bill.

foxtrot

My Feedback: (2)

yeah, its still got good compression....I did notice though when I took the head off, the 6 bolts seemed to be a bit loose....I could tighten them about a 1/4 of a turn.....maybe they were too loose? I even tried to reset the low speed screw....thought maybe it was getting too much fuel.....didnt work though. I did notice that when I carried the plane off the runway( from making a "deadstick" landing)that the fuel would kinda "flow " back and forth through the fuel line to the carb as I was walking.....also, for a while, It would flood just sitting there......I would have to take off the glow plug and empty out the cylinder of fuel to avoid fuel lock. I'm about ready to just give up and get a new engine!

William Robison

My Feedback: (3)

Steve:

The loose head would indeed give exactly the same symptom as a peeled liner. Put it back on, be careful to tighten it evenly, and try again. Remember Scarlett O'Hara's closing line - "Tomorrow is another day."

Bill.

air mail rcu

Are you sure about the fuel tank. Did you take it out and look at it. Sounds to me like the clunk might be forward or there might be a cut in the clunk line. After you use some fuel it starts to suck air. Worth a look.

foxtrot

My Feedback: (2)

well, I tightened it all back down, checked all fuel lines and the tank.....all seems to be good to go, I will try it out tomorrow.....

superfly13_69

I have the exact same symptoms as Foxtrot. I did pull the head and found alot of brass showing at the top of the cylinder. Even at the edges of the piston, too. I'd send pics but it's boxed up ready to ship off. Fortunately mine's still under warranty, so it's free right Bill?

Superfly

William Robison

My Feedback: (3)

Fly:

Should be free if the engine is within its warranty period.

Bill.

ben beyer

My Feedback: (23)

What glow plug are you using? I had the same problem except mine isn't as old. I'd start it and it would run fine and then quit a few minutes later. I changed out the glow plug and no problems since. I was using a cheapy Fox (which i've had success with in the past) and so I decided to opt for an OS #8 and not a single problem since. Also check the low end adjustment to...

rica1

My Feedback: (32)

If you have changed props to a larger than recommended your eng will build up heat and stop. If you run it to lean it will over heat. If you have a lot of dark residue on the piston when you look thru the exhaust, it probably needs to be devarnished. What prop are you using? What plug? What fuel? Have you changed the eng to another plane or changed the fuel tank? Ask the engine expert where you fly to look at it. Maybe they will see something that your overlooking. I have run my 46FX for about 5 yrs now and it runs a little hot with an OS #8 plug, 12.25X3.75 with 5 to 10% nitro. Good luck!

Steve108

My Feedback: (36)

Same thing happened to my FX with the stalling in air problem. For me it was bad fuel. It got watered down by moisture. Try some fresh fuel!

superfly13_69

I just got my 46FX back from Hobby Services. Man, they replaced the cylinder liner, piston, AND the front AND rear bearings!!!! They said some crap about running it lean at some point, but I know that's not true. I had residue from start to finish on that engine. Anyway, to make a long story short, yes they do honor their warranty, and yes it did fix the problem. It runs like a champ again!

Superfly

jaka

Hi!
Sounds as if you simply run it too lean.....
Regards!
Jan K

superfly13_69

That's what I'm saying... I DIDN'T run it lean.

tango28charlie

Fox, If the engine is flooding just sitting there, you might check the level of your fuel tank versus the level of the carburetor.
Cheers, Charlie

nedp

My Feedback: (4)

What ever happened with this problem ?