I just got a Fox 61 Eagle, it is in pristeen shape, I know nothing about this engine any info woulld really be appreciated Mike

Thanks for moving it David, I guess I had a :seniors moment I see I misspelled Eagle in the heading Mike"

It sure is different from any Fox Eagle I've seen so far, I just had a friends Eagle III .60 here for a few days and it was different also. Does that one have a baffled piston?

That looks familiar, like an early to mid 70's vintage, and yep, it's a loop scavenged, baffled piston, and should be 2 rings...
They're good, long running engines, just take your time and break it in carefully, and use fuel with plenty of castor. I would say no more than 10% nitro too. An 11x7 or 12x6 prop and a Fox long plug w/ idle bar works well...
Don't expect modern day standards performance, but for sport flying, it'll work well, and last a long time. I "inherited" a couple that my childhood "mentor" left me before he died that must have (I don't know how many) hundreds of flights on 'em...

As proptop says, use a fuel with at least 20% (more is better) and preferably all castor oil. 5% nitro is all you want. Will take a lot of breaking time but will last forever and put out gobs of power after proper breakin.

Mike its a fine engine for its time. I bought one last year NIB and have run it enough to break it in. Duke Fox made several different carbs for this series of engine. If it has the vane shaped barrel in the carb then the adjustment procedure is different from most engines. The more modern Fox carbs will work and they also make an adapter with a round hole in it that can use a "standard" carb. I've tried an OS and have a Perry for it. but the Fox works ok once you get it set right. The only problem with this engine is the original muffler is quite loud by today's standards. I've been working on adapting an OS muffler to this engine, but haven't tried it yet. I run mine on an 80s vintage Midwest Aerosport kit I built, only the radio is modern. Have fun!
Tim

For more information on the Fox Eagle I .60 follow this link:
http://www.flitelinesolutions.com/eagle1.html
Included on this page is information on how to adapt a Super Tiger muffler.

Check out the muffler on the Flightline website. It works super!

Hey Kimhoff, is that your muff. mod I see on there? Looks good!
I have an old Semco on one of mine...the flow thru style that doesn't "muffle" much!

Proptop,

That is mine. Made a real sweet motor out of it. I had a Fox muffler on it and it always overheated. Put this on there and runs great.

Kim, those SuperTigre Swing mufflers sure are versatile, you can see I modified the stacks a little to make room for the bolts.

Re: your Eagle .61 -- All the info you have received is good! Just one thing -- the fuel suction is a little weak, so keep the fuel tank CLOSE, and the center of the tank needs to be on the center line of the carb. I didn't, and it cost me a scratch built VK Cherokee. I had better luck mounting the engine on its side. Other than that, it is a good sport engine.

Vaughan Sharp

I have one of those FOX Eagle engines mounted on an original Phil Kraft Ugly Stick, my "retro-plane"! The engine runs great and is pretty light for it's displacement. When properly broken in and tuned it will run literally forever!

The problem is that most modelers don't bother to learn how to properly tune this unique engine.

The carb has two jets, a low speed and a high speed. The low speed jet is ALWAYS FULL OPEN! At idle the high speed jet is completely closed and the low speed FULL OPEN. At high throttle settings the mixture is a combination of the low speed jet (ALWAYS FULL OPEN) and the high speed jet.

Therefore it is VERY important to set the low speed jet first before setting the high speed jet. If you don't do it this way you will most likely NEVER get the engine rich enough at high speed and you will burn it up before you figure it all out.

Get some fuel tubing and set the throttle to idle, just barely open about as much as a small stick pin. Connect the tubing and blow into the engine, adjust the idle mixture until air just barely flows. This is your starting point.

Start the engine at idle and adjust the low speed mixture for a reliable slightly rich idle. Then open the throttle to full and set the high speed needle. Re check the idle mixture and fly.

If you can't seem to get the high speed rich enough then the LOW speed jet is too lean. Remember the low speed jet is always full open ; therefore the high speed mixture is a combination of the low + the high mixture setting.

If this is too much for you, buy a perry carb and adapter.

These are great running engines when properly set, and you can buy them on EBAY for less than $50.00 in new condition because no one bothers to learn how to set them up.

Good luck!

Mike,


Since this engine is clearly biased toward the lower part of the RPM band, I would say an 11x7 prop is too small.
An 11x8 is the absolute minimum, for keeping this engine in 'the meat' of its HP curve.

A 12x6 is similar in load and will be about 300 RPM down.

As I recall this engine runs quite well on a 11-7. Probably about 12K.