2011 FOX 40 Stunt

[BOB ALLAN]

Does anyone have any information on this FOX ?

https://www.rcgroups.com/forums/showthread.php?1402733-Vintage-Glow-Engines/page1372#post49035883

[Perry Rose]

I've had several. All I can say is don't buy it. The venturi is in a square hole. Nothing but leaks. The needle valve is junk.

[Dan McEntee]

   I would think that there is a reason why only one run of them was made, and that should help you decide. If you have to have a Fox.40 Stunt, seek out anyone selling a Lew Woolard rework, I have seen and heard a few of those run and they are impressive.
   Type at you later,
  Dan McEntee

[Ken Culbertson]

I've had several. All I can say is don't buy it. The venturi is in a square hole. Nothing but leaks. The needle valve is junk.

That may explain why the one I had in the 70's was so much trouble.  Powerful when it ran but really hard to set.

In is under the cowl on this one 197x.

ken

[Dan McEntee]

That may explain why the one I had in the 70's was so much trouble.  Powerful when it ran but really hard to set.

ken

    I'm going by memory and may have a specific or two incorrect, but I remember reading several articles on the Fox .40 R/C engine that said it was the most powerful .40 on the market at that time and we are talking about the engine with the tall back plate. The Scepter Flight site probably still has the engine tests. I think they made three different versions of it. One "basic" or "economy" version that had a iron piston and steel liner, then a ringed version, and then when the technology came available, and ABC 'Deluxe" version that came with a spinner and some other goodies. The big issue with these was the carburetor with the high and low speed needle that the average guy could not figure out. OS ruined every one with their easy to adjust carbs. The Fox carb needed to be adjust every time you went flying, but if you knew how to adjust a two speed carb, it was no big deal. Fox eventually came out with another carb for it. Lew Woolard did a complete article that was published in Stunt News on his version of the engine, on which he just took .010" off the bottom of the top lip of the liner to drop it in the case, then added a venturi and such. It's been a long time since I have read that article but I think it was pretty much that simple. The ABC version is the one you want if you decide you want to go that route I think. I don't know what parts supply for pistons, rings and liners are like out there in the world for the others, but they made and sold a lot of them. We sold a lot of them at the shop I was working at and they were popular because it seemed every club had at least one guy that understood the situation and he got to adjust everyone's needle valves for them!!  I think I have at least one of each type and a couple of Lew Woolard's examples.
  Type at you later,
   Dan McEntee

[Brett Buck]

Does anyone have any information on this FOX ?

https://www.rcgroups.com/forums/showthread.php?1402733-Vintage-Glow-Engines/page1372#post49035883

  I haven't see the factory version, but, definitely seen a lot of very very similar "conversions". I thought there was some potential - but not if you are trying to fly it with an 11-6 Rev-Up, which is what most people were attempting. The 45 version, same thing, one of the biggest engine hackery jobs I have ever seen was on one poor Fox 45 that was ground and head gasketed to death for years, never ran right, but kept getting sold as a "modified for stunt" engine multiple times. I think it *probably* needed only a venturi and the right prop (like a 12-3.75 Bolly), but naturally no one ever tried that, and after a few grinder and drill jobs, it would have required piston/line, crankshaft, head, crankcase (or a heli-arc and a milling machine) to put it back to original and start over.

     Brett

[BillP]

That looks like the rc carb sport version converted to venturi with latest nva and different timing.  The last version stock Fox 40s were Sport (iron piston/bushing, BB (iron piston) and BB ABC . 

I like the Fox 40 and thought they were always under rated. Mine were were easy starters and good runners...no problems once you learned the typical fox quirks. Had a sport version rc, That carb was way better than the MKX or EZ carb on the 45-74 engines (currently have a 45cl, 50rc & 60rc). Also had a 40 cl sport (iron piston, bushing) with cast square venturi. The 3rd was a Silver Fox. Even though Fox always touted their engine to turn larger props I didn't experience that to work for me (except for the Silver Fox).

[Dan McEntee]

That looks like the rc carb sport version converted to venturi with latest nva and different timing.  The last version stock Fox 40s were Sport (iron piston/bushing, BB (iron piston) and BB ABC . 

I like the Fox 40 and thought they were always under rated. Mine were were easy starters and good runners...no problems once you learned the typical fox quirks. Had a sport version rc, That carb was way better than the MKX or EZ carb on the 45-74 engines (currently have a 45cl, 50rc & 60rc). Also had a 40 cl sport (iron piston, bushing) with cast square venturi. The 3rd was a Silver Fox. Even though Fox always touted their engine to turn larger props I didn't experience that to work for me (except for the Silver Fox).

   That's what I was remembering except I forgot to mention the part about bearings and bushings. I thought it funny back then that they would offer three versions of the same engine, but that is how popular .40 size R/C airplanes were at the time and the hobby in general was still alive and "traditional." The "Sport" versions I have seen really didn't look like all that great as far as quality and I wondered if they were just reject castings that then managed to build up and sell??  When C/L came back into popularity again in the mid to late 80's then naturally they were available to cross over with varying degrees of success or lack of. I have a couple of Foxes that I do not know the sizes, as they do not have any markings. I got them in pieces in a box of junk, and just sat there and put them together kind of following my nose including the correct bolt on venturis. Both were ringed engines and I'm guessing they were .45 or .50s just from their size. I dropped one into a model I had bought from Walt Brownell years ago and it fit without too much issue, so put a few ground runs on it to sorta seat the ring and took it flying. i remember it running OK, at least well enough to do the pattern with no troubles. I flew it a few times, then put the engine that was in the airplane back in it and sold the airplane ( I think it was a Merco .60??) . The guy that bought it liked it but only got a few flights out of it before it met an untimely demise by running into a bird right at the top pf the wingover, stopped the engine dead and the model in flight, and it turned and dropped straight into the ground at his feet! The carcass of the bird landed right next to it. The model was destroyed but the engine lived to run another day.  Fun times coming up the ladder of stunt!!
  Type at you later,
  Dan McEntee

[BillP]

I just referenced my 1990s bench run notes on the Fox 40bb, abc and bushing....all three turned 12.5 rpms max with 10x6 MAS nylon on 5%x20% all castor. The notes jared my memory that I also had had the abc. No difference between cl and rc but no bench notes on the Silver Fox.

[Jim z]

   This Fox .40 stunt is not just the fox .40 with a venturi...This engine came from the factory with mods done 
    similar to the Lew Woolard mods...for stunt runs.  The heads were modified  and  cylinder timing mods.
    done with specs. provided by Lew Woolard.   
    I had several of these engines and all ran very well.  I changed out the needle valve to a super tiger style
    and sealed up around the venturi to prevent air leaks...I also replaced some venturis by ones provided by Tom
    Dixon  and Lew Woolard.    Tom Dixon back in the 90's  used to modify the Fox 40  which made excellent
    stunt engines...
   The Fox factory would also sell  a complete stunt kit which included the Piston and liner and heads with
   all mods done  .