1QwkSport2.5r

It was sold to me as a "low time" unit... Turns out the piston was not stock - it appeared someone tried milling another ring groove into the piston and stopped after the groove was a few thou deep. It didn't have the proper sized ring either - it needed a .59 ring (something like .005-.010" thicker than stock ring) to not clatter (ring flopping around in groove) when running. And the cylinder liner was barrel shaped - narrow on top and bottom and oversize in the middle. Hardly a good arrangement for a well running and behaving engine. It ran for a tank or two, ran barely okay for its size.. About 2000-3000rpm short of "normal". After new Bowman ring went in and following typical break-in technique, compression got worse and worse.. That's when we measured the liner to find the cause. Found another used P/L and ended with the same problem. That engines fate changed when we found an MDS .40 ABC P/L fit the crankcase. Made up some parts to fit it all together and so far it's ran for more time like this than it did on original Fox parts. Granted I was never able to find NOS parts. They're almost nonexistent even on eBay!

I have had several other Fox engines... Some ran okay, and some were real pieces of crap. The same can be said of other makes of engines. In a lot of cases, I'd take a Fox over an OS, and I really don't care for Fox much. I currently have a c-case ABC .40 that runs okay, an unused .46ABC, the FrankenFox (originally a .50, now a .42ABC), and another .50. If I had a way to make my Davis Diesel head fit the .46, is sell off the other ones. I much prefer Enya and SuperTigre (Italy) and Dub Jett build's some nice pieces here in the US of A.

50+AirYears

Now, THAT makes sense. And I agree about Fox over OS. I once traded a Fox baffle .15RC for an OS .30 RC and $5.00. The other guy got the better part of the deal. I have a couple Fox .19s that outperform that .30.
Of course, I did for a while get decent performance out of that .30. Pulled the throttle, turned a straight venturi for it (0.26"?) and ran it in a SAM OT RC plane for a while. A definite improvement.

1QwkSport2.5r

I still feel that Foxes are more fragile than other makes. Second hand or not, I have other engines that were beat harder that I have full confidence in how they run and perform. I don't have the same confidence in Fox. But at any rate, the ones I have do run okay for now with the exception of the latest .50 and .46 having not been run by me.

RichardGee

My Feedback: (156)

I never had any Fox that ran better than an O.S. or Super Tiger. My K&B's generally ran better than my Fox's. I still own Fox's, but only for collecting purposes... I have N.I.B: Fox Hawk 60, Eagle IV 60 ABC, .25 baffle w/muffler, and BLACK 35 Stunt Anniversary edition with 24 karat gold trim. It is sad that Fox went the way of the Dodo Bird, but it truly was their own fault. Besides their funky carburetors, poor quality fit and finish did them in.

Sport_Pilot

Never had a Fox with poor fit other than some had loose needles. But when Fox went out of business they had an excellent carb with Teflon sealed needles. My Fox .50 does have the old style needles but runs great but does weep a bit of fuel out of the needles. The Fox stunt engine was an excellent out of the box stunt engine that ran great and gave a good 4-2-4 break without trying. If it wore out you were using fuel with synthetic oil, if it ran hot you ran fuel with less than 25% oil. Almost always started first flip. But if the plane was overweight it did not have enough power. My Fox .50 runs as good as any .46 but needs a bit larger prop. I have a used Fox .46 but have not tried it yet. Looking for a newer Fox with the latest twin needle carb off and on, but have not seen one on any of the ads both here and elsewhere. Also have a Fox .15 that ran great. OS runs great for a year or two then craps out.

RichardGee

My Feedback: (156)

No comparison in quality to O.S., Enya, HB, HP, YS, Super Tiger. Fit and finish of these imports far exceeded Fox, both inside and out. While not every import handled better than a Fox, sadly, 90% of them did. I owned and flew many Foxes. Even fed them a steady diet of Fox fuel. Finally got tired of tinkering and went to Super Tiger. Finally had the money to go with O.S. and there is simply no comparison. And as we have seen, the market place seems to agree as O.S. is still going strong and Fox is no more. I'm not happy about it, as I always try to buy American when I can get even remotely close to a comparable product, but in the case of engines, Fox was always two decades behind O.S. in quality. It took them far too long to fix their carburetors and when they knew they had a rotten engine, they refused to pull it off the shelf or fix it in a timely manner. IF Fox had the customer service of (American company) Desert Aircraft engines, they would still be in business, even if it was limited to UC engines and gassers.

1QwkSport2.5r

If I had a dollar for every peeled OS nickel liner, I'd be rich. There were some Fox liners that peeled, but at least they did it right and used real chrome. OS's "quality" is a functional carb and a box that breaks the engine in for you. Beyond that, OS is junk in my book. I put Super Tigre (Italian made) above OS.. Yeah, OS is still around and ST isn't, but nobody is willing to wait for an engine to break in to enjoy it. SuperTigre, HB, Enya, K&B, and Fox were not instant gratification engines, OS engines are. That's why they're so successful. Just try to warranty a peeled liner..

RichardGee

My Feedback: (156)

Hmmm... and here I thought ELECTRIC was the "instant gratification" choice for power..? We'll agree to disagree. I still like to run Fox engines just for nostalgia sake. Had a .45 that was pretty good and a .46 that was almost as good as one of the economy O.S. engines. Never had an O.S. engine come apart, wear out early, be hard to start, or unexpectedly quit on me. Like any glow, I always run my engines slightly rich, use good fuel, and unlike a Fox, after gallons through my O.S. engines, they still look new. Had a couple of K&Bs (.61 twisty and Screamin .48) that are superb running glow engines. As good as anything else I've run and better in every way than a Fox. Obviously Fox did some things right to have lasted as long as they did, but unfortunately they did more things wrong. Carburetion was their biggest long-term problem. They had several engines that were WAY over-compressed and some with both too much compression and combustion chamber design that adding head gaskets would not fix. Porting was also a big problem on some of their engines.... the Eagle III and 1.20 twin come to mind. When combined with a finicky carburetor, such engines were relegated to collecting, not flying. Take the cheapest O.S. plain bearing engine and compare it to a Fox plain bearing engine. Absolutely no comparison in fit or finish. Running characteristics are just as dissimilar and both engines require a good amount of oil and NEVER to be run too lean. Since I have never had an O.S. engine fail, I have no experience with the warranty, but I did have a Super Tiger eat a piston pin retainer clip (because I had dieselized it with a Davis head - something else I would never recommend) and Tower Hobbies warrantied the engine. To their credit, when I was dieselizing a Fox .74, Charles at Fox worked with me to provide a smaller carburetor and extra head gaskets and was very engaged in the process and results. Like all diesels, the big Fox had few pluses and way too many minuses to be a practical flying and throttling engine. Fox GAS engines, on the other hand, boast VERY nice fit and finish. It's just unfortunate they got into the game a bit late and had insurmountable competition.

1QwkSport2.5r

I have a ST .45 ABC that was given to me along with a Davis head and it runs flawlessly to this day. Of course it's the Italian made version which I put a few notches above the Chinese made engines. I've not had any engines eat circlips EXCEPT a small cases .40 that did it 3 or 4 times. It still runs - even on diesel - with decent power, but it doesn't idle for beans below 3k. The SuperTigre .45s I have don't have the little leg on the circlip that most engines come with - they have a "C" clip and a recess in the piston for removing the circlip. A much better system than the typical circlip styles we see.

I have some OS engines - most were just given to me and one I actually purchased. The one I bought is an FP .10 that was new from an estate sale. The others include an old Max III .15, Max .25, Max-H .40, .25FSR (ferrous, has new P/L in it now), .60FSR, and a .46FX (actually two of them but one has a badly peeled liner). I'm keeping the Max III .15, the two FSRs, and the FP .10, the rest are being sold or given to friends. The peeled FX will get a new ASP .46 P/L/R and then probably sold. I have too many .45 sized engines already. The Foxes I have are really bench queens.. I doubt I'll fly them unless I find a .40 sized ship that isn't a 3D profile plane.

My favorite American made engines are from Dub Jett. I have two of his BSE engines and they are fantastic in every way.

hsukaria

When we compare engines, we also have factor in the price. It is not a fair comparison to put a heavily used Fox engine purchased for $25 against a $325 Jett engine. Of course the Jett is going to be much better. The same applies to the OS engines, their price is so high it's silly. I have a few Fox engines that run reasonably well even though they have seen extensive use and purchased real cheap. On the other hand, one of the few engines I purchased new is a OS 55AX that peeled the liner despite costing me a good bit of money. So I consider the old Fox engines a much better deal than the OS with a peeled liner. Of course I have a great OS 46SF with a ringed piston that i hope to keep for a long time. I purchased that one used real cheap. I guess I won't be buying new engines for a while. Except maybe a Dub Jett.

1QwkSport2.5r

I was never implying to compare a beat up Fox to a BSE Jett. That would be like comparing month old dog poo to a 20 carat diamond. But do go back and look at what Fox's retail prices were for their engines. I have a price list dated 2010 - they even have some DLE engines listed. Retail prices are what you would have paid without a trade-in. The factory price was with trade in I believe. Fox .40 RC Deluxe retail 159.95/factory 119.95, .46ABC R186.95/F140.20, .60 R219.95/F164.95. Hell, a Fox .35 Stunt ceramic - get this - $225! Regular super stunt .35 was $150. Compare those prices to the OS or Thunder Tiger of the day! In those days, a TT Pro .46 was less than $100 and was almost 100% finicky free out of the box. The reasons Fox went south (no pun intended) was they A) weren't innovating - selling 1970s designs for 2000s pricing when the 2000s designs ran better and made more power for less money, and B) their pricing was in outer space. Now granted, labor costs in the USA are higher - that's a given. It's hard to compete with the imports, but for a company to stay alive, they have to shift gears and innovate. Imagine if Fox designed and sold small gas engines in the 6-15cc range that ran trouble free out of the box...

I think my .46 is well fitted and the finish is the best of any of the Foxes I've had, but their Carburetors do leave some things to be desired. Leaky needle valves are annoying. I think one of the older manuals I have (perhaps for my very early .40 compact (series V)) mentions putting fuel tubing on the needle valve out of the box... That just screams "crude". I have a Perry carb adapter and Perry carb that I use on my FrankenFox - it does throttle better than the MKx carb does and it doesn't need to have the needle re-profiled to do so.

The he age of "kitted" engines is over. If they ever make engines again, hopefully they can make up a stockpile of their newest carb. It's been said to be their best carb ever. I'd love to try one sometime, but finding old stock parts that aren't beat to snot is impossible.

hsukaria

I have tried 3 Fox carb types, the MkX, EZJUST, and their newest 2 needle. The new 2 needle carb is the best I have ever messed with, any brand. I am ok with EZJUST, but I do think the MkX needles are flimsy and wobbly. In one occassion, I replace the MkX carb with a EZJUST because was leary about those fragile needles on the MkX.

1QwkSport2.5r

If you ever decide to part with the new 2-needle carb or willing to let me borrow it to try out, let me know. I've looked all over and can never find them for sale. It's gonna snow soon, so I'm getting ready to mothball most of my engines.

hsukaria

If you are looking for an ARF 40, this world is saturated with them. But for kits, you can't go wrong with a Sig 4 Star 40, good flier for any level of experience. I also think the Sig Kavalier is an excellent plane. I plan to build a Sig Kavalier this coming winter and put the Fox 45 that I rebuilt on it and most likely use a tuned pipe "just for kicks".

hsukaria

As long as I have glow engines, I plan to keep that Fox new carb. However, I won't be needing it until later this winter when I build the Sig Kavalier. If you want to borrow it for testing this Fall before the freezing weather comes, you are welcome to it. The new carb has the same barrel and body as the others, just the needles are different. So, it should tune just like the MkX carbs without the fragility.

1QwkSport2.5r

I'm not an ARF guy, so I'd want to build a kit for sure. I have a huge pile of plans for a ton of 1/2a RC ships that my buddy gave me that I need to sift through. I have enough little .15s that I will need to use.. .15s are a bit big for 1/2a, so if probably need to scale the plans up a little..

hsukaria

I'm also going through a .15 kick right now. I have 4 .15 through .20 engines: OS-Max 20 bushing(old with a strap-on muffler) that I am flying on a HOB Texan, a Norvel 15 BB that I plan on putting on a modified Screamin Demon, an AP 15 Yellow Jacket that I plan on putting on a PICA 1/12 ME109, and a Norvel 15 bushing that is looking for a plane. All of these are or will be without landing gear to reduce weight and drag. That also allows for flying off a grass field and snow. I might fly one this winter and land on snow, might work out ok.

For your 1/2a plans, a general rule of thumb is to scale them up to a wingspan of around 40 in. to make them the right size for a .15 engine.

Sport_Pilot

A lot of 1/2a models are 40" span, those made for a Norvel are larger than that. I have a Global T6 that is 44" and it is a .20 size, but many flown with a .15. A trainer type .15 is about 48" - 50" in span and a fast .15 would be about 42" in span.

hsukaria

I guess it would depend on the type of plane. My House of Balsa Texan is about 42 inch and the PICA ME109 is 34 inch wingspan. The 42 inch Texan is fairly fast with the old .20 (about the same power as a modern .15). The only time I wish it had more power is when hand-launching it, it could use more static thrust then. I'm trying to find ways to make the airframe lighter to make the handlaunch less painful.

1QwkSport2.5r

I'll have to measure the wingspan of my Norvel Neofun 1/2a trainer. It's probably in the 34-36" wing span area I think. It's only a 3-channel plane (rudder/elevator/throttle). It flew like a tail heavy brick with a AP .061. My buddy got it used with a AME .061 on it. It was an ARF too. My FP .10 is on it now which should fly it much better than the .061 it had before.

Sport_Pilot

HOB Texan is same a Global Texan and it is 44". And it is a fast .20 sized model often used in sport pylon racing. The size is a modern engine size because it came out in the 80's or 90's when most two stroke engines were actually faster than now. The newer sport model engines were detuned with better mufflers for lower noise. Many modern SPORT engines are about the same or slightly faster than the old competitive cross flow models.

Sport_Pilot

That's a bit small for a Novel powered trainer. Here is a more typical version.

http://ironsidemodels.com/st5he1trrcba.html

The older trainers which were sized for the reed valve Baby Bee and the like were about that size. I suspect the Neofun may be fast for a trainer.

hsukaria

That is a nice website, lots of kits.

hsukaria

Ok, since this is a Fox engines forum, what is the Fox 15 RC like? Any experiences? Pictures? Data? etc... I have 3 brands of small 15-size engines except Fox.

Sport_Pilot

The Fox is a very good .15 Ball bearing engine with more power than a OS FP or LA. But it is iron piston on iron sleeve so all castor fuel. One of the best twin needle Fox carbs.