More Fun with Foxes !

Kim Sun Jun 03, 2012 9:54 am

Made a quick test run this morning of my Uncle Wayne's ancient Fox .35.

It cranked up like Bobby and I had just flown it last Sunday, as opposed to it's 30-some-odd-years in the bottom of Wayne's engine box. If I'd had some CCR cranked up on the HHR's stereo, the sounds, smoke, and exhaust smell would have been pure 1968 !

I haven't taken much effort to clean it up, just flushed the N.V. assy and installed a new glow plug. With the needle setting at the familiar "Fox Two-Stroke Break" it turned an M.A. 10-6 in the mid-9's on Glowplugboy's 10% fuel.

Ivanhoe Sun Jun 03, 2012 5:41 pm

Nice one, Kim, that's a classic engine. Back in the day the Fox .35 was THE engine you yearned for if you flew stunt, trouble was, imported engines were out of the reach of us poor schoolboys, so I, for one, never owed one, even now the only larger Fox I have is a .15, now you have gone and re-ignited my need to own a 35, and I shall be haunting EBay again!

Get thee behind me!

proctor Sun Jun 03, 2012 7:02 pm

Nice one, the one I owned back in the late 70's I flew in a kind
wild stunt. It never missed a beat,a great engine. I seem to
remember it was kind of plated all over, not chrome but a kind
of shiny zinc plate. Would that be right?
Got stolen when all my personal stuff was being shipped to Norway
for a construction job.
John

Ken Cook Sun Jun 03, 2012 7:11 pm

Kim, I can't say enough about the Fox.35. Your example there is pretty cool. That's a large bypass model circa 1960? with the 35 displacement casted onto the case. My earliest is what I believe to be the 1958 version as mine has no casting web obstructions in the exhaust port. The old Fox.35's can be extremely difficult to install the cylinder head on properly. The case is very thin and can distort easily.

My friend actually performs the black magic required to install them. This is done with all the parts completely cleaned and non oiled. As the head bolts are tightened there should be no binds whatsoever through the pistons travel. This is easier said then done. Sometimes this can take a good bit of fiddling and finding the correct head bolt to tighten.

One thing I always like to check in the Fox is the conrod to wristpin. The conrod gets glued to the wristpin and during the operation of the engine it can easily egg out the hole in the piston. Removing the backplate, you can snake a allen key around the conrod and pry off of the crank web. If the rod isn't floating freely back and forth on the wrist pin this will need to be freed up.Penetrating oil and heat work well.

Removing the back plate of course is going to require a new gasket as well. Not a bad idea anyhow for the ole girl. A fox just won't run if there's a leak in the backplate. The Fox has a very fragile egg shell like casted backplate which has those 3 screws holding it on. Those ears easily distort. Keep in mind that there is no indexing on a Fox.35's cylinder. If you remove it, there's no way to put it back into the case the same way it was. This is quite important as the fine scratches on the cylinder walls and piston won't align as they once were.

I try and put a scratch across the rim of the cylinder sleeve onto the case to give some sort of reference. Bottom line though, if it doesn't need to be removed leave it. Misalignment can result in performance loss. A gunky blackened Fox works better than a new one. Kim that engine is calling for you to install it in a Ringmaster. The Fox.35 is a great engine in my opinion and regardless of how the Fox haters feel, I can almost bet all of them once flew it. Ken

Kim Sun Jun 03, 2012 9:49 pm

proctor wrote:Nice one, the one I owned back in the late 70's I flew in a kind
wild stunt. It never missed a beat,a great engine. I seem to
remember it was kind of plated all over, not chrome but a kind
of shiny zinc plate. Would that be right?
Got stolen when all my personal stuff was being shipped to Norway
for a construction job.
John

Yes, sounds right. My Uncle's engine has a dull finish, and I THINK I've narrowed it's production run from 1958 to 1963 using Mr. Dannel's book. My own Fox .35 has the zinc-like finish you described, and though I haven't yet found a specific note saying so, from looking at the photos, it APPEARS that the shiny finish started around 1971-72. I think I got mine in late '74 or '75.

My Uncle's Fox .35 and .29s were (are) his flagship engines, and it was an immense point of pride for him to watch Bobby and me put his Shoestring and Ringmaster through their paces. If someone walked up to him while we were flying, we'd chill for a lap, and watch for his finger twirl signal for us to really lay into our short repertoire of stunts. We didn't understand the concept of running them a bit rich so they could peak during hard pulls. Wayne tuned them to a notch just below full lean, so like your maneuvers, everything we did was FAST !

Sorry yours got taken, but there are apparently a bunch still out there!

Kim Sun Jun 03, 2012 10:11 pm

shawn cook wrote: Kim, I can't say enough about the Fox.35. Your example there is pretty cool. That's a large bypass model circa 1960? with the 35 displacement casted onto the case. My earliest is what I believe to be the 1958 version as mine has no casting web obstructions in the exhaust port. The old Fox.35's can be extremely difficult to install the cylinder head on properly. The case is very thin and can distort easily.
Ken

Yeah, I don't think Wayne's has ever been apart, and the same for my 70's Fox. At this point, I'm figuring on letting the old dog run. I knew that there was a bunch more to there maintenance than might appear. I tried to track down Wayne's engine history, and it looks like it spans from 1958 when the lower webbing appeared, to the 1963 anniversary editions, but the book I have is bit vague on this.

I've got Wayne's Goldberg "Buster" awaiting some silkspan, and I'll see if Wayne wants to reinstall the .35 on it. My Ringmaster S-1 is way down the list of projects at this point, but it WOULD look great with that .35 hanging on it's nose!

Thank you for the notes on this thing...I'm gonna cut and paste them in my engine notes...against the day when I need to open one of these up !!!

**Cribbs74** Mon Jun 04, 2012 9:28 am

Oh to be a kid in the '60's...... I always thought I was born in the wrong era.

The only thing I have to show from my youth is My 'lil Wiz. You truly were a lucky kid Kim, my father was a pre teen in the late fifties early sixties. When I mentioned recently the Cox engines I was after he said "I remember those names, we used to read about them all the time in magazines" he also said they were unaffordable at the time. My Grandmother (single parent) would have never spent the money on frivalous things like engines.

Next time my Dad is in town I would like to re-create our 1977 failed launch of the 'lil Wizard. This time around I would like to get some laps in. Dad is missing a leg these days but, I am sure he would appreciate the sound and smell.

I sure hope you and your Uncle get that .35 in the air where it belongs! Good job, great engine and excellent story! Thanks Kim.

66 Malibu Thu Jun 07, 2012 11:19 pm

Since reader's of this thread probably have an interest or maybe even own some of the Large "off brand C/L engines", I want to ask if anyone may have a Needle Valve Assembly or what have you for a McCoy .35 Red Head?
I got a box of stuff of C/L stuff including Cox stuff at the local R/C Flying Club auction last weekend and the McCoy was in the bottom of the box.After cleaning it thoroughly, it appears to have been used only a few times but the NV was missing.
PayPal is ready or ?
Thanks, Steve.....

Ken Cook Fri Jun 08, 2012 2:30 am

Hello Steve, Mecoa has parts for the next series of Mccoy engines. https://shop.mecoa.com/shopdisplayproducts.asp?id=102
The needle valve assembly is sold in individual parts: spraybar, nut, ratchet clip , needle etc. This is the original unit and the parts do add up. The problem is the quality of the Mccoy redheads were all over depending on when it was made and what type you have.They made a shiny case version as well as a later production run which was the Lightning bolt case which had a glass beaded dull like case.

I've never used the Mecoa spraybar, but they claim it is the same and it's the only part on their listing of the series 21 engine that fit the redhead. A Fox.35 needle will fit the Mccoy with the nut just making it onto the spraybar. I would caution you to use only all castor fuel. I've had these engines wear out in one run. This isn't uncommon if you didn't already know that. Using all castor fuel even with percentages of 29% oil and 10% nitro is a good blend. The piston is claimed to be the culprit and compression can certainly be eliminated in just one lean run. They do have a place in my heart as it was my first "large engine". It's unfortunate though that they can wear out so quickly. I do have some shiny case versions that have been going strong since 1966 though. These engines were sold in a cardboard and plastic blister pack at one time for under $5. You just ran them and wearing them out wasn't a concern if you could get the weekend in to fly them. Ken

Kim Fri Jun 08, 2012 11:33 am

Had a dress rehearsal for Wayne's Sig Chipmunk this morning !

Vibration with the K&B Stallion is dramatically reduced from our run a few weeks ago (probably due in large part to balancing the prop), and it ran out it's fuel. The filter showed totally clean, and other than the Williams Brothers Pilot Head bouncing around inside tthe canopy, she's looking first-rate.

There WILL be video with this one !

fit90 Fri Jun 08, 2012 11:43 am

Looking good. Can't wait to see the video. Looks like you had a great day to work on it, plenty of blue sky.

Bob

andrew Fri Jun 08, 2012 11:51 am

fit90 wrote:Looking good. Can't wait to see the video. Looks like you had a great day to work on it, plenty of blue sky.

Bob

DITTO.

The Wittman Buster shown in Kim's earlier post was my first "large" plane powered with a McCoy Redhead .19 --- I had flown only 1/2A before. I wish I could say that the first flight was a success, but alas ...... I had forgotten to install the outside wing weight. We didn't have any grass on the farm short enough for a takeoff, so my father hand launched it. The inside wing dropped and it headed for a wingover at about 45 degrees. When it hit the end of the cables, it jerked the handle out of my hand, rotated 90 degrees and headed down. It was a complete basket case. My first foray into larger C/L lasted about 4 seconds. Later on, I got a Tom Tom (powered with the same McCoy .19) and flew it until it held more oil than the Exxon Valdez.

Seeing the Buster has stirred up some nostalgic memories of my Dad and early years in the hobby. It just may have to go on my bucket list.

andrew

microflitedude Fri Jun 08, 2012 11:59 am

Ivanhoe wrote:Nice one, Kim, that's a classic engine. Back in the day the Fox .35 was THE engine you yearned for if you flew stunt, trouble was, imported engines were out of the reach of us poor schoolboys, so I, for one, never owed one, even now the only larger Fox I have is a .15, now you have gone and re-ignited my need to own a 35, and I shall be haunting EBay again!

Get thee behind me!

http://www.ebay.com/itm/Fox-35-Glow-Engine-Vintage-Control-Line-RC-Plane-/190688124763?pt=Radio_Control_Parts_Accessories&hash=item2c65e5df5b#ht_500wt_1202

Ivanhoe Fri Jun 08, 2012 12:12 pm

microflitedude wrote:
Ivanhoe wrote:Nice one, Kim, that's a classic engine. Back in the day the Fox .35 was THE engine you yearned for if you flew stunt, trouble was, imported engines were out of the reach of us poor schoolboys, so I, for one, never owed one, even now the only larger Fox I have is a .15, now you have gone and re-ignited my need to own a 35, and I shall be haunting EBay again!

Get thee behind me!

http://www.ebay.com/itm/Fox-35-Glow-Engine-Vintage-Control-Line-RC-Plane-/190688124763?pt=Radio_Control_Parts_Accessories&hash=item2c65e5df5b#ht_500wt_1202

Yes, thanks for that, however as usual.........

Item location: LAKELAND, FL, United States
Ships to: United States

I know I could get someone in the States to have it delivered, but I do not bid on anything "US only" on principle!

microflitedude Fri Jun 08, 2012 12:19 pm

Ivanhoe wrote:
microflitedude wrote:
Ivanhoe wrote:Nice one, Kim, that's a classic engine. Back in the day the Fox .35 was THE engine you yearned for if you flew stunt, trouble was, imported engines were out of the reach of us poor schoolboys, so I, for one, never owed one, even now the only larger Fox I have is a .15, now you have gone and re-ignited my need to own a 35, and I shall be haunting EBay again!

Get thee behind me!

http://www.ebay.com/itm/Fox-35-Glow-Engine-Vintage-Control-Line-RC-Plane-/190688124763?pt=Radio_Control_Parts_Accessories&hash=item2c65e5df5b#ht_500wt_1202

Yes, thanks for that, however as usual.........

Item location: LAKELAND, FL, United States
Ships to: United States

I know I could get someone in the States to have it delivered, but I do not bid on anything "US only" on principle!

If you decide you want to, I can buy it for you and then ship it to you.

Godsey3.0 Fri Jun 08, 2012 12:51 pm

Very nice kim. I am definitley sold on the Fox engine. Love that sound. Easy to tune. Rock solid.

66 Malibu Fri Jun 08, 2012 1:38 pm

Hi Ken,
Thanks for the info and advice re: my McCoy .35. I thought my next step would have to be MECOA since I hate the EBay option to find the part.
The engine is a shiny case unit and not the Lightning Bolt type case that I have seen before.No telling how old it is.
I remember my friend's brother belonged to a C/L Combat Club back in the 60's and they joked that the McCoy .19,.29,and .35's would be worn out when you finished breaking them in !!
I'll eventually get it running and will use your advice on fuel percentages also...
Thanks Much, Steve

shawn cook wrote: Hello Steve, Mecoa has parts for the next series of Mccoy engines. https://shop.mecoa.com/shopdisplayproducts.asp?id=102
The needle valve assembly is sold in individual parts: spraybar, nut, ratchet clip , needle etc. This is the original unit and the parts do add up. The problem is the quality of the Mccoy redheads were all over depending on when it was made and what type you have.They made a shiny case version as well as a later production run which was the Lightning bolt case which had a glass beaded dull like case.

I've never used the Mecoa spraybar, but they claim it is the same and it's the only part on their listing of the series 21 engine that fit the redhead. A Fox.35 needle will fit the Mccoy with the nut just making it onto the spraybar. I would caution you to use only all castor fuel. I've had these engines wear out in one run. This isn't uncommon if you didn't already know that. Using all castor fuel even with percentages of 29% oil and 10% nitro is a good blend. The piston is claimed to be the culprit and compression can certainly be eliminated in just one lean run. They do have a place in my heart as it was my first "large engine". It's unfortunate though that they can wear out so quickly. I do have some shiny case versions that have been going strong since 1966 though. These engines were sold in a cardboard and plastic blister pack at one time for under $5. You just ran them and wearing them out wasn't a concern if you could get the weekend in to fly them. Ken

Ken Cook Fri Jun 08, 2012 2:13 pm

Steve, like I said if you didn't want to go the Mecoa route the Fox needle works. Anyone though that has been into this hobby can tell you though how much of a "POS" needle that goes into the Fox. In regards to fuel. I would never recommend 29% oil in any engine except for the Mccoy. Ken

Godsey3.0 Fri Jun 08, 2012 5:16 pm

I just had an interesting experience. Me and my dad went to fly today and when he tossed it off it was pointed somewhat towards me. The plane immediately tried to tighten the lines up. When it did it jerked the handle right out of my hand. It then started to do a wing over. I saw the handle about 5 feet away and ran for it. I had no clue if it was upside down. I just wanted to tighten the lines. When they did it jerked the handle back out. At this point I was swearing like a sailor. I was sure the plane was a gonner. But miraculously, it skidded to a landing on its own. No better than I could have done. This scared the living daylights out of me. I am still surprised at how much force it had when it jerked on the lines. I had a tight fist on the handle and I still lost it.

Rolla

66 Malibu Fri Jun 08, 2012 5:26 pm

Thanks Ken...I have a Fox .15 C/L w/muffler, a Fox .25 C/L Stunt Special, and a big powerful
"Big Mama" Fox .50BB R/C. I'l pull some of those NV and see what's what. Great advice !!
The 29% Castor I knew was for the McCoy only. I'll mix up a special batch of 15% Nitro 29% castor when I'm ready to go with it.
My friend and I lit up the Fox.50 on his Big Boy test stand attached to his picnic table, and I'd swear if the picnic table had wheels, that Fox would have dragged it all over his back yard !!! What power !!
Steve..

shawn cook wrote: Steve, like I said if you didn't want to go the Mecoa route the Fox needle works. Anyone though that has been into this hobby can tell you though how much of a "POS" needle that goes into the Fox. In regards to fuel. I would never recommend 29% oil in any engine except for the Mccoy. Ken

Ivanhoe Fri Jun 08, 2012 5:29 pm

Godsey3.0 wrote:I just had an interesting experience. Me and my dad went to fly today and when he tossed it off it was pointed somewhat towards me. The plane immediately tried to tighten the lines up. When it did it jerked the handle right out of my hand. It then started to do a wing over. I saw the handle about 5 feet away and ran for it. I had no clue if it was upside down. I just wanted to tighten the lines. When they did it jerked the handle back out. At this point I was swearing like a sailor. I was sure the plane was a gonner. But miraculously, it skidded to a landing on its own. No better than I could have done. This scared the living daylights out of me. I am still surprised at how much force it had when it jerked on the lines. I had a tight fist on the handle and I still lost it.

Rolla

Centrifugal force on a control line model can be very powerful, this is why all competitors under AMA or BMFA rules are required to have a wrist safety strap attached to the handle whenever they are flying, I have seen many C/L models, mostly high-powered combat models when the flyer either looses the handle, or the lines get cut, become unguided missiles, with spectators scattering in panic. The safety strap doesn't prevent the model destroying itself, but it does ensure that it takes no innocent bystanders with it!

Godsey3.0 Fri Jun 08, 2012 5:48 pm

What oil percentage is good for the Fox? On their website they sell it with 29% but they may just be for the Ceramic Liner engine. They also have 18% and 20% Castor.

Another thing I noticed happen today, the fuel tank on my Skyray slid forward and pinched the line against the engine. These made it run peak for about a minute. It would occasionally rich up for about 5 seconds as the tank slid around. Landed it and engine was completely fine. I will not want to do that to it all the time though. I have been flying it just lean enough to keep the engine running. I need to get a sullivan slant tank for it.

My dad also said if I am to fly it in a public setting then I will have to have a muffler. There is another field on our land I can fly on in the meantime though. Anyone know of a muffler that will work? I found the strap from brodak. Just need a corresponding muffler.

Rolla

gcb Sun Jun 10, 2012 1:45 pm

Funny thing about needles, many who run Fox .35's a lot replace the needle assembly with an Super Tigre one.

Fuel: Both Fox and McCoy red heads are iron piston, steel cylinder setups and as such can form a caster seal that will help maintain compression when it would normally be "over the hill". Synthetic lubes run so much cleaner that they will remove this varnish seal and, if the engine is over the hill, you will know it because it looses compression in a run or so. Switching to all-castor fuel will restore a varnish seal after some running.

Additionally, the Fox .35 and the McCoy redheads require more than normal lubrication. Most iron/steel setups, including other Fox engines, require 20%-22% oil whereas these two should have 25%-29%.

One more thing, all Fox .35's since ~1952 can use parts that fit today's latest version.

George

gcb Sun Jun 10, 2012 2:06 pm

Rolla,

Actually, ceramic liners can use less oil. The 18% lube is for larger ABC engines with BB supported crankshaft.

The Fox .35 is a maximum sized engine in a minimum sized crankcase to make it light. Since it also has amall cooling fins, much of the combustion heat is carried away by the lubricant. I think the McCoy's excuse is the material it is made of. In any case, use less than 25% oil and you will probably have a short-lived engine.

Later Foxes have provisions for muffler attachment. For the strap-on, tighten the strap carefully and not too tight. Since the Fox was made light, the crankcase, especially on the bypass side where the strap goes, is very thin and easy to warp. If you can compromise a bit, use a tongue muffler...they are a little less effective but also lighter.

George

Kim Sun Jun 10, 2012 7:42 pm

After a run to Illinois to fly my uncle's Sig Chipmunk, I brought back two more of Wayne's Fox Engines: a Stunt .29 which will reside again in his Goldberg "Wittman Buster" when it's restoration is complete, and a Combat .35 that will fly my late Uncle Bill's Stearman PT-17 after it's turn in the Skunk Works Fountain of Youth !!!

----------------------------------------------------------------------------------------------------------