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Need help IDing this engine..
I'm pretty sure its a .40 or .45 but I know very little else about it. I'd like to know the brand if anyone recognizes it. From what I can tell, it looks to be an ABN sleeved engine - No rings or oil grooves. Bore is .835" and stroke .716" (approx.) It has 1 ball bearing in it, and the carb is about 7.2mm. Square flange going into engine block. Backplate held on by 6 screws, which acts as one of the internal ports.
http://i153.photobucket.com/albums/s...R/IMG_0125.jpg http://i153.photobucket.com/albums/s...R/IMG_0126.jpg |
RE: Need help IDing this engine..
Fox 40,
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RE: Need help IDing this engine..
Yup! Says so on the mount. Note that the head is askew. Fins should align with the slipstream, i.e. fore and aft.
Mike |
RE: Need help IDing this engine..
It appears to be missing a screw on the backplate also
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RE: Need help IDing this engine..
I don'tnow about Fox, only have an old 35, but if the engine is cross flow and baffled, then the head turned might cause the baffle on the piston to hit part of the head instead of entering into the groove for the baffle in the head. Or, did Fox use a head button that could be properly located even if the head itself is rotated?
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RE: Need help IDing this engine..
This one is Schnurle ported
With a bushing in the front, you need to run a good bit of castor oil in your fuel You can add drug store castor to your fuel to see how the engine runs and how you like it? If you decide to use it, you can buy some castor oil from onje of the fuel manufacturers or from Sig. |
RE: Need help IDing this engine..
The head is off because I had the head off and just put it back on that way - the engine needs to get torn back down and cleaned thoroughly before I plan to run it. The head will go on the right way when I get it back together. The backplate is in fact missing a screw - the boss for the screw is busted off. I put some JB Weld on it to make a new boss and just need to find a screw to fit. This engine does use a head button, and I did happen to find "40" on the top of the engine mount which I didnt notice before.. I just didnt know the manufacturer of the engine. So if this is in fact a Fox 40, a few questions.. Is it worth a snot, or is it a crappy engine? Is it supposed to make decent power? If I use it, It'll be going onto a Airboat. I also have a K&B Sportster .65 NIP that I will probably use first. I plan to run 5% nitro / 22% oil in either of these engines.. hopefully my LHS has some plane fuel with all castor in it. This seems to be the ticket from what I've been hearing.
Thanks to all that responded.. Now that I know what I have, I can do a little more digging. Anyone know about how old this thing is? Looks like it should be 1975-1986 roughly.. |
RE: Need help IDing this engine..
This Fox 40 was a good engine.
I would say that it was a mid eighties engine just looking at it. They made this engine for several years |
RE: Need help IDing this engine..
ORIGINAL: w8ye This Fox 40 was a good engine. I would say that it was a mid eighties engine just looking at it. They made this engine for several years Thanks for all of your help, guys... Looks like I should be able to swing a 10x6 prop at 12,800rpm give or take... Are these Fox's similar to K&B in they are slower spinning engines? |
RE: Need help IDing this engine..
While I am a Fox engine enthusiast, I am not a Fox engine expert. With that said, I never heard of a single ball bearing Fox engine before. Was this sold to we modelers? Or was it something for the US Government?
Ed Cregger |
RE: Need help IDing this engine..
I've never heard of a Fox or a K&B that was intended to be a slower running engine, although the K&B .65 is quite good at swinging large propellers slowly and powerfully.
Ed Cregger |
RE: Need help IDing this engine..
youll need a pressure fitting too( fuel nipple) looks like the engine has potential....take it apart for us so we can see the inides :)
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RE: Need help IDing this engine..
1 Attachment(s)
Bib brother Fox 50
Hmm file mixup thats my wolf not my Fox 50 will have to try this again martin |
RE: Need help IDing this engine..
ORIGINAL: NM2K While I am a Fox engine enthusiast, I am not a Fox engine expert. With that said, I never heard of a single ball bearing Fox engine before. Was this sold to we modelers? Or was it something for the US Government? Ed Cregger Thanks guys! I'll post back within the next hour or two. Tim |
RE: Need help IDing this engine..
Here is a few snapshots.. It hasnt been soaked and cleaned yet... This is pretty much how I received it. There is a retention screw missing on the carburetor, and the nipple on the muffler is missing but I think I have a spare nipple laying around.. otherwise I'll hit the LHS since I need nitro for my LST's anyway.
http://i153.photobucket.com/albums/s...IMG_0140-2.jpg http://i153.photobucket.com/albums/s...R/IMG_0134.jpg http://i153.photobucket.com/albums/s...R/IMG_0135.jpg Its hard to see in the picture, but there is still hone marks in the crankshaft race. http://i153.photobucket.com/albums/s...R/IMG_0136.jpg http://i153.photobucket.com/albums/s...R/IMG_0137.jpg http://i153.photobucket.com/albums/s...IMG_0139-1.jpg Not 100% perfect condition.. there are knicks and dings on the outside of the engine, but I think it will clean up nice and hopefully run halfway decent. Whats the best thing to soak these things in to clean all of the old castor off? I have some Denatured Alcohol which I was planning to use... Either that or I have some heavy duty "Gunk" Carb cleaner. |
RE: Need help IDing this engine..
Very good pics.
Dawn Power Dissolver will clean a lot. About 45 minutes is the longest everyone says you should leave it on aluminum. I like soaking in a crockpot with antifreeze for 10-12 hours. Don't put the crockpot back in the kitchen. |
RE: Need help IDing this engine..
ORIGINAL: blw Very good pics. Dawn Power Dissolver will clean a lot. About 45 minutes is the longest everyone says you should leave it on aluminum. I like soaking in a crockpot with antifreeze for 10-12 hours. Don't put the crockpot back in the kitchen. |
RE: Need help IDing this engine..
On just a quick rip over the thread, I didn't see a comment that may be needed:
Make sure whether this is an ABC or iron in steel piston/sleeve engine: a small magnet will pull to the iron&steel... I doubt it is ABC, because of when it was likely made. If iron-steel, it will benefit from a fuel with significant castor oil content, particularly in early running. Messy, yes, but very suitable for iron-steel... After it loosens up and starts to feel right, it may be happy on a fuel with 22%-25% oil, at least half of which is castor. And, yes, Fox did make a single BB schnuerle 40 in the late 70's/early 80's - this appears to be one of those. As mentioned, it will probably be happier unloaded on a light prop load. Not as likely to prosper at low RPM/high load on a large diameter prop... Notice in the front view of the case?- the front end of the shaft runs in the aluminum case; no bronze or other bearing shell. That can cause a bit of dark oil weepage, from wear on the aluminum. Shouldn't be of serious concern, just another juicy aspect of a plain aluminum bearing out front. OBTW, all the case screws are 4-40, except possibly the carb and muffler mount screws. It looks like the repaired backplate mount bolt boss you repaired was the one on the case, just above the mount lugs, on the side away from the exhaust? Neat job! The stock Fox muffler is not very quiet, if noise is a problem in your area. Enjoy! |
RE: Need help IDing this engine..
ORIGINAL: Lou Crane On just a quick rip over the thread, I didn't see a comment that may be needed: Make sure whether this is an ABC or iron in steel piston/sleeve engine: a small magnet will pull to the iron&steel... I doubt it is ABC, because of when it was likely made. If iron-steel, it will benefit from a fuel with significant castor oil content, particularly in early running. Messy, yes, but very suitable for iron-steel... After it loosens up and starts to feel right, it may be happy on a fuel with 22%-25% oil, at least half of which is castor. And, yes, Fox did make a single BB schnuerle 40 in the late 70's/early 80's - this appears to be one of those. As mentioned, it will probably be happier unloaded on a light prop load. Not as likely to prosper at low RPM/high load on a large diameter prop... Notice in the front view of the case?- the front end of the shaft runs in the aluminum case; no bronze or other bearing shell. That can cause a bit of dark oil weepage, from wear on the aluminum. Shouldn't be of serious concern, just another juicy aspect of a plain aluminum bearing out front. OBTW, all the case screws are 4-40, except possibly the carb and muffler mount screws. It looks like the repaired backplate mount bolt boss you repaired was the one on the case, just above the mount lugs, on the side away from the exhaust? Neat job! The stock Fox muffler is not very quiet, if noise is a problem in your area. Enjoy! |
RE: Need help IDing this engine..
Good pics.. :) There are no fault with bearing in fronthouse (aluminium bearing), the marks are honing marks to fit the crankshaft, a little sloppy bearing are nothing to be worried so long the crank case compression are good, castor oil will help to keep tight against air leakage in crank case. I doubt the engine are a ABC engine as i can see the engine are a old "Iron" engine since the pic are showing the steel sleeve and cast iron piston. Use pure castor oil between 20% and 25% in fuel (syntetic oil will kill your engine in a short time). There are the FAI fuel available, it has 20% castor oil and 80% methanol to run your Fox engine.
Hope we see your engine are running in Youtube after you has fixed your engine :) |
RE: Need help IDing this engine..
ORIGINAL: Motorboy Good pics.. :) There are no fault with bearing in fronthouse (aluminium bearing), the marks are honing marks to fit the crankshaft, a little sloppy bearing are nothing to be worried so long the crank case compression are good, castor oil will help to keep tight against air leakage in crank case. I doubt the engine are a ABC engine as i can see the engine are a old ''Iron'' engine since the pic are showing the steel sleeve and cast iron piston. Use pure castor oil between 20% and 25% in fuel (syntetic oil will kill your engine in a short time). There are the FAI fuel available, it has 20% castor oil and 80% methanol to run your Fox engine. Hope we see your engine are running in Youtube after you has fixed your engine :) Is it possible to still get Piston and Sleeve sets for this old Fox .40? If so, are they the same type of construction or do they have the option for ABC sleeve & aluminum piston? Are there advantages to the ABC over the Iron/Steel? I am not real familiar with the Aircraft RC realm as I've been a ground-based smallblock and big block ABC engine guy for the past 12-13 years. I'll post pics of my "Kamakaze" airboat build that I'm working on to put my k&b .65 on. Thanks to everyone that has posted! I really appreciate it. |
RE: Need help IDing this engine..
You need to call Fox in Ft Smith and find out about the spare parts?
Fox Manufacturing Address: 5305 Towson Ave. Fort Smith, AR. 72901 Country: United States of America Phone:479-646-1656 Fax: 479-646-1757 |
RE: Need help IDing this engine..
ORIGINAL: 1QwkSport2.5r Is it possible to still get Piston and Sleeve sets for this old Fox .40? If so, are they the same type of construction or do they have the option for ABC sleeve & aluminum piston? Are there advantages to the ABC over the Iron/Steel? Thanks to everyone that has posted! I really appreciate it. I has maked spare parts to my model engines who are out of production. w8ye gave you adress to Fox Mfg, hope they has spare parts to your engine. :) Are there advantages to the ABC over the Iron/Steel? |
RE: Need help IDing this engine..
Back in the good old days (If you care to call it that) I flew many hours on model engines with iron pistons and steel sleeves before ABC technology was utilized
The Foxes, seemed like they would never wear out. |
RE: Need help IDing this engine..
Fox appears to still have this engine. There are no details in the post but looking at the other Fox 40 offerings, this one is much like your engine. The picture looks like a BB engine but they mention nothing about BB or ABC or ringed for this engine.
ttp://www.foxmanufacturing.com/index.php?main_page=product_info&cPath=143& ;products_id=290 |
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