Club FOX!
#3576
So I'm of the bias that a very low/no run time engine with an ABC or AAC cylinder should be snug. Mine have a pinch but they're easily turned over without a prop; glow plug or not. I'm sure it will run fine and last a long time but likely won't produce the power it's capable of if it had a tighter fit. I'm not complaining mind you. Just adding my thoughts and understandings albeit more limited than others here.
To be fair, your LA engines are in a different class compared to a Fox, IMO.
Last edited by 1QwkSport2.5r; 08-19-2014 at 08:13 AM.
#3577
Regarding the Fox looks, you should check out their newest carb, it is a beauty (and functions perfectly). That might cure your carb needle issues too, Tim. I know it won't be vintage, but you will love the looks and performance with the new carb.
My Fox 74 ring engine also has super high compression that it feels like an ABC. When I flip the prop, you also have to move your finger out of the way or it will get smacked. The 74, according to the article by Clarence Lee that is always quoted around here, has higher compression than the Fox 60. That is why you have to run LOW nitro fuel (5% max) on it. That is even after getting the new head button plus 2 head shims.
I recently had to dump a nickel-plated engine because the liner peeled after an accidental lean run. Some dirt got in the fuel and clogged the carb (my fault of course). While the plane was flying, the carb got clogged and leaned out, causing the liner to peel. I couldn't cut the engine because it was on a plane that cannot dead-stick. There was still some pinch at TDC (less than originally), but as the engine warmed up, the compression is lost, and engine would quit. Normally, I would repair/replace the damaged part, but this brand of engine's spare parts are so expensive, that I decided to switch over to a used 4-stroke glow instead.
My Fox 74 ring engine also has super high compression that it feels like an ABC. When I flip the prop, you also have to move your finger out of the way or it will get smacked. The 74, according to the article by Clarence Lee that is always quoted around here, has higher compression than the Fox 60. That is why you have to run LOW nitro fuel (5% max) on it. That is even after getting the new head button plus 2 head shims.
I recently had to dump a nickel-plated engine because the liner peeled after an accidental lean run. Some dirt got in the fuel and clogged the carb (my fault of course). While the plane was flying, the carb got clogged and leaned out, causing the liner to peel. I couldn't cut the engine because it was on a plane that cannot dead-stick. There was still some pinch at TDC (less than originally), but as the engine warmed up, the compression is lost, and engine would quit. Normally, I would repair/replace the damaged part, but this brand of engine's spare parts are so expensive, that I decided to switch over to a used 4-stroke glow instead.
#3578
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When I say little pinch, the Fox .74 and the LA's, a .46 and a .65 will gently push the sleeve up out of the block but very little finger pressure will hold it down. I know all that is subjective, I had a Zeus .61 that nothing short of having the head on would hold it down. So many variations of our toy stuff.
#3579
H - the Fox parts factory doesn't have any spare parts. Been looking on the auction site for Fox carbs and am coming up empty. I need to .312" carbs for my Twin and I need one for my .46BBRC. The 50BB has an MkX .330" carb on it which might be a bit large for its rev range too.
The MkX carbs are good carbs, this old one has just seen better days. I'll mess with the detents and put some Teflon tape on the needles threads. Should clear up most of the touchy needle problem. The biggest problem with these carbs (MkX) is the coarse threads on the needles.
The MkX carbs are good carbs, this old one has just seen better days. I'll mess with the detents and put some Teflon tape on the needles threads. Should clear up most of the touchy needle problem. The biggest problem with these carbs (MkX) is the coarse threads on the needles.
#3580
H - the Fox parts factory doesn't have any spare parts. Been looking on the auction site for Fox carbs and am coming up empty. I need to .312" carbs for my Twin and I need one for my .46BBRC. The 50BB has an MkX .330" carb on it which might be a bit large for its rev range too.
The MkX carbs are good carbs, this old one has just seen better days. I'll mess with the detents and put some Teflon tape on the needles threads. Should clear up most of the touchy needle problem. The biggest problem with these carbs (MkX) is the coarse threads on the needles.
The MkX carbs are good carbs, this old one has just seen better days. I'll mess with the detents and put some Teflon tape on the needles threads. Should clear up most of the touchy needle problem. The biggest problem with these carbs (MkX) is the coarse threads on the needles.
My only experience with Fox carbs is the new TN carb and the EZ carb. I like both a lot. The EZ carb has been sitting in a baggy for the last 3-4 years and froze up from the castor oil I suppose. But it is still good otherwise.
Bummer about the Fox Manuf. not producing more engines!!! I was going to rebuild an old classic pattern Phoenix 8 plane I bought used and put the Fox 74 in it with a Jett muffler. I wonder if I should just store the engine away for posterity instead.
#3581
My only experience with Fox carbs is the new TN carb and the EZ carb. I like both a lot. The EZ carb has been sitting in a baggy for the last 3-4 years and froze up from the castor oil I suppose. But it is still good otherwise.
Bummer about the Fox Manuf. not producing more engines!!! I was going to rebuild an old classic pattern Phoenix 8 plane I bought used and put the Fox 74 in it with a Jett muffler. I wonder if I should just store the engine away for posterity instead.
Bummer about the Fox Manuf. not producing more engines!!! I was going to rebuild an old classic pattern Phoenix 8 plane I bought used and put the Fox 74 in it with a Jett muffler. I wonder if I should just store the engine away for posterity instead.
I've not used the new TN carb, and I have not ran the .46 with the EZ carb yet either. So my Fox experience is limited to the MkX carb which is an auto-mixture carburetor much like the newer TN carb. I'm not a fan of the butterfly Carburetors on my Twin at all.
#3582
Barring a bad crash, rings and bearings are readily available. Put a couple Bowman rings on the shelf as spares and run the snot out of it.
I've not used the new TN carb, and I have not ran the .46 with the EZ carb yet either. So my Fox experience is limited to the MkX carb which is an auto-mixture carburetor much like the newer TN carb. I'm not a fan of the butterfly Carburetors on my Twin at all.
I've not used the new TN carb, and I have not ran the .46 with the EZ carb yet either. So my Fox experience is limited to the MkX carb which is an auto-mixture carburetor much like the newer TN carb. I'm not a fan of the butterfly Carburetors on my Twin at all.
I received good help on the EZ carb from the guys in this forum when I first got the 74. The instructions say to start with the air bypass set in the middle. Some advocated to try with the air bypass completely shut and that way you only open the least amount of air bypass for idling. That helps with the fuel suction into the carb.
Last edited by hsukaria; 08-19-2014 at 01:22 PM.
#3583
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Ran the little lapped .40 for a bit today. I didn't have much time to run it but got it dialed in almost perfect in that time. I had to swap the original high speed needle back in; the end was too long (and narrower) and required being nearly seated to get it into the sweet spot. The old needle had a shorter and thicker tapered end. It idled happily at 2,500 for as long as I let it, but would tick over nicely at 2,100. It throttles pretty nice, though there is a little false needle setting I'm sorting out. Even with tubing on the needle, it still leaks a bit and allows the mixture to change if I bump it causing the rpm to drop (rich). I think the detent clips need to be tweaked and that should help. I'll run more props on it when I get time. It peaked at 13,750 on a 10x5 and FAI fuel today. Pretty consistent in peak revs given the swings in climate lately.
CR
#3584
#3586
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What kind of pressurization are you running?
CR
Last edited by Charley; 08-20-2014 at 02:25 PM.
#3587
I run regular muffler pressure on all of my engines except one or two (no muffler). Some of my Super Tigre, both K&Bs, and my Enya .30 all leak a little fuel from the needle.. My ST S29 is probably the worst. They do not have O-rings in the needle holders or on the needles themselves like other companies do. At least not on the Carburetors I have.
#3588
I run regular muffler pressure on all of my engines except one or two (no muffler). Some of my Super Tigre, both K&Bs, and my Enya .30 all leak a little fuel from the needle.. My ST S29 is probably the worst. They do not have O-rings in the needle holders or on the needles themselves like other companies do. At least not on the Carburetors I have.
#3589
Some manufacturers use o-rings on the needles and some don't. I assume the engines that don't were designed at point in time where most folks didn't use muffler pressure. Some of the mufflers that came with some of my engines were not tapped for pressure but had the location cast into the muffler for it to be added. The engines that I run without pressure need the needle opened 1-1.5 turns further open; fuel consumption is up slightly. My .60 4-stroke picks up several hundred rpm if pressure is used but I don't have a good fitting muffler for that engine.
Conversely, my RC car engines won't run (even idle!) without pressure. The carburetor on my .28 monster truck engine has a 9.2mm carb choke.
Conversely, my RC car engines won't run (even idle!) without pressure. The carburetor on my .28 monster truck engine has a 9.2mm carb choke.
#3590
Some manufacturers use o-rings on the needles and some don't. I assume the engines that don't were designed at point in time where most folks didn't use muffler pressure. Some of the mufflers that came with some of my engines were not tapped for pressure but had the location cast into the muffler for it to be added. The engines that I run without pressure need the needle opened 1-1.5 turns further open; fuel consumption is up slightly. My .60 4-stroke picks up several hundred rpm if pressure is used but I don't have a good fitting muffler for that engine.
Conversely, my RC car engines won't run (even idle!) without pressure. The carburetor on my .28 monster truck engine has a 9.2mm carb choke.
Conversely, my RC car engines won't run (even idle!) without pressure. The carburetor on my .28 monster truck engine has a 9.2mm carb choke.
#3591
If you use crankcase pressure, I think you need a regulator or check valve or something to prevent the negative pressure pulse from creating a momentary vacuum in the tank, I think?
#3592
Most were on the bottom under the crankshaft port. The port would be open only when the crankcase was under pressure. This produced a lot more pressure than muffler pressure. Most were used for control line and so for wide open throttle only the needle was required, no regulator.
#3593
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I run regular muffler pressure on all of my engines except one or two (no muffler). Some of my Super Tigre, both K&Bs, and my Enya .30 all leak a little fuel from the needle.. My ST S29 is probably the worst. They do not have O-rings in the needle holders or on the needles themselves like other companies do. At least not on the Carburetors I have.
CR
#3598
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"Most people and companies outside of Japan have absolutely no idea what they are. With the similarity in appearance to the Frearson and the Phillips the screws are often damaged in removing and installing with the wrong tools. JIS tends not to camout like Philips. The JIS driver can be used on Phillips quite easily but not reciprocally. "
I've been called a "Feckless Fool" for waiting to obtain the correct screw driver to remove the backplate of my Fox Eagle 60 as the instructions call out the correct tool to use.
This was what I was trying to avoid....
http://www.instructables.com/id/When...rial-Standard/
Last edited by Broken Wings; 08-23-2014 at 12:54 PM. Reason: added link
#3599
I know the wrong tool was used. The engine came to me like you see in the picture. Auction site special! Since the screws need to be replaced, I'll use socket head cap screws instead which are more common.
#3600
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I almost always replace fasteners with allan head cap screws. Makes for a much simpler installation and consistent clamping torque. Ball end drivers make access less of a problem, as well.
I have also found most screw fasteners to be much softer material and easier to damage.
I have also found most screw fasteners to be much softer material and easier to damage.