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My brand new Copperhead .049 seems to be nothing but eye candy junk Empty My brand new Copperhead .049 seems to be nothing but eye candy junk

Post  dragnse7en Sat Oct 29, 2022 8:10 am

Hi there everyone,

At the end of September I snatched up #25 directly from Cox International and was pretty amped to get another high performance engine. Roughly two weeks later, I received it in the mail, unboxed it to check things out and read all the documentation and instructions and then put everything back in its packaging for later.

The instruction manual is in no way different than all the other standard reed valve Bee series engines aside from the upper left on the page indicating that they're the instructions for the copperhead, and mentions there are three glow head gaskets installed instead of one, and recommends removing one and then two glow head gaskets after running several tanks through it.

I couldn't get close to that point, let alone get it broken in.

I've followed the instructions exactly as they read, and the engine has a terrible time. The compression feels noticeably harder than a .049 with a high compression head and sounds like its running harder than expected for the short time that it does actually start. Before the engine decides to quit it sounds like its getting bogged down and I can see the prop slow down just as quickly and abruptly. It refuses to stay running for anything more than 3-4 seconds. A few times after restarting, the engine would run longer, but very weak and slow, making some sort of chugging noise.

Another alarming thing I discovered is that there's an unusual amount of fuel that leaks out of the front end of the crankcase; it's about the same amount of fuel typically seen when an engine runs way too rich or is about to flood out.


This was supposed to be a brand new motor and I really hope that this particular series wasn't produced solely to be non-working collectors' eye candy or a shelf queen relic. I have my share of display goodness of limited edition rc stuff, but engines aren't my fancy to showcase - trust me I've got high performance limited ed. brushless motors for my carpet racers that look better and cost easily well over double the price I paid for the Copperhead engine. Long/ short, I bought this engine to RUN and not sit and stare at it.

The time has long passed by to contact Cox International for a return and doesn't meet their conditions in their policy because I used it and now there are small tool marks on the head adapter from disassembly and cleaning.

At this point I'm going to put a bone in my nose and cannibalize it for parts. It would not be in my good conscious to pass this POS onto anyone else and see them experience the same headaches. There's nothing supernatural about these glow engines and no deep secrets on operating and maintaining them properly. A bad engine is a bad engine.

PS - for all the purists out there, consider the Cox Copperhead .049 #25 officially decommissioned and from hereon out doesn't exist. The certificate is going in the shredder so no one can falsely claim that they possess the engine.

I'm not a fan at all now of that type of head setup because of what I went through, so I'll save the tank, spinner, and glow head cylinder & adapter for a future trade later on down the road, since they're good parts that could be put to good use by someone else.

Sometimes things don't work out. In this case, it was a nice looking motor that had a major defect.

My brand new Copperhead .049 seems to be nothing but eye candy junk 20221026
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Post  Ken Cook Sat Oct 29, 2022 8:47 am

One thing I will say about your engine is that it's nothing more than a glorified Sure Start. I would start by resetting the ball socket if Cox International hasn't already done so. The glow plug on your engine is a Merlin Glo Bee drop in. Al Kelly designed these and has since passed away. These plugs are also no longer available unless Cox International still has some. Al had a daughter which supposedly was searching for a buyer but to no avail nothing in the past several years. Your problem more than likely is the glow head, it requires about 5-6 gaskets and possibly more. This is going to require experimentation. Head gaskets vary considerably and where they came from. Some are .004", some are less which may need double the amount. Until the engine is broken in, I would use a standard Cox plugs until you get a few runs on it. Nonetheless, the Merlin plugs are good but it certainly sounds to me like your experiencing over compression.

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Post  rsv1cox Sat Oct 29, 2022 8:48 am

Wow, nicely put together review.  Sometimes a bummer get's through.  I'm sorry that this one didn't turn out for you.  But, I would still contact Cox International and give them aa chance to make it right.

You sound very knowledgable and I'm sure that you checked the reed and the intake orifices and the tip of the needle.  

Full disclosure, I bought mine as eye candy and shelf queen so I haven't ran it.  But I just checked compression and found it to be in accordance with all others of the series.  Mine is number 72 (my series) I'm sure others will chime in with more comments. Edit - (and I see that Ken did.)

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Post  balogh Sat Oct 29, 2022 8:51 am

dragnse7en wrote:Hi there everyone,

....

Another alarming thing I discovered is that there's an unusual amount of fuel that leaks out of the front end of the crankcase; it's about the same amount of fuel typically seen when an engine runs way too rich or is about to flood out.




1. You may want to hand-check the radial play of the crankshaft in the crankcase by pushing and pulling the prop radially...a cold engine should not let you feel any radial play..when hot, aluminum expands more than steel so some radial play is unavoidable....some crank and case combinations, especially from the later, Estes era, turned out to be rather loose fit and as such, prevent the required seal for the crankcase , necessary for sucking the fuel in and charging the air-fuel mixture into the cylinder. A typical symptom of such loose fit would be the extensive fuel leak in the crankcase nose that you also observed..when the piston goes down and compresses the fuel-air mixture for the timed charge into the cylinder, the excessive radial play between the shaft and case simply shoots the charge out near the prop drive plate. So instead of charging the cylinder, the fuel is lost along the crankshaft radial gap. Only erratic, short runs are expectable with such engine trouble.

With the propeller removed, try and suck the crankcase nose - unless you find it bizarre - to check if there is a sensible leak of air along the shaft.then you "only" need to replace the crankcase.

2. Another issue may be with the mylar reed...I observed with the latest, plastic cap type reed retainers and the mylar reeds, that the latter tends to form a dome, i.e. is out of plane after a lasting storage, which may also contribute to poor crankcase seal and fuel draw.

3. The over-compression, especially with 3 gaskets under the glow head, may be caused by the engine flooded, after the numerous failed attempts to start it.

Sorry if the above are no brainers, but I would start looking into these 3 areas.

Truth be told, the above loose fit (cylinder/piston, crank and shaft) is not rare with engines made later than the late 80-s..I have boxed Black Widows, Texaco, Killer Bee etc NIB engines all made in the mid 90-s still by COX and not by Estes, and their fit is nowhere near as precise as that of older COX engines.. my heart is bleeding to denounce COX products, but I trust and prefer buying and running COX engines made in the 60-s and 70-s, , even if pre-owned, instead of  later ones.
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Post  944_Jim Sat Oct 29, 2022 10:24 am

Too funny...I grew up in Massachusetts, yet never heard of Florence. I had to look it up. I'm originally from Brookline, at the east end of Rte 9.

Sputtering fuel out of the front of the crankcase is what lead me to understand my Golden Bee from chdhood was all clapped-out. I hope you get to run yous. As others have indicated, I believe you are over compressed. I have the same glowplug/head on one of my boys' models. It had always been a bear to start until I changed back to a standard glowhead. Once I knew the engine was actually fine, I re-installed the Merlin plug/head with a pile of head gaskets and reduced the number until the engine ran hot (or shut off like yours does), and added one-at-a-time back in until I was satisfied. Unfortunately, I don't remember how many are in that engine now.

Good luck, and don't give up!
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Post  dragnse7en Sat Oct 29, 2022 9:29 pm

Totally agreed balough. I am not a fan at all of the latest version of crankcases and have never had any problems with the good ol' trusty gooseneck style ones.

I tried using an unused Cox glow head and got worse results - it just refused to start, gushing fuel out from behind the driveplate.

One nice thing this engine had going for it was the TD type cylinder. I think that will go quite nicely on my RR-1 along with its matching piston & con rod so that engine can get a new lease on life.

I guess I know what I want to trade for that glow head adapter, spinner and stunt tank - another gooseneck style crankcase Smile

Lastly, no, I am not going to contact Cox International yet again about this particular problem. I already reached out to them for a complaint about the 3D printed backplate for the Pee Wee .020. The needle valve body inserted was poorly secured and now spins around too easily, and even worse whoever made these either didn't care or knew any better and used PLA for the material. The fuel ate away the entire circular raised lip that seals the reed against the opening. I'm grateful to have caught that in time before those tiny strings and shreds of PLA destroyed my motor. I'd really like to get my hands on the STL file for it so I can correctly print it up myself using nylon or high impact polystyrene (HIPS)
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Post  Yabby Sun Oct 30, 2022 6:23 am

its probably of no use to you now, but i always run a new engine with a standard cox plug head to run in. I would also look at the reed and check its ok. infact I would replace the reed with a steel one at tge start. then with an empty tank and engine free of fuel I would run the engine on prime only. doing so almost splits the problem in two. If the engine makes horrible sounds etc. and doesnt run clean and free on prime only something is wrong foward of the reed. over compression causes many more problems than would be expected. and once the engine runs rough and doesnt burn fuel or exhaust it properly as its not running freely, the efects compound and can appear worse than they are as the excess fuel is raising the compression even further. standard cox glow head, steel reed, empty tank. prime only. i honestly believe that will take you a long way toward resolving the engine run problem.

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Post  getback Sun Oct 30, 2022 6:30 am

Very Happy Pumpkin Very Happy Wait I HAD to stop right there ( With the propeller removed, try and suck the crankcase nose - unless you find it bizarre - ) Too Funny Andrea. lol! lol! I Love This Forum!
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Post  balogh Sun Oct 30, 2022 6:51 am

getback wrote:Very Happy Pumpkin Very Happy  Wait I HAD to stop right there ( With the propeller removed, try and suck the crankcase nose - unless you find it bizarre - ) Too Funny Andrea. lol! lol! I Love This Forum!


Uhhhhh Eric, your steamy fantasies!! Very Happy
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Post  Yabby Sun Oct 30, 2022 7:08 am

sorry Andrea,

but i too was [bleep] myself laughing. lol. haha. no truly, almost worthy of a report to admin for inapropriate post. i mean, to even say, "unless you find it bizarre" . lol. yes says it all. I think that post is worthy of a sticky at top of home page.

great work Andreas!! lol! tongue Beers

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Post  balogh Sun Oct 30, 2022 8:14 am

Sorry guys, blame it to my non-native English!  lol!  I really meant it as a technical advice, and thought it was bizarre suggesting to suck on an engine that may ooze spent castor...we all know the leakage test of reed valves, which is done similarly... But in retrospect, maybe I should have explained it differently..no harm or vulgarity was meant..sorry if found graphic, my apologies Damn!
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Post  rsv1cox Sun Oct 30, 2022 9:33 am

Sorry guys, blame it to my non-native English! lol! I really meant it as a technical advice, and thought it was bizarre suggesting to suck on an engine that may ooze spent castor...we all know the leakage test of reed valves, which is done similarly

That's the way I took it Andras. Anybody ever sucked gas out of a tube to transfer to your car after running out of fuel. Not a pleasant experience. GI's in WW2 did it all the time.
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Post  cmulder Sun Oct 30, 2022 3:21 pm

rsv1cox wrote:suggesting to suck on an engine that may ooze spent castor...

Castor will leave your body quicker then you might want Smile
The methanol is what you do NOT want to ingest.
It causes blindness before you die.

Regarding the "GI" sucking petrol... It contained lead that causes brain damage.
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Post  dragnse7en Sun Oct 30, 2022 5:40 pm

Hi there guys,

Rummaging and carefully picking around my box 'o cox stuff I found the original standard glow head left over from a recent refurbish, and it appears to be a head that's older than I am. It still glows cherry red! Wow these little things seem a lot damn tougher than I expected! I'll take a second, better look at it because as clean as I could get it, it's still rough from centuries of wrenching and I want to examine the bottom face and see if its flat and smooth enough to re-use.

If I need to resurface the face, I was thinking of making a fixture or some kind of jig to make sure I remove a uniform amount of material but before I even attempt that, is there another easier and simpler way to do it instead of my idea?
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Post  balogh Sun Oct 30, 2022 5:45 pm

I would suggest just place it on a smooth surface like a glass mirror and apply some toothpaste on the contact surface. With circular motion and applying uniform downward force you will soon reach the required contact surface quality needed for a good sealing, unless deep scratches have been left by years of bouncing in your toolbox on the sealing face at which I would be surprised..if not abused, these heads will survive a normal toolbox storage..
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Post  944_Jim Sun Oct 30, 2022 9:29 pm

I'd say pop it on the engine and give it a try copper is a particularly soft material. The head gasket may make up for a trashy gasket surface better than you think. Besides, you can always dress the glowhead later if you suspect a leaky joint.
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Post  Admin Mon Oct 31, 2022 2:00 am

dragnse7en wrote:
Lastly, no, I am not going to contact Cox International yet again about this particular problem.  I already reached out to them for a complaint about the 3D printed backplate for the Pee Wee .020.  The needle valve body inserted was poorly secured and now spins around too easily, and even worse whoever made these either didn't care or knew any better and used PLA for the material.  The fuel ate away the entire circular raised lip that seals the reed against the opening.  I'm grateful to have caught that in time before those tiny strings and shreds of PLA destroyed my motor.  I'd really like to get my hands on the STL file for it so I can correctly print it up myself using nylon or high impact polystyrene (HIPS)

I would totally expect the engine to be a runner. I wouldn't hesitate to contact Bernie at Cox International if you are unhappy, even if you bought it years ago. He checks in here from time to time so perhaps he will see this thread.

What kind of crankshaft does this engine use? Can you post a picture? I know Cox International had some loose fit issues with their first run of Killer Bee style cranks some number of years ago. If I recall correctly, they were also a bit too long and required a few thrust washers/shims behind the driveplate. Those weren't available for long though. If fuel is leaking out from in between the case and tank, the crankcase may require some sanding of its surface on a piece of plate glass with some lapping film or toothpaste as mentioned. I'd also check the length of the tank screws with that from another earlier Cox engine that uses an 8cc tank (if you have one). If they are a bit too long, they may be bottoming out in the case and not applying the right pressure on the tank to ensure a good seal.

I know who is involved with producing those 3D printed .020 backplates and will let him know. I believe he used DuPont carbon fiber reinforced Zytel for the backplates.

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Post  balogh Mon Oct 31, 2022 3:09 am

Admin wrote:
dragnse7en wrote:
........

What kind of crankshaft does this engine use? Can you post a picture? I know Cox International had some loose fit issues with their first run of Killer Bee style cranks some number of years ago. If I recall correctly, they were also a bit too long and required a few thrust washers/shims behind the driveplate. Those weren't available for long though. ....


Apart from its loose fit, another visible identifier of those early, aftermarket  KB crankshafts was a small hole drilled in the center of the web, seen from the crank pin side..I had 2 of them, both had their splined shaft end for the prop drive plate even visibly off-center, sending the  prop into a terrible vibration. But as Jacob said, those were soon removed from the stock of Bernie and Matt.

My brand new Copperhead .049 seems to be nothing but eye candy junk 16672010


Last edited by balogh on Mon Oct 31, 2022 3:46 am; edited 1 time in total
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Post  Yabby Mon Oct 31, 2022 3:43 am

balogh wrote:Sorry guys, blame it to my non-native English!  lol!  I really meant it as a technical advice, and thought it was bizarre suggesting to suck on an engine  that may ooze spent castor...we all know the leakage test of reed valves, which is done similarly... But in retrospect, maybe I should have explained it differently..no harm or vulgarity was meant..sorry if found graphic, my apologies Damn!

Hey Andras, I appologise. i should have been more considered and sensitive in my comment/post. I greatly enjoy and appreciate all of your posts and the enthusiasm and willingness to share knowledge and the fact you are doing it coming from a different primary language to those of us brought up speaking english. there was not anything innapropriate or vulgar about your post. Any innapropriateness or vulgarity was with my poorly considered attempt at humour.  I should have known much better as I work for an extremely large USA owned aerospace company and spend a lot of time on conference calls into the states and its not unkown of, for the USA end to go deathly silent and all of the australians are rolling around laughing. Even though both ends speak english sometimes there are quite large gaps in what seems funny and its not just me as an isolated Ausy that has that effect at times, thankfully :-)   Main point is, I think my comment/post was poorly considered especially for a forum that is an International forum ( or any forum for that matter ) with many many non native english speakers from many different countries and cultures that interpret things differently which is quite understandable.

My appolgies Andras.  Hand Shake

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Post  balogh Mon Oct 31, 2022 3:56 am

Yabby thanks but no need to apologize...in fact I also find my post a bit funny but need to respect the sensitivity of members from a wide range of countries, and the rules here are clear regarding the language and content, even connotations of expressions. I have been working with US and other native English  speaker colleagues (British, South African, even Australian) in our international company for many years and know that what some may find funny is frowned upon by others, which is absolutely right in our team of linguistic and cultural diversity.

So thanks Yabby I also enjoy your posts very much as I see you are the same engine and motorcycle fan as I am ( I wanted to say freak but not sure if this is offensive or not? Very Happy )

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Post  Yabby Mon Oct 31, 2022 3:58 am

Lol, thanks Andras Very Happy  No, freak is not remotely offensive Lol. I am probably worse than that. Lol. cheers sunny

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Post  dragnse7en Mon Oct 31, 2022 4:02 am

Admin wrote:
dragnse7en wrote:
Lastly, no, I am not going to contact Cox International yet again about this particular problem.  I already reached out to them for a complaint about the 3D printed backplate for the Pee Wee .020.  The needle valve body inserted was poorly secured and now spins around too easily, and even worse whoever made these either didn't care or knew any better and used PLA for the material.  The fuel ate away the entire circular raised lip that seals the reed against the opening.  I'm grateful to have caught that in time before those tiny strings and shreds of PLA destroyed my motor.  I'd really like to get my hands on the STL file for it so I can correctly print it up myself using nylon or high impact polystyrene (HIPS)

I would totally expect the engine to be a runner. I wouldn't hesitate to contact Bernie at Cox International if you are unhappy, even if you bought it years ago. He checks in here from time to time so perhaps he will see this thread.

What kind of crankshaft does this engine use? Can you post a picture? I know Cox International had some loose fit issues with their first run of Killer Bee style cranks some number of years ago. If I recall correctly, they were also a bit too long and required a few thrust washers/shims behind the driveplate. Those weren't available for long though. If fuel is leaking out from in between the case and tank, the crankcase may require some sanding of its surface on a piece of plate glass with some lapping film or toothpaste as mentioned. I'd also check the length of the tank screws with that from another earlier Cox engine that uses an 8cc tank (if you have one). If they are a bit too long, they may be bottoming out in the case and not applying the right pressure on the tank to ensure a good seal.

I know who is involved with producing those 3D printed .020 backplates and will let him know. I believe he used DuPont carbon fiber reinforced Zytel for the backplates.

Please read up - the engine is leaking from the front end, not the rear.  Please read up. ^

If what you mention is true regarding that Cox knew about these issues and decided to sell them despite those problems, then that will only fuel my anger.  I already shredded the COA that accompanied the motor.  I am am simply moving on because I'd rather be flying than discussing the matter of contacting Cox International, hemming and hawing and beating a dead horse.

#25 is no more - final answer.  Its guts are going to be used to build a different and better Bee style engine, and that's that.
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Post  rsv1cox Mon Oct 31, 2022 8:21 am

You might have carried this a bit to far my New England friend (born and raised in New Hampshire but I'm still a Yankee.)

Cox International and EX Engines are fixtures around here and support this forum in many ways, we would be lost without them. A bad engine got through, don't condem the whole institution.

I hope that the parts from it will help you build an engine that you can be proud of.
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My brand new Copperhead .049 seems to be nothing but eye candy junk Empty Re: My brand new Copperhead .049 seems to be nothing but eye candy junk

Post  crankbndr Mon Oct 31, 2022 9:20 am

I found both 1st and 2nd gen Killer Bee cranks unusable, 1st had bad prop screw threading and 2nd seems way to loose in the crankcase bore. I was chastised many years ago for mentioning the 1st gen. Cox machining was top notch and hard to reproduce. Now factory cylinders are all gone, how are the new reman? Haven't heard a word about them. Also the new aluminum backplates, how were they?
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My brand new Copperhead .049 seems to be nothing but eye candy junk Empty Re: My brand new Copperhead .049 seems to be nothing but eye candy junk

Post  balogh Mon Oct 31, 2022 9:41 am

crankbndr wrote:I found both 1st and 2nd gen Killer Bee cranks unusable, 1st had bad prop screw threading and 2nd seems way to loose in the crankcase bore.    .....

Using my simple Vernier caliper, I just measured an old Bee shaft front journal bearing dia at 5.5mm, and the later aftermarket Killer Bee dia measured at 5.44mm...this latter sensibly plays when moved radially, and the sucking...... uhhhhhm...... blowing test shows easy blow-by along the dry shaft...maybe less when wet..

It may not be by accident that later crankshafts are loose fit and old shafts were spot on...the loose fit tolerance in late production engines may have been  triggered by experimental results of Mouse race or other speed events?

I understand from the Paul Gibbault Mouse Race engine tuning guide (http://www.balsabeavers.com/information/articles/mouse_racing_2016.pdf ),  that loose shafts like those that come with the anodized cases (Killer Bee)  may reach  higher speed, but I am afraid excessive radial gap will create engines that will be hard to start, and/or tend to vibrate....just my 10 cents...( I for one would prefer tighter fit in the crank/crankcase and piston/cylinder bore too, like in the heydays of COX, and let the engine be run in and settle at the best fit, and live for long, rather than having a loose fit sports engine that is a few 10-s of rpm faster for a short life, but will not last long) ...this topic was once already discussed here on CEF maybe a year or 2 ago, and Matt said the new KB aftermarket shaft and crankcase fits will be manufactured tighter than the current ones...
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