propjobbill

Does anyone know where a person can buy some small parts for cox engines? I need things like the gasket between tank and engine block for Baby Bees, and also things like the small sprins in the fuel line tube. But perhaps most inportant would be the very small o-ring gasket that goes between the tank and the engine. I know where to but overhual kits. But is there any place where these parts can be bought seporately. It's been years since I have flow a lot of cox engines. These once were available at most local hobby shops. but not any more. Can you help me?

Thanks in advance
Bill

Big Al-RCU

Hi Bill,
I believe you are correct. The last time I tried to find those items, they were only available in the overhaul kit which I thought was overpriced. Most fellows just make their own. I have found (for me) the easiest way to make the crankcase gasket is to smear a little oil on the back of the crankcase. Place it on a sheet of paper and without moving it, trace around the outside with a sharp pencil. Then punch the screw-holes with a piece of sharpened brass tube, then cut the inside with an x-acto and lastly cut the outside with a small pair of scissors. This is a good time to check the flatness of the crankcase. I use a piece of fine wet/dry paper on a flat surface. Lots of times there will be high spots around the screw holes. The o-ring can be sliced off from an appropriate sized chunk of fuel tubbing. I usually slice off a bunch and then pick out the best ones; it only takes a minute.
There is one item that I don't know how to make or where to buy. That is the new style plastic reeds. Mine are mostly all of the older brass style and several need replacing.
al

Ron Kay

My Feedback: (3)

I am looking for high compression/performance carb, head and parts for my Cox 049's and am having trouble finding them... At one time there was a web site that had a great selection of parts. I was planning on getting a couple of the heads and plugs and stuff but when I got back to the site it's no longer active. The company/site I am after is/was...

COMPETITION MODEL AIRPLANE PARTS
P.O. Box 462218, Escondido, CA 92046
Parts for Cox ½ A Engines
Darrin Albert is the new owner.
Phone: (760) 746-3164 Fax: (760) 745-4584
e-mail: [email protected]
www.CompetitionMA.com

Does anyone know if these guys are still in business and more importantly where can I get the parts I'm looking for?

Ron

DICKEYBIRD

Ron, Larry Driskill at http://kittingittogether.com/ has the Galbreath/Nelson plug adapters for Tee Dees and the Nelson plugs. Larry posts here occasionally and is a great guy. Just don't get in a ukie combat match with him!

Some stock parts are still available from Estes-Cox at (800)451-0339 (Mountain Time)

Good luck!

Ron Kay

My Feedback: (3)

Milt,

Thanks for the information I'll follow up with them later today to see what I need. Looking at the site they have a selection of plugs and I'm not sure which to order.

Do you have you hands on experience with these parts? Any idea what I can expect with the changes? Added RPM? Starting problems? Performance? Better flying? (just kidding hahahahah) etc....

As far as getting into competition with him I think he's safe! The only people who are in jeopardy lately are those on the ground... Hmmmmm!

Thanks again and Happy flying,

Ron[>:]

DICKEYBIRD

I use the Galbreath/Nelson for most all my unthrottled engines and they generally pick up 500 to 1000 rpm plus last a LONG time and are cheap. I think the ones I use are the heavy duty ones. Maybe Larry will see this and clarify. The only caveat I can give is that you have to set the head clearance carefully....usually end up with 1 or 2 gaskets more than you normally run with a Cox head for the fuel & props you like. For me at my altitude with 35%, that's at least 5 or 6 gaskets total. Your mileage may vary.

Larry Driskill

Here is what I have written on my KIT Notes page for the Galbreath head. As for the Nelson plugs, I run both the Standards and the HDs. On control line engines, where idling is not an issue, it appears to be a "six of one, half dozen of the other" issue between the two plugs. I need to ask Henry Nelson for some guidance.

5) With the KT50 Galbreath head on Norvels you may find that running less head clearance (fewer head shims) than you were using with the Norvel plug will result in a power increase over using the same head clearance. I recommend you first install the KT50 with the same number of shims you had been using. If all is well and power is comparable or improved you may want to stay there. If you want to optimize compression you can remove one shim at a time until you get maximum RPM or begin to blow glow plugs or have trouble holding a good needle setting.
If you have been using a Cox plug you may want to add a shim or two when switching to the Galbreath head and then try removing one shim at a time, if you are down on power.

Larry Driskill

Ron Kay

My Feedback: (3)

Milt,

I'm flying unmodified 049 TeeDee single head gasket with hi performance stock Cox glow plug at about 5500' using 15% and getting 16.5K sometimes 17K rpm on a APC 5.7 x 3. My buddy flying a 20 year old COX is running 17.5 - 18K? I think he may have an 051 but can't really tell... All I know is that he consistently runs better, faster and more consistently that I do? Any notions as to what the difference may be?

I'm hoping the new head and plug will even the playing field but still would like to know what the difference between to two engines could be...

Ron

propjobbill

Thanks for all the notes, after reading the 9 page cox engine report a found in another discussion. I found I could lape the tank in as discribed with rubbing compound and eliminate the gasket between the tank and engine block. That worked super great. I also found out by cutting a round flat washes gasket from medium fuel line as described. I can probable solve the small spring probles by using a small piece of fule line connected to a piece of aluminium tubing bent to the curve I need.
[size=5]But I have no idea were I can get more head gasket or how to make them. I would like to know where to get the shems that go between the cylenders and the block.
THANKS Bill

propjobbill

DICKEYBIRD

Kustom Kraftmanship-->Competition Model Airplane Parts (Darrin Albert) were the only sources I've ever found for cylinder base shims and loose head gaskets in quantity for .049's. I've emailed a friend for his source of laser cut copper & brass shims for his hot-rod Pee Wee's he was running a couple years ago. I'll let you know if I come up with anything.

jessiej

Don't Norvel head gaskets fit Cox?

Andrew

Yes

the "other" Andrew

propjobbill

I have no idea if norvel gaskets will fit I don't own any Norvel engines but I will try to buy a few and see. I am looking for a source for the norvel gaskets If you know of a source let me know THANKS
Bill

gcb

Easy to tell the difference: Stock, the plastic part of the crankcase is red. Otherwise, just look at the piston. The .051 has a groove in it so you can tell the difference.

George

Ron Kay

My Feedback: (3)

George,

Is it possible that an 051 can perform that much better then an 049? Can an o49 be converted to an 051?

Ron

Tim Wiltse-RCU

A Cox TD .049/.051 run the SAME. It was a marketing gimick with the whole .049/.051 size for the most part. The groove on a .051 piston is only for i.d. purposes and has no performance valve. Also be careful using Norvel head gaskets on a Cox engine the Norvels are wider/have a small i.d. size. I would think it would interfer with the engine firing. Cox head gaskets are .40cents each straight from Cox( I just ordered a pile of them plus o-ring and tank/case gaskets this afternoon).


Later,
Tim

www.hypercoloranodizing.com

Ron Kay

My Feedback: (3)

Tim,

Just visited your site... How cool is that...

On paper they may run the same but in the field a 20 year old Tee Dee is consistently turning 1K RPM or better then my new Tee Dee?

I was OK until you mentioned the Norvel head gaskets. I had no intentions of using anything other then Cox... Should I consider this as an alternative?

Ron

DICKEYBIRD

W-e-l-l not really a gimmick. Way back in the 50's, the Holland Hornet came in .049/.051 sizes so that the competition free-flight guys could enter 2 classes with 1 airframe by simply screwing on a different engine. The 1/2A class was up to .050 cu. in., A class was .051 up to . 15 (I think) Cox just offered the same arrangement to answer a need that was already there.

Ron's buddy's .051 probably runs better because it's an older one with triple bypass porting and a sweet piston/cyl. fit. You KNOW when you get a good one. They sorta run kinda raggedy-rich while you're sneaking up on the needle setting and then suddenly leap up about 2 or 3000 rpm and absolutely wail. Those cylinders have a really magical fit when hot....low friction yet good compression seal. I wish I knew how to identify that fit with measuring instruments!

Tim Wiltse-RCU

Ron,


It's all about good fitting parts. Plus the old T.D.'s are known for being better than the newer ones!

Take care,
Tim

ZAGNUT

My Feedback: (1)

all the newer T.D.s i've seen only have the double milled bybass ports like the "sure-start" RTF engines while the old ones had tripple milled ports. might also be some other diffs like cylider taper but i've never checked.

Andrew

Visit the NORVEL site catalog: www.norvel.com

Head gaskets for the NORVEL and COX will interchange. See for source:

http://www.shopatron.com/product/pro....259.261.0.0.0

Tim W: The gaskets I pulled from a COX product engine and one of my Big Migs were essentially the same. I will put a mic on them tonight and get some exact measuraments.

the "other" Andrew

Tim Wiltse-RCU

Andrew,

That's cool. The head gasket on my older Norvel .049 has a smaller i.d. But then again it's the old model though.

LAter,
Tim

Andrew

Hi Tim --

I pulled some measurements from a couple of NORVELs and 2 COX's -- I make no claims to complete accuracy, but made an attempt to be as consistant as possible across the 4. Here's what I found:

NORVEL Big Mig .049............ID: .416 OD: .500
AME .061...........................ID: .417 OD: .500
COX Product eng.................ID: .417 OD: .502
Black Widow.......................ID: .416 OD: .499

The COX gaskets appeared to be slightly cleaner cut.

The Big Mig is one of the last AAN's and the AME is AAO. The product engine was one of the later models with plastic backplate, aluminum needle valve extension and larger exhaust ports -- this one had the flame suppressor screen. The black widow is about 18 years old and was replaced this summer with a Big Mig .061 C/L. I ran the p*** out of the black widow and it sometimes would not hold a needle setting for a full flight. The NORVEL gave a significant increase in power plus nearly tripled the flight time with a 1 oz. tank.

I did drop the NORVEL gaskets in the COX engines and it appeared that there was sufficient clearance. You're right in that a smaller ID could interfer in the COX. Ed Stevens noted in another thread that the gasket shoulder in the .061 is more narrow than in the .049 -- since the .061 is the major seller, they have likely redesigned the gasket to better fit the .061.

Regards,

the "other" Andrew