need help cox motor
 

Ihave a real old cox motor that i am sure that has never been ran I am trying to start it i got fuel hooked up and power and I am trying to turn it over but for the most part I get nothing every once in a wile I hear a pop pop pop but that is all.
Is there anyone that can help me??????
thank you kyle</p>

RE: need help cox motor
 

Do you have numbers (model, size, and so on... whatever you have) for this engine? There should be enough old-timers around that can help.

CGr.

RE: need help cox motor
 

it been years since I used one but I'm thinking your talking about a spring start, reed valve, .049?

it's usually about 2.5 turns out on the needle and they like about 30% nitro. The thing is getting the needle right and a real good wined on the starter. Give it little prime by putting some fuel in the exhaust slits. If ya flood it unscrew the head and pour out the fuel.
Every cox 049 I ever had was a total pita to start the first couple times while trying to find the right needle setting. Ya just gotta be patient with em. Once ya get them going there almost bullet proof.

RE: need help cox motor
 

check the 1/2a forum above this forum.does the glow plug glow bright orange?as stated above 2 1/2 to 3 turns open is a good starting place for the needle valve.good luck

RE: need help cox motor
 

OK IF I TAKE OFF THE HEAD THE GLOW PLUG YOU CAN SEE IT GLOWING RED HOT I AM USING 25% NITRO FUEL AND I HAVE BEEN TRYING TO START IT WITH THE NEEDLE 2 1/2 TO 3 TURNS OUT BUT I DON'T HAVE THE SPRING THAT THIS MOTOR CAME WITH IS THERE ANY THING ELSE THAT I CAN USE TO GET THIS MOTOR STARTED OR IS THERE ANY WHERE THAT I CAN GET THE SPRING?
THANK YOU KYLE

RE: need help cox motor
 

It is likely that the reed is stuck (presuming it is a reed valve engine). For non spring starting, get a leather glove. Head prime, turn the prop backwards to vertical, attach the battery, and hit the prop forward with a gloved finger.

RE: need help cox motor
 

should glow orange if it is red your battery is getting low on voltage.give a squirt into the exhaust ports even if the reed is stuck it should do more than just pop.it should scream for a second then die.

RE: need help cox motor
 

i had the same issue, i have a cox .049. what i did was turn the rubber stopper in my electric starter backwards and went to town. when i got it running that little guy sang the most beautiful song.

RE: need help cox motor
 

ok it is a cox 049 i can't figure out why I am just geting a pop and not getting any revilushons I think that it might be fluded but I am not sure I will play with it more tonight or tomoro night and get back to you.
thank you

RE: need help cox motor
 

Is it a reed valve engine or a tee dee with a venturi in front of the cylinder. Most of the reedies will have a built in tank with the needle valve protruding from the rear cover of the tank. Is this what you have?

If so you need to ascertain how the tank pickup has been arrainged. Those tanks do not have a clunk and the pickup line is bent almost ninety degrees with a spring inside. This tube can be orriented in four directions and it must be positioned properly depending on intended use.

For Freeflight or RC with the cylinder upright the tube must go to the bottom of the tank For the same situation but a sideways mount the tube must be positioned to go to the bottom of the tank. If the cylinder is inverted then that tube must be pointing to the bottom of the tank.

For controlline use the that pickup must be always arrainged to the outside of the circle whichever direction the cylinder is mounted.

Its possible you are trying to start it with the pickup line at the top of the tank. You need to remove the four tank screws and open the venturi/back plate up to check the pickup orientation.

John

RE: need help cox motor
 

It's also possible that an old Cox engine is too gummed up or too tight to turn over easily. The symptom will be just a pop once in awhile instead of at least burning off the prime with a 1 second run.
If the engine is "free" enough to run, the prop should dance back and forth with a gentle flick.
These engines were sold by the millions to beginners and are some of the worst engines you could ask a beginner to run and try to keep running well for the long haul. There are so many little nit-picky things internally that can keep you from getting it to run well or to run at all.

Be sure to run 25% oil with at least some castor oil involved.

RE: need help cox motor
 

<span lang="EN">

I remember flying U-control with the .049, if you remove the fuel tank you will see a screen filter check that. Also I remember if the engine was out of fuel a squirt into the exhaust port would run the engine for about 3-4 seconds at a fairly high rpm. Also hold the prop. tightly and turn it until you feel it kick now try to start it.</p></span>

RE: need help cox motor
 

my motor does not have a gas tank bilt in.... combatpigg i am running 25% nitro and i still can not get it i think that the carb is just to far gone... it seems like i can not get any fuel in but once i do it is fluded and it does spin freeley
thank you kyle

RE: need help cox motor
 

Oil and nitro aren't the same. Take it apart like JohnBuckner said. the carb isn't really a carb, it's just one needle valve and two ports (a fill and a vent). You probably do have a tank, it's the rounded thing behind the piston and head and stuff.

RE: need help cox motor
 

<span lang="EN">

I remember these so well when I was a kid, try this close the needle valve, squirt some fuel in the port and start flipping the prop. if everything is ok the engine will run for 2-4 seconds. Check that you have a copper gasket on the head also these engines are very sensitive to cold try heating the engine this will make it easier to start.</p></span>

RE: need help cox motor
 

Get rid of it. If you want to get into the air choose some other power system. In fifteen years of club activity I only saw one modeler who could get them to start reliably. If you want piston power go up to an OS.10 engine and it will start and run as easily as the bigger engines. And if you want to stay with a small model, electric is the way to go.

RE: need help cox motor
 

I have to disagree with the unreliable and difficult to start comment.

I have had many Cox engines and providing they are not gummed up with castor residue they are easy to hand start. Just prime them through the cylinder slit and away they will go. The only ones that need the springs are the 020 and 010 sizes.

I bet your reed valve is stuck. Submerge the engine in fuel for a few days and then try again.

RE: need help cox motor
 

Part of the problem here is we don,t even know if it is a reedy. There are litterly hugh numbers of varients of the Cox .o49 that were indeed produced in the millions and they can work but you need to communicate. Post some good pictures of what you have.

After listening more I am inclined to agree with j.lunker and suspect a stuck reed which is very simple to clean but we really don,t even know if you have a reed. There were two types of reed the stamped brass reed in a star shape and a plastic one. The brass one did seem to stick quicker than the plastic type.

Ok if it does not have a built in tank there were some versions (though not in the same numbers) without but the majority of reed engines without tanks were called product engines. They were never sold as such individually but made up in many combinations of components for a specific product (airplane, car, boat, helicopter) with a separate tank.

Next question is, if it does not have a built in tank what arraingement for have you setup for a tank (fuel supply) and how far is it from the engine?