Why won't my tee 049 run properly

I've seen badly distorted head shims and poorly fitting glow plugs responsible and diagnosed as worn out piston cylinder fits more than once. Ken

Hi Ben.
If there's a noticeable resistance and pop as you turn it over by hand, the compression is usually good. Some will not feel as strong when hot, but there should still be some resistance when you pop it over. Whatever it is, it's simple. Tee Dees are much less finicky than Bees with a built-on tank. If you're familiar with the .049 Babe(and other) Bees, the cold compression pop-over feels about the same.
Rusty

Yes I'm very familiar with babe bees and bumble bees and never had an issue with any of them but compression feels the same on the tee dee as the baby bee or maybe marginally higher at all temperatures. The ball socket has a Tiny tiny amount of play it my baby bees had a lot of use and the ball socket on that is very loose but spins a 6x3 at a very reasonable rpm and starts first few flicks.

Someone mentioned that its probably something simple, i thought of battery's.
I use double a batts and they don't last long so what kind of batts do you people use because when i think a batters flat i try it on my flyer engine that starts right up.

Soon i may be going to my local model shop that's Steve Webb models so whats the best fuel to buy from them for all my cox 049s.

Hi Ben. I'll give you my   ... Although I've never owned any Tee Dee's, I've read some about them here on the forum. You want a glow-fuel with 25% minimum nitro content (which is always marked on the bottle) What isn't always listed (and should be..) is the oil content, type.. and mixture. Castor oil in the mix is a MUST. If it's a 50/50 mix of castor/synthetic.. it is perfect. If "Steve Webb Models" stocks "Sig Champion 25"... buy some. Alternatively; if they stock other fuel with the same ingredients as Sig Champion 25... that should be fine. Don't get talked into buying anything different.. and absolutely DON'T buy the Cox fuel that Tower Hobbies sells..

Use "D" batteries.. not the "AA's" that you've been using... A hard starting engine will suck the life out of AA's within minutes of priming and flipping repeatedly with no results... and this compounds the problem further. Any battery will always last longer if you disconnect it when it's not needed. In other words; don't leave the glow-plug clip connected to the plug while you're fishing through your flight box.. or checking anything else outside of flipping the prop to start the engine. The plug draws about 3 amps of current when connected to the battery.. which is a LOT. "D" batteries have more capacity than AA's... and will last much longer. Remember that it takes 1.5V to light the plug. If you use more than one battery; connect them in "parallel" (+ to + and - to -) which doubles the capacity per cell.. but the voltage remains the same. If Steve Webb Hobbies stocks a 1.5V "hobby battery".. (which looks like a lantern battery) you might want to buy one. One is all you'd need with those.. because they have a high capacity.

Good luck!

A properly connected glo and battery combo will give the glo element a distininct a red-orange coloration.

What more need be said? Fiddling with something less and you'll have starting problems.

  

SD

Copper contacts, wires and connections are a must too. I had a brand new battery box with chromed steel contact springs and it wouldn't emit a visible glow. I switched to copper leaf springs contacting the batteries and it worked great for weeks of use. Soldering where possible is a plus too. The heavier the wire gauge, the better it works.
Rusty

Hi Ben , I think with all the input you have you can do it , the right fuel and voltage that everone has spoken of, should put you in the to rpms you are looking for. Where is your location? u may even be closer than you think to on hands help Good Luck, Getback 

I live in north wales by Wrexham in the uk just so you know.

I shall try to get some d Batts and see how I go from there.

Monky (monkey?):

Key your problem solution is to respond to the suggestions made on the forum rather than to remain mute as often is the case.

We are are,after all, hobbyists ourselves NOT professional problem solvers.

SD

Well hello all.

I just came to inform you all that i got it to run,to full revs,very low revs and its easy to start. After just tinkering with it, it just ran.

But all is not perfect as i am getting a tone of reserdue and its dark silver in collour and often osalates on starting.

Basicly when it runs, it runs well and starts easily when its warm but when its cold and over primed (as is easily done with this engine) it runs and stops, coughs and splutters , osalates and runs backwards but ingage a starter moter for a split second and its away.

I think a nother head shim would do the trick but will see what you guys think,but I'm really confused about the reassure issue.

Yea, Mad Monky, at least it's closer than it was.
You can get starter springs for those. It helps until you get the hang of cranking, but it likes to eat the spring occasionally too.  

Oscillating is always from being too wet. If your tank is high enough to gravity feed while the engine isn't running, you may want to put a pinchoff clip of some sort on the line. Then to crank, let fuel feed up to the engine, clip it, prime it, flip it, and when it lights off, unclip the line while the prime is burning off. If it does get flooded, pinch it off and keep flipping until the flood is completely burned off. Then start over.

If you're seeing metal in the exhaust, run it sloppy rich a few times and let it clean itself out, then maybe you can peak it and hopefully it will run clean. If you turn the needle past peak and too lean, then it will shed metal too. Once you come out of the wet "4-stroke" sound and hear a solid steady 2-stroke, that's as fast as she'll run with that particular prop/fuel/etc.

We definitely need to find out why it's bleeding metal. Do you feel any appreciable side-to-side play at the prop end of the crankshaft? There should also be a slight amount of front-to-back play, make sure there is some there. Any stiffness when you turn it when cold? Double check and make sure the prop is reasonably balanced, at least so it'll hang with the blades horizontal. Don't sweat the small stuff though.

I'll think more about it and post back this evening.
Rusty

If you are using a starter to fire up the engine then you will force back the crankshaft against the crankcase backplate. This results in the residue that you are seeing. It clears but then gets worse because the propeller driver will also wear against the crankcase.

Take the backplate off and examine it for scoring. It is not the end of the world for the engine but I would recommend using shims behind the prop driver to prevent this happening or getting worse and keeping the crankshaft seated in the correct position.

I have done this to a few TDs and replaced the backplate and the propeller driver.

Thanks i really appreciate the help.

As for the metallic looking reserdue, i did in fact put some on my finger and rub it and I can't feel any bits and it felt slippery so its lubricated. It was filthy rich when the reserdue was coming out and noticeable i noticed it was a dark silver and didn't change much as i leaned it out, except less reserdue. To me this it a combustion issue or because it hasn't run for a while its clearing out but i will run it again tomorow ant pay more attention to the resardue and see how it goes as i keep running it rich

I have no real idea whats happening so am totaly reliant on you guys to tell me if its safe to run.

I think i can start it now by flicking it so i will just see how it goes

If none of what I asked about in the last paragraph of my most recent post is wrong, then it's probably just cleaning itself out.
The drive plate on Tee Dees equipped with a starter spring can rub the spring and cause a scary metallic residue that means nothing bad. I don't think you have a starter spring, do you?

Please tell me if there is any side-to-side or front-to-back play of the prop shaft. And how much of each. I can only guess so much without some feedback to my questions.
Rusty

Another possibility is loose engine mount screws.

Cribbs74 wrote:Another possibility is loose engine mount screws.

Yes, a real oversight on my part. Thanks, Ron.
Rusty

No biggie, I have been down that road before.

Oh wait a minet i don't know how to remove the back plate could someone help.

I don't mean to sound stupid but what does side to side play in the prop shaft mean and how do I measure it.

When engine is warm its so easy to start but when its cold it has lots of excess fuel in the engine but the more i run it the easyer it is to start from cold but what hight sould the tank be because as soon as its primed it is flooded but at least i can start it by flicking it. I no longer see a metallic reserdue so it must have been clearing out.

Could someone pls tell me the performance of of the tee dee 049,on a 5x3 prop and 25% nitro fuel.

I can't get my head around it but the more i run it ,it turns over smoother and am getting a better compression seal just so you all know i am using optifuel car wich is 15% synthetic add 10% castor and am assuming its safe so can i use it or not.

"Could someone pls tell me the performance of of the tee dee 049,on a 5x3 prop and 25% nitro fuel." - monky

20K RPM or slightly better IF the engine is in good condition. Yours isn't if it's showing aluminum particals in the exhaust. Where did you get it? New,'used?

But just how important is top RPM to you?

SD

mad monky wrote:Oh wait a minet i don't know how to remove the back plate could someone help.

The appropriate Cox wrench for you engine displacement works well if you use MILD heat too.

SD

mad monky wrote:...what does side to side play in the prop shaft mean and how do I measure it.

Grab the prop and try to wiggle it back and forth. If it has any play the bearing is worn and could be the source of metal. Sounds like that problem is clearing up now.

Front to back play is the same thing, just pull and push on the prop and see if it moves. It needs to have some play. If not, when the engine heats up and the Parts expand it can bind causing the engine to slow or shed aluminum. If there is too much play a drive washer can be added to take up some space. Most engines have at least one of those behind the drive plate. It can be measured with a leaf type feeler gauge, but unless you're performance tuning, don't worry about the size of the gap.

mad monky wrote:When engine is warm its so easy to start but when its cold it has lots of excess fuel in the engine but the more i run it the easyer it is to start from cold but what hight sould the tank be because as soon as its primed it is flooded but at least i can start it by flicking it. I no longer see a metallic reserdue so it must have been clearing out.

If you clamped the line as I suggested, then it can't flood from siphoning. Add a bit of fuel to the exhaust port(with the piston blocking it), plus a drop or two in the venturi, it will start to burn that prime on the first flip or two if your glow plug is properly lit. While it's running on the prime, unclip the line and it will run. No flood. If it does flood, follow the routine I posted yesterday to burn it off before trying again.

To help prevent gravity siphoning, place the tank so that the internal pickup tube is level with the needle valve. Clamp the line while you fill the tank so it doesn't force fuel into the engine. You can lower the tank, but then the fuel may drain from the line, starving the engine before you get it cranked. And use as short of a length of fuel tube as possible. No more that a couple of inches.

mad monky wrote:I can't get my head around it but the more i run it ,it turns over smoother and am getting a better compression seal just so you all know i am using optifuel car wich is 15% synthetic add 10% castor and am assuming its safe so can i use it or not.

It's getting cleaned out and loosened up. In the future when you buy a used engine, disassemble and clean it before ever trying to crank it, and this will make it easier, plus it will reduce the stress and wear of fighting the gummy residue on the rotating parts. Maybe one of our English buddies can tell you the best place to get some Cox wrenches.

Cox engines need 17-20% oil, half of which Must be castor. Any less castor and it will overheat and eat itself alive. The Optifuel you describe is still low on castor, so I wouldn't recommend running it fast and lean for any length of time. Remember in one of my first posts, the castor is necessary to lubricate the piston rod ball socket, the most critical point in the rotating assembly. If you want a 50/50 oil mix with that blend, you are going to end up with 30% total oil. That's a bit much for decent performance, but at least it won't kill it.
Rusty

mad monky wrote:

Could someone pls tell me the performance of of the tee dee 049,on a 5x3 prop and 25% nitro fuel.

Hi, Here some links to period press articles with performance figures and graphs:

http://sceptreflight.net/Model%20Engine%20Tests/Cox%20Tee%20Dee%20049%20(2).html

http://sceptreflight.net/Model%20Engine%20Tests/Cox%20Tee%20Dee%20049.html

Lieven