Cox .049 starting

Here's a trick you can try. Remove the needle completely, fill the tank, then put your finger on the overflow and pump in more fuel until it comes out the hole where the needle goes. Then reinstall the needle, back it out about 3 turns, prime the cylinder and start it up again.

The hard thing about starting a Cox engine is that you have to get the fuel all the way through the system, which is kind of a long path. It helps to take a shortcut by filling the induction system with fuel.

Once you get the fuel flowing, if it doesn't run smoothly you may have some crud in the works. At this point, cleaning it out may prove helpful. Don't forget that you may have to have a new gasket and O ring on hand if you disassemble the engine. The best thing to clean an engine with is fuel or alcohol.

What he said. Fuel is not getting through to cyl. Seems like mine was opened more than 3 turns out. mk

Thse things will run on a super rich mixrire and with the gloplug on a suitable voltage.

Sounds like the fuel feed is buggered.

Is this a reed valve one? They get gummed up badly.

Strip and soak everything in fuel. Check the needle valve area is well cleaned up..

Also note how it came out. Must go back the same way.

-- Ray

You can, with care, tease the phosphor bronze flat again..if you are stuck at a flying field 15 miles from home, and you came on yer bike :-)

Memories of 1967..

Thanks for all the good ideas! Fired up the sucker yesterday, by opening up the needle 6 turns. Then turned down to 5 1/4 turns for max RPM. Seemed to run a little rough in spots, but the 2nd run was better. It may still be a little dirty with old fuel, so I'll probably run a few tanks thru before it gets airborn this spring. I don't know where I got the idea of 3 turns to start?

I think I'll put a piece of tape on the wing with notes, so I will remember this spring.

Time to charge more batteries in the other planes, and start that next kit.

Regards to all.....

I know about this... :)

Dave

My guess is the fuel line and reed are gummed. It should all work free in time.

I doubt it will stay that way for long,..the first start on any of my lawnmower engines in the spring is always a dicky affair, followed by lots of blue smoke..after a couple of tankfuls, they get back to normal

Yup. Thats the spirit!

My Cox engines have always run at 2 to 4 turns, depending on what kind of engine and how fine the needle threads.

Barry ===== Home page

Paul, If you could get motors to run that people sent in, I'm IMPRESSED! Upon reflection, my .049 started at 6 turns because it was a little gunked up. As was mentioned above, I expect it will improve with use this spring. I think I just needed to think about what the engine was telling me when it would fire on the prime, but not continue. Lack of fuel. Duh!

Anyway, now I need to think about a new battery for the plane. It's an old Ni-cad, and may have had the weenie over time. I hear new batteries are cheaper than a new plane after loss of trons in the air!

Just started a new kit of a PT-40 I didn't know I had. But it needs some adjusting - taildragger, bolt on wings, less dihedral, maybe play with servo locations. Should do till the warm gets here.

Thanks for all the excellent help.

Regards.....

Seriously, get a new batt! Even fairly new batteries can fail esp if they are mounted using rubberbands wrapped around top and bottom. I lost a kit built Uproar which went straight in full throttle after one of the rubberbands managed to wear thru the insulation and shrink wrap and short the strap across one cell. Managed to save my Super Sportster 20 twice in one flight after the battery went south. Had just enough juice to get it back around and on the deck after two different dives towards the ground. Total miracle I got it back with no damage. When I got to the end of the field where it ended up, I had extremely sluggish rudder and elevator, practically no throttle and the ailerons wouldnt respond at all. That sucker should have gone home in a sack... By all means get a new batt!!!

So, Barry, I had to scroll down to the bottom of this thread to see that you contributed nothing to the thread but your name. I think I'll continue to top post in most cases. It seems to be the preferred method in business, by the way.

Think about it! If you have any kind of memory, you know what the threads history has been. Why scroll through all of the history again. Just add your comment to the top and be done with it. If you want to read it all again, "simply" scroll to the bottom and read up.

Harlan

But this is not buisness; it is usenet, and the proper way to comment is to eliminate other dialogue that you are not going to comment on, then reply with your answer. Just like I did here.

I probably have read 50 posts or more, and it might have been several hours or several days before I got back to this one. What is wrong with a quick review? Again, quick; trimming is an art some people are not considerate enough to do.

The key is in trimming away the unnecessary parts of the posts. Doing that, it takes very little time to skim through what was posted the last time.

Because it makes more sense to put your comment in after what you are replying to, otherwise you would need to reply with something like:

Scrolling through the history is necessary, because it makes more sense to put your comment in after what you were replying to, in the previous comment.

I'm sorry, Jim, but we just disagree. I do remember what I was responding to, so I usually have no need to review the history of a thread. I prefer to save time by answering on top. I got used to it in business and find it very comfortable. If it is against use net suggested protocol, so be it. It doesn't make it wrong. And if folks find it so objectionable that they decide not to respond to anything I write, that's ok, too; its only use net.

In short, the last thing said is usually at the top of my mind, and I prefer to maintain that order for the last thing written.

Have a great 2008, Jim! Many any crashes be easily repairable.

Harlan