Hi,
Is there anyone out there who is experienced with the Cox Pee Wee. I am having a time trying to start it. I haven't attached it to my plane yet, put rather to a two by four. I am following the instruction on how to get it to start, but it keeps leaking gas from the back and the most I can get it to run for is about 2 seconds.
Any Suggestions?
Thanks Eddie
Sounds as if it's running on the fuel that you shoot into the exhaust port and then dying because it's not drawing fuel through the venturi. You can disassemble the tank and make sure that the pickup tube is attached to the needle valve nipple and that the tube is pointing down to the bottom of the tank. Some engines that have been sitting around for years have hard, cracked pickup tubes. Also make sure that the tank has a good seal. If it's leaking fuel from the back that could mean that all the fuel is gone by the time you get it to start, and then it just quits.
The general procedure for starting a cox reed valve engine is to prime and start, prime and start, prime and start, until the fuel gets sucked up the pickup tube and into the venturi and it will continue to run for more than a second or two. Once you learn this procedure you may find yourself priming and starting for half an hour without even thinking about it if there is a problem. If everything is in order it should take only 2 to 5 times on a Pee Wee. I can usually get my Black Widow and Texaco to run after only 2 starts at the beginning of the day.
One thing that I like to do when I'm having trouble is to pressurize the tank to prime the pickup tube and venturi. After you fill the tank and the fuel starts to come out the breather hole, cover the breather hole and shoot a bit more fuel into the tank. The fuel will be forced up the pickup tube and into the venturi. If you remove the needle valve and do this, you can see the fuel ooze out of the needle valve hole. Then when the engine first fires up, it will be more likely to run because it's already drawing fuel.
If you do all of this and still can't get it to continue running, then you likely have a blockage in the fuel line or venturi. You may also want to check the reed valve to make sure that it isn't stuck in the open position or in the closed position. Either way will make it not run. If you suspect right now that your problem may be a result of your engine sitting around and getting gummy and dirty for a few years, maybe you should start by disassembling everything, washing it in a small container of fresh fuel (use the cheap stuff or denatured alcohol from the hardware store) and putting it together nice and clean.
Let us know what happens.
Well Look at that...
I took the 020 off the 2x4 last night in defeat. I assumed that the gas was leaking out from the back through the little screen vent back there, but no. I filled the tank unattached to find the leak and it is coming from the lower right screws back there.
I have never taken an engine apart before and I am a little apprehensive to dive in unassisted. Honestly there were a lot of parts that you mentioned in your post that I didn't know. Like, venturi, pickup tube i don't know what they are. But the tank is leaking, so I have to get that stopped.
Thanks, Eddie
Maybe you could just snug the screws and it would stop leaking. If the screw is loose, then the joint between the crankcase and tank is probably loose as well. If that's not sealed then it can't draw fuel. Try tightening everything and see if it will run. Just make sure you don't overtighten it. It's pretty easy to break those little screws.
There should be a gasket between the tank and the engine. I'll bet that it is missing.
Jim - AMA 501383 (remove NOSPAM to reply)
I GOT IT STARTED!!
The problem is in the back screw still though. All the fuel was leaking out of it right there. I filled the hole with some metal cement. It worked to stop the leak for a minute, but it looks like the cement melts away after three of four tanks. I will have to come up with a gasket of some kind.
Kind of disappointed in COX or Estes, whoever they are. The engine is brand new out of the box and broken. I could send it back for a replacement but that is a pain. Oh well. I will find a gasket or make one.
Thanks for your help. Eddie
If you mean it is leaking through where one of the four tank retaining bolts recesses into the backplate.. it may just be a seal problem, however it is very easy to crack the backplate in that area by overtightening of the screws. Been there, got the t-shirt etc. Watch your torque - snug for a 2-56 bolt (I think they're 2-56, I'm not clutching a Pee Wee at the moment) ain't the same as for a 6-32! Just a cautionary note, that's all. You would not be the first person with this problem.
Mike D.
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