Dope color matching

OK this is the engine that I stuck a electric starter to. Cox BW .049. What I found was that the gears on the crank shaft where worn really bad. (Thanks for telling me how to get it apart.)
I had a old engine that I have been robbing parts for. I used the case and crank shaft from that engine. I put it together last night and took my time to make sure it all fit. I ran it this morning and it started right up. I let it run and then pointed the plane up and down like it was doing climbs and dives. The engine quit. I started it right back up. Same thing.
1. Should it keep running when I point it up or down? Or when your flying the plane the fuel moves different?
2. Should I try and move the pick up?

As always I thank you for any help.

Thanks
Paul

(snip)
>1. Should it keep running when I point it up or down? Or
>when your flying the plane the fuel moves different?
>2. Should I try and move the pick up?

>
>Thanks
>Paul

Should it keep running when pointed up? Yes, if the pickup tube is stuck in the back of the tank properly. Should it then keep running when pointed down? No. When you point it down, the tube will become uncovered and the engine will quit as if it had no fuel in the tank. This is an easy way to shut off a "regular" plane after you start it up and decide you need to shut it down again. (Pick up the plane and point the nose down.) Note: In flight the fuel will be "shoved" to the back and outside of the tank and then the engine will remain running even when the plane is pointing down.

As to moving the pick up, if it goes to the back and outside of the tank, then it is fine. If not, then move it so that it does.

LAST EDITED ON Mar-10-04 AT 01:16 PM (CDT)
 
Paul,

Wow, I've never heard of stripping the knurl on a drive washer. "Knurl" is the correct name for what I think you are calling gears. In this case it is a straight knurl.

Leonard has hit a couple points but I can think of a couple more to check. As you mentioned, check the pickup location, but also check the length, it should loop around and reack to the bottom of the tank at the rear. Check far a crack or hole in the pickup tube. Also check that the tube fits well in the nipple and is not sucking air. Another thing, is the o-ring or gasket in place btween the cover and the tank venturi tube?

When I am getting serious, I use a small fuel hose coupler between the backplate and a bent metal tube that goes exactly where I want it. This way you can really control the position of the pickup and be sure it will stay where you put it! Far better than hoping a flexed piece of fuel hose will remain where it was when you last saw it.

I can't help it, but that sounds like a complaint to the doctor, "it hurts when I do this". DR, "so don't do that". So don't point it up or down.

Paul,

Ty's tongue-in-cheek reply -- "so, don't do that." is not that far off from a good simple, serious reply...

Yes, (forgive me Leonard) the fuel does act differently in flight compared to the static (read" non-moving") conditions on the ground. The angles of forces on the fuel are much different from the 'static head' change we get from pointing the nose up or down.

It just might fly well if you 'peak' the RPM with the wings level, then back off ("richen" it a bit) just enough to hear a change. If not, the tank volume is small-ish, and you'll have another chance to 'tune' it in a few moments.

Glad you put together pieces that will, at least, run for you. Good on ya!

rootbeard,
As Leonard mentioned pointing the plane down uncovers the fuel line and you shortly start sucking air. The same thing can happen when you point the nose up if you happen to tilt the inboard wing down while holding the nose up and the fuel level is below the pickup line.
I think the folks who suggested flying it to check it out have the right idea.

Good luck,
George