ORIGINAL: BoneHead
Hey Jeremy,
It sounds like the fuel is not being drawn into the carb on the times it doesn't stay running. You want to take a look at where the fuel tank is placed. Is it below the engine or far away? I know there is a way to prime the engine without putting a few drops of fuel down the carb. I'm sure someone will post exactly how to do it. I think it's done by placing your finger over the carb and turning until the fuel comes up to it, then turn it a couple of more times, and it should be primed. Don't quote me on this....but I belive it's how it's done!!
Once one of the "Seasoned" veterans post.......I'm sure you will not have any more problems starting the OS .25 LA.
This does sound like what is happening. If you use the technique above, MAKE SURE to do this with the glow plug igniter OFF the engine. You don't want to risk having fingers in the way should it fire off when you turn over the prop.
If I need to prime mine, I cover the carb opening with the tip of a finger, and TURN the prop over, NOT flip it over.
The ways Hal stated also work well. The benefit of putting your finger over the muffler outlet is that you can spin the engine over withan electric starter, glow igniter connected and when it fires up, you are good to go. With this technique, there is little chance of flooding the engine, unlike the other two ways.