Just finished building my fascination 46 with a magnum 61 mounted inverted and when I went to start it fuel freeflows.Can someone
tell me what's up/down???

Sounds like your tank is higher than the carb. Fuel is syphoning.

If you can't lower the tank, about your only option is to pinch the fuel line till you're ready to crank it.

Thanks Mike....It is as you say.Tank is mounted higher than carb.I thought there might be a problem when iI installed it.Only option I have is to move it to the belly pan.If I do that what are the odds of it catching on fire if I land too hard?

slim to none. I would really say , none. You apparently have not seen a good crash where the plane
loks like it came out of a food processor.

power - start your plane upside down! Also if you really wanna start it normally then do not prime the engine. If you can please use a refueling valve, this will ensure that fuel does not feed into the carb while you are fueling up.

My experience indicates that if the centerline of the tank is not correct relative to the centerline of the carb there will be no end of operational problems (dead sticks, can’t set top end, won’t idle, lean at end of a run, etc.

I thank you all for your insight!! I had to take a brace out so I could lower the tank and that solved the problem,but I had to mount the tank in reverse to clear the firewall. The magnum 61fs fired right up in this beautiful florida weather...About 82 degrees although I'm pretty sure I half fried the glow plug because I have to leave the igniter on longer than usual and I do notice a drop in rpm when I do remove it. Don't have a spare at the moment so I guess its miller time!!!!.....Again thanks to all for your help!!!

Slowing down when you remove the nistarter is a sign of the low mixture being to rich which happens when you invert the engine. you might try leaning it out a bit.