Popping sound from Savage X?????
 

So I picked up a Savage X that pretty much looked brand new for $100 off of craigslist the other. No RX/TX came with it which is fine because I have my own (DX3c and SR300s),but did hook up an extra that he had to try to get the truck running (I knew it wasn't before I went over). We put the roto start to it and it sounded like it wanted to but wouldn't. Sounded like it also had compression as well. The lines were bone dry and at the time I didn't know the trick about covering the end off the pipe. So I did that this morning and got the fuel going but it still wont start. When you run the roto start it makes a popping sound. Sounds like its coming from or echoing from the pipe. And of course never kicks over. I figure if I have to change the motor I still got an ok deal, but I would prefer the 4.6 in it work.
Any ideas as to whats going on? This nitro thing is still pretty new to me.

Have YOU checked your glow plug? Is the roto start turning the engine fast enuf?

check your glow plug, check glow ignitor is charged, make sure roto start battery is fully charged turn the needles to stock and then lean then 1/8 each(not middle speed needle) you will still be rich though.
if not then check compression. take it out and turn it over via flywheel and see how much resistance at top dead centre.

Glow plugs are good. Put in two different new ones and the one from my MGT. Put it to factory settings and tried to tune it. I got it running for about 4-5 minutes, but to get it running i had to set it rich as hell and its spraying all over the place. To the point you can see every spot on my drive way and street were I gave it gas. Then after that, it stalled and wont start again. Took the head off, flipped and turned it. It's not flooded. And roto start has a good battery.
What am I going to be looking for ex on the compression check? I does get harder to turn and then eases up. And when I had the head off and slowly turned it you could hear and see the pop. Almost like pulling a suction cup off the shower wall.