I have a magnum 52 xls 2 stroke engine. it runs fine but will not stop. it will not stop even when I put my finger over the carb? where could this thing be leaking air. the carb gasket looks good

I have the same engine and the same problem.
I would close the carb, but it would die only after like 7 seconds.
I checked for airlieks, but everything seemed to be fine.
Closing muffler kills it.

Now its been about a gallon trough my engine and it stalls when I close it.
Maybe its because it was new. Other than that I love it. Very powerful!

You have an air leak somewhere.

Make sure the bolts in the backplate are tight and make sure the carb is well seated against the o-ring. I usually press my thumb down hard on the carb while tightning the screw.

If that doesn't work, try the following to pin down where the air leak is. Do these ONE AT A TIME.

Take some vasoline and put it on pretty heavy all around the seam between the backplate and the crankcase of the engine. Start the engine, let it run about 30 - 40 seconds and see if it will shut down.

If it doesn't shut down repeat with the carb. Make sure the seam/gap between the carb and throat is completely covered - you may want to use a toothpick to get the areas that are hard to get to.

You only want to run the engine about 30 - 40 seconds before shutting it down because the heat generated by the engine can liquify the vasoline after much more time and make clean up more difficult.

If the vasoline does the trick, disassemble the part and clean the affected area with some alcohol. Then use some silicone sealer and put a bead of that on the mating surfaces, reassemble and let dry.

If it still won't shut down after using vasoline to seal any air leaks, the front bearing/seal is leaking OR there is an internal problem with the carb (barrel not fitting properly, barrel seals). You will need to call and return the engine.

Hope this helps.

If you need to return the engine or carb, I know that Magnum/Global gas GREAT customer service.

I got a bad carburetor (could not be converted to Remote Needle because they accidentally glued down the needle[sm=bananahead.gif] or overtightened it) on my Magnum XLS46, which has the same carb as yours.

Their website (and Tower) lists the carb as about $50. The customer service people replaced the carb for FREE. I didn't have to pay shipping and I didn't have to mail them the broken carb. The people are great!

This is a problem with many China-made engines... the carbs are just not that good. My friend finally gave in and tossed in the towel, literally. He would take his rag and chuck it into the turning prop. That worked pretty well :-) Honestly, the carbs are the first to go. I would try all the advice here and, if all else fails, throw in the towel!

My Magnum 40 did the exact same thing and for me....the needle seat came out. Inside the carb where the barrel the seat slipped out and was leaking air. I reseated it and now it's fine.....just a suggestion!!

I don't know if the larger Mags (.40 and bigger) do this, but the smaller Mags I use in combat (.28/.25/.15) all have problems with air leaking around the o-rings on the high and low speed needle valves. It doesn't show up with the symptoms you metion (not shutting down), but as erratic running. Some fuel tubing fixes it right up. You can also replace the o-rings with larger, better quality o-rings, or do a couple of other things to improve the seal.

In general, if the engine runs fun, but won't shut down, the leak is pretty small, and probibly not in the needle areas like I mention, instead, I think Campy has it right. If it was me, though, I'd just tear down the engine and seal everything back up with RTV. After all, putting a bit of sealant on something that didn't need it won't hurt anything .

Try the head. My bolts started to get loose where the head bolts on top of the cylinder. I think there's 6 allen screws on top. I also love mine as long as it has plenty of air to cool it off and is not inside a cowl. Lots of power!