If you are indeed gettings "hits" then changing the receiver isn't going to do anything as the new receiver will get hit as well since it's on the same channel.

I also doubt that the engine needs replaced as well. More likely it just needs to be tuned properly, or there is another issue causing your problems. If the engine is dying on you in flight as you stated I would take a look at the fuel system to ensure that you don't have any issues with it.

Ken