just gettin back in to rc again and still remember much of the basics and kinda remember how to take it all apart and back together again. took apart the engine ,by the way this is a 2.5 jato, and i see were the glo plug is firing on the piston head. im sure this is some what normal but i was actually considering replacing the piston. everything seems fine with the engine,no cracks or scratches on the cylinder walls,she still pulls quit smoothly with good compression. im wondering if its a good idea to actually change the piston and sleeve? there is residue from the glo plug firing on the top of the piston.
any and all suggestions are greatly appreciated.
There's no need to replace anything until it looses compression or something breaks. Dark residue on the piston means it's been running a little rich, not necessarily a bad thing. Just don't let it get to rich or it can break a rod.
ok cool man thanks for the reply!