This truck ran 10 minutes and went to storage according to seller, batteries still in place caused corrosion, they took a charge and I've got everything working excluding the engine because I haven't fixed the mesh and loose flywheel issues.
So, why the HPI engine? Was the RC10GT only available in kit version?

It's not dust, it's particles from the rotten balloons sealing the rx and rx pack. This is brand new, curiosity got the best of me and I checked some parts like the fuel tank, electronics and took the air filter out.