Print head problem

Ever since I bought the Robo3d I've have print head problems. To begin with the first print head jammed and I found no way to unjam it so I bought the e3d print head and the printer lost all control. The printer won't go above 190 degrees and the print head I believe is not sealed since I cannot get it to 300 degrees. Therefore the e3d jams up and doesn't allow the filament to properly extrude. The thermistor seems to have a problem. Is it possible that I could find the print head and its corresponding wires to buy them and successfully reconstruct the print head?

 

I have upgraded from my broken 2013 stock Hotend to the E3D V6 hotend with the PTFE Tube.
You have to change in the configuration.h file the max temp setting, further I do not understand why you need to go 300 degree...? This temp will destroy the E3D termistor when I remember right. Temps up to 285 should be OK for all possible Filaments.
My E3D performs perfectly...

Br,

Matthias

 

I understand but the 300 degrees is to allow the hot end to seal its components therefore I believe that the hotend has a problem. Or the thermistor itself. Do you guys know where I can buy the print head? The original cables and all? (Thermistor and heat cable?)