Shen Heng died after holding on for a year following his arrival at Gu Shanhai's Five Elements Sect. Actually, his soul was in an extremely dire state, and if it weren't for Gu Shanhai's help in adjusting it, he wouldn't have lasted a year—three months at most before he would die. The nine months that followed were due to his willpower and Gu Shanhai's assistance. Had his will to live been any weaker, he wouldn't have lasted so long.
In the meantime, Gu Shanhai obtained a vast amount of mecha-related knowledge from Shen Heng, completely emptying the knowledge of the other as a level-one researcher.
To build a mecha, one needs to cover many disciplines such as materials science, computer science, and energy studies. Shen Heng actually didn't teach Gu Shanhai, for there simply wasn't enough time; he just wrote down all the respective knowledge points, leaving Gu Shanhai to study them on his own.
