I have inherited a JD Z355R zero turn mower from my dad and it runs great, until lately. The issue I have is that after about 10 minutes of mowing, it starts losing power and tries to stall out. I have changed the fuel filter, fuel pump, air filter and have sprayed Gum-Out carb cleaner into the intake and this doesn't seem to help. Has anyone encountered this problem? Hopefully its a simple fix that I might be able to do myself instead of taking it to the dealer or repair shop and having to pay too much for the shop labour.