well since no one has made a statement on this,I will just throw this in, I have two 2005-2006 chinese tractors both with about 1000 hrs on each and have had no issues with the injectors that came with those two engines so far (20 hp yangdong,and a 50 hp Quanchi). but these are also non electric injectors, old school type I assume a bosch rip off as the pumps are.