In my 09 GE8 my lower O-rings keep getting torn on my injectors, I have installed with and without lube, the engine sucks air into the cylinders past the o-rings. I changed the rings like 50 miles ago and they are already allowing air to pass again. I talked with some DSM guys and they were saying that in the older DSMs if the fuel rail nuts were over tightened it would cause the o-rings to tear. Does anyone have any experience with the rings that can help me out?

 

I don't know much of anything about this other than O-rings are manufactured with different materials. Buna-N or Viton should be acceptable in fueling applications, with Viton having the higher heat range. The only other thing I can think of is size. Are yours sized correctly for the application? If they're just one size off, they will fail to compress properly and will leak by. The injector manufacturer ought to be able to tell you the correct size -- o-ring sizes are standardized and globally recognized.