02-18-2018, 05:23 PM
I also have a 903 and have heard the same thing. (That the 903's weakness are the valves and therefore you should avoid using the Jake.) I asked a local Cummins mechanic (The only local Cummins mechanic left who has worked on 903s in the past) if it was OK to use the Jake with my engine and he said it should be fine. Maybe he wants more work.