Thanks again for checking back. No, I can't reinstall everything back because I can't get the union nut into the filter base because it's stripped.
As far as bypassing the filter, there a lot of hoses/pipes on this filter. On the left side is the inlet from the Racor. On the right side is an outlet hose to somewhere (fuel pump?) and an inlet back from somewhere. On the top of the filter is what looks like a return from the injectors attached by a banjo fitting to the fuel return line back to the tank. How would I bypass this? I've been looking at the diagrams and reading about diesels but haven't found anything good about it.
Sounds like they use the filter as a "distribution" point, kind of complex. I assume this is the secondary engine mounted filter behind the Racor? A long time ago I melted down a couple of two strokes running them too lean trying to get maximum power out of them which I did, for a short time. I am not sure you can run a diesel "lean" as they have no throttle plate to regulate the amount of airflow. I think if they are not getting enough fuel they just slow down or stop. I also assume the injector pump is all mechanical with no electronic "magic" controllers? I am not an expert on anything but have worked on a number both gas and diesel engines over the years. It would appear that your recent filter change may be causing the high rev problem but I can't figure out how or why. The injector pump is the last point of fuel distribution into the engine and that would be suspect to me. Maybe when changing the secondary filter some debris was dis-lodged and found it's way into the injector pump causing the high rev problem?