Is there any way to limit top speed on a mechanical n14? Its in a 1991 Pete. My biggest concern with this truck is that its a crane and I dont want someone trying to run 100mph down the road with it. I would like to be able to keep it in the 60-65 range tops. I understand that in doing so I may have to limit rpms, etc. but thats about all I know though. Any help is appreciated.

yeah they used to be called "governers" (SP?) in the pre computer era. You should be able to govern that truck easy enough. I can't help you on how to do it though. I imagine a google search on "how to govern a mechanical N14" may turn up some good reading.

Yes you can change the rpms up or down and or change the fuel pressure. It's a pretty simple procedure. The back of the pump, on the bottom has a barrel held on by four 1/4" bolts, there is whats called a shim pack inside of this barrel, by adding or removing shims you will raise or lower the engines rpms. I am sorry I can't remember which lowers rpms, adding or removing shims. I would go to cummins and get a couple of extra gaskets and shims and experiment. Also inside is what is commonly referred to as the fuel button, it will have a number on it designating its size. It could be anywhere from a .00 to a 50 or I'm not even sure how high they go, but the lower the number the more fuel pressure you will have. Fuel pressure is power; rpms is speed. Don't mess with the fuel pressure. I am going off the top of my head with this information. If you want more detailed information let me know and tomorrow I will go out in the shop and take an old pump apart and come back with a few more details.

Thanks a ton for the info!! Im not sure if I will do it myself or have the pump shop do it, depends on how much free time I have. Now that I know it can be done, thats good info. Thanks!