This is more of a general diesel question. While operating at normal throttle setting the engine will suddenly speed up, as if throttle were increased. After a few seconds, or minutes, the engine returns to original speed. During the speed-up, throttling back will sometimes reduce RPMs, sometimes not. This first happened years ago, but is getting more frequent. Yesterday the engine quit completely, but later restarted ok. I suspect the governor (which I assume is in the injector pump). Clean fuel, new filter about 20 hours ago, throttle and connections all seem ok. I doubt if it could be the usual suspects (fuel lift pump, clogged lines, clogged injectors, air in the system, etc.) because most of the time it runs fine. I'm about ready to pull the injector pump for rebuild. Any ideas?
The usual suspects are guilty until proven innocent sometimes. If you can rig up a fuel pressure gauge from right next to the injection pump that will tell you conclusively whether or not the pump is getting pressure when it acts up. A length of clear hose in the return line will tell you if there's air in the fuel also. If it acts up a couple times with good pressure and no air, then it seems like pump time to me.
Thanks. Hard to test that way because trouble is intermittent and short lived. Also, can intermittent racing of the engine be due to low fuel pressure?
Yes, that's what an engine does when running out of fuel, races a little, settles down, races a bit more, then dies. Run the pressure line to a gauge in the cab, and a section of the return also. Then run it and watch when it happens.
Didn't realize that; good idea. Will check...............thanks. Also. I just remembered that I put in new canister filter/separator) but did not yet install new in-line filter, so will replace that first.
Does this engine have a glow plug fitted to the inlet manifold? These will have a fuel line attached & they will often leak fuel into the intake. If so, remove the fuel line cut off the ends & weld up the steel tubes at the hose ends & refit the ends as plugs. If you need the heater to start the engine in the winter, you will need to replace the heater element.
No; no glow plug.