- 117
- 119
- 43
- Location
- Los Angeles/CA
My MEP531 starts up easily and runs, but it immediately starts to overspeed. The engine blows tons of smoke and pegs out the frequency gauge, and is obviously revving way too high.
Clicking the "Stop" lever while holding the governor lever by hand, I can control the engine speed and get the frequency gauge down to 60-65hz. At that speed the engine sounds much better and the exhaust clears right up.
I spent a couple hours today reading the TM and looking at my generator, but I have no idea how to fix it. I am new to small diesels, but based on the symptoms above I am thinking the governor fly weights are stuck or not working, and causing the engine to try to rev up as high as possible. Is there a way to diagnose this without disassembling the engine?
It looks like the fuel pump lever is centered in the governor fork like it should be:
![Pump Lever.jpg Pump Lever.jpg](https://www.steelsoldiers.com/data/attachments/516/516231-1219e48efbc4de234342d712bfb35288.jpg)
I have tried every possible combination of spring positions, but the generator always overspeeds no matter how the springs are set. Also the image in the TM shows linkage arms with more holes than mine has so its not super clear how to put this part together, but as mentioned I tried every combination of holes.
![Governor Springs.jpg Governor Springs.jpg](https://www.steelsoldiers.com/data/attachments/516/516230-f06a9bc142dd59e12c576e38574b9c58.jpg)
![TM Settings.PNG TM Settings.PNG](https://www.steelsoldiers.com/data/attachments/516/516232-7fe59e44eb08e8279cc7677257e3f289.jpg)
Clicking the "Stop" lever while holding the governor lever by hand, I can control the engine speed and get the frequency gauge down to 60-65hz. At that speed the engine sounds much better and the exhaust clears right up.
I spent a couple hours today reading the TM and looking at my generator, but I have no idea how to fix it. I am new to small diesels, but based on the symptoms above I am thinking the governor fly weights are stuck or not working, and causing the engine to try to rev up as high as possible. Is there a way to diagnose this without disassembling the engine?
It looks like the fuel pump lever is centered in the governor fork like it should be:
![Pump Lever.jpg Pump Lever.jpg](https://www.steelsoldiers.com/data/attachments/516/516231-1219e48efbc4de234342d712bfb35288.jpg)
I have tried every possible combination of spring positions, but the generator always overspeeds no matter how the springs are set. Also the image in the TM shows linkage arms with more holes than mine has so its not super clear how to put this part together, but as mentioned I tried every combination of holes.
![Governor Springs.jpg Governor Springs.jpg](https://www.steelsoldiers.com/data/attachments/516/516230-f06a9bc142dd59e12c576e38574b9c58.jpg)
![TM Settings.PNG TM Settings.PNG](https://www.steelsoldiers.com/data/attachments/516/516232-7fe59e44eb08e8279cc7677257e3f289.jpg)
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