Mep-802a Won't shut down

[Bigoz]

Has anyone else had a problem with there 802 shutting down? I have a Mep-802a I got when it had 200 hours on it, now a little over 1500 hours, and it has always ran and performed flawlessly. About 200 hours ago the fuel gauge started jumping around and stuck at the max fuel level and has stayed there. Still ran just fine. Then about 100 hours ago it didn't want to shut down. I normally run the gen-set for 24 hours+, hot refueling, and when ready to shut down I open the circuit to cool the generator then switch to the off position, engine slows down and dies. Now it slows down and after a minute or two starts to speed back up to normal speed. I've tried to manually close the fuel shut off solenoid but its already closed and won't close any more, I've turned the manual throttle all the down, pushed in the emergency stop button, turned of the master switch but it keeps on running, but will not produce any electrical power. After about 10 more minutes or running it will mysteriously shut off! The T.O.s I have don't have a trouble shooting guide and I don't want to just start replacing parts unnecessarily. Has anyone else experienced this? Any help or guidance will be greatly appreciated. Thanks. I love this site, I've already learned so much from other posts.

 

[Zed254]

These threads may help: https://www.steelsoldiers.com/showthread.php?170466-Too-much-of-a-good-thing-MEP-803a-wouldn-t-stop!

https://www.steelsoldiers.com/showthread.php?157445-Mep-803a-stopping-question

 

[Demoh]

If the injection pumps are adjusted too far to one side it will do this, basically the governor cant turn them off enough to stop the engine. Not saying that this is the problem in your case but it would be the first thing I would look at. If you touch the pumps you will need some way to calibrate them so they both contribute equally, which would be thermal imager or infrared temp gun. Ive run into this on sets Ive put new pumps on before calibrating them.

This condition it would act as if the gen set is starving for fuel though, like RPMs should go down. If its not then perhaps stuck parts of the fuel rail or governor.

 

[Bigoz]

Thanks, It's been running good for two years, it just started this a couple of months ago. When I first start it from cold and let it run for a few minutes it will shut off just fine, but after running at normal operating temperature for several hours is when it doesn't want to shut off. I read a post a year or so ago about "tuning up" your gen-set by running at 130% for a few hours to get rid of carbon build up etc. etc.. I have not done this yet and maybe it would help????

 

[Bmxenbrett]

Dont run it at 130percent. Theres no more "turning up" than what they did from the factory.

Follow the links posted above. Not turning off is a common issue.

 

[Bigoz]

O.K. I won't run at 130%. After thinking about it I think I saw running at 130% was on U-tube, not here. I didn't think 130% would do it any good! Thanks for the conformation!

 

[Guyfang]

When you run the generator, about how much load is being applied?

 

[Daybreak]

Howdy,

Cleaning the carbon, and wet stack issues is really running it at 100% for hours. The 130% is only for like 5 minutes. You do not want a prolong running over 100%. Any time a unit is run over 100%, it needs to be watched, listen to, and totally working good. IR thermometer readings, voltages, etc..

 

[Bigoz]

Normally the load is between 20-65%.

 

[Bigoz]

Do you think carbon or wet stack could cause it not to shut off properly? I've been thinking about hooking up an electric range top straight to the generator and trying to get it to 100% because I do have a lot of black carbon around the exhaust area.

 

[Guyfang]

No I dont think so. But go ahead and try it. The last several times I worked this problem it was:
1. Loose relay in the control panel.
2. Bad L5.
3. Bad wire connection on L5.
4. Linkage bent/loose at the L5 or at the fuel stop adjust.
5. Improper adjustment, L5 linkage to fuel stop.

 

[Bigoz]

Thanks, next time I go to the farm I'll double check those. I appreciate the information. Thanks....

 

[Ray70]

If you physically close the fuel shut off lever by hand and she keeps running you probably have an issue with either the governor, the fuel rack or a metering pump.
I had an LPW2 with the same issue recently. It turned out to be a problem with the lever arm that the fuel solenoid attaches to. Inside the motor on the other end of that shaft there is a D-flat notch and a nut that holds the inner arm on the shaft. Whoever assembled the arm assembly didn't align the D-flat on the end of the shaft with the D-shaped hole in the arm. This caused the arm to only be held on by the friction of the nut itself, eventually allowing the arm to move and rotate slightly on the shaft, making it so that moving the lever to the off position was not pulling the rack back far enough to turn the metering pumps completely off.
Unfortunately if this happens to be your issue, it means pulling the fan, crank pulley and timing cover just to gain access. With the engine in the machine it will probably be a bit awkward to see inside to work unless you remove the whole radiator end of the machine.
Hopefully you have a simple problem to solve! Good luck.