HELP. MEP803 Generator surges up and down.

[FullBlast]

I have MEP803A generator that starts right up, runs great for about 3-5 minutes and then it starts slowly surging up and down.

It surges so slowly that it is hard to even hear that it is surging but the HZ meter goes from about a 56 and swings up to 62HZ.

I put new fuel, and fuel filters in it and it still does it.

Any ideas on what else to check?

 

[Light in the Dark]

Exactly which filters did you put in new? Just want to clarify. Has this generator run fine before now, or is this a new gen (and problem) to you? Fuel pumps can heat up and slow (slow failure), but I want to verify filters first.

 

[FullBlast]

I am sorry, I thought I replied to this.

I replaced the metal fuel filter, the hard to get one and also the small drop in element on that hangs on the side of the engine.

 

[Guyfang]

I have MEP803A generator that starts right up, runs great for about 3-5 minutes and then it starts slowly surging up and down.

It surges so slowly that it is hard to even hear that it is surging but the HZ meter goes from about a 56 and swings up to 62HZ.

I put new fuel, and fuel filters in it and it still does it.

Any ideas on what else to check?

under load? Or no load?

 

[Light in the Dark]

Do you have a small inline filter just south of your fuel pump, on the radiator wall? How old is this machine? How do the fuel lines look? They could be swelling and restricting flow. How about the fuel tank, have you ever cleaned it out? You may have debris floating around, causing sufficient fuel flow intermittently.

 

[jamawieb]

I had a unit one time that would surge with no load and it turned out to be the linkage on the fuel cutoff solenoid. It was binding and not letting the fuel cutoff lever move all the way toward the solenoid, which is fully open. I could move the fuel lever back after it was started and it would stop the surging. I adjusted the linkage from binding and it fixed the problem.

 

[Light in the Dark]

Good tip, thanks Jimmy

 

[FullBlast]

under load? Or no load?

No load.

 

[FullBlast]

Do you have a small inline filter just south of your fuel pump, on the radiator wall? How old is this machine? How do the fuel lines look? They could be swelling and restricting flow. How about the fuel tank, have you ever cleaned it out? You may have debris floating around, causing sufficient fuel flow intermittently.

I am not sure if there is a filter there or not. I know what you are talking about for sure. I will check that out along with the other items you mentioned.

I think it is a 90's model.

 

[FullBlast]

I had a unit one time that would surge with no load and it turned out to be the linkage on the fuel cutoff solenoid. It was binding and not letting the fuel cutoff lever move all the way toward the solenoid, which is fully open. I could move the fuel lever back after it was started and it would stop the surging. I adjusted the linkage from binding and it fixed the problem.

It is interesting that you mention that. When I go to start the machine I have to help manually pull back on the shutoff to get it to the run position, it is very possible it is binding up, however when I did that I thought sure I had pulled it all the way.

i will check these things out.

Thanks for these suggestions guys!!

 

[Guyfang]

Or you could have a L5 that dosnt work right. You need to test if it's getting 24 volts to the pull circuit. Take a look at the last few pages of thread " 803 Bogs down", or something like that

 

[155mm]

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