MEP 003A Governor not following load

[Ak40]

First time post
I’m considering purchasing one of 8 MEP 003A but after load testing 2 units both failed to hold RPM as progressively higher loads were applied. I did see the droop settings adjustment in TM my question to you operators, is the governor a part know for failure and or to be problematic or am I most likely looking at adjustments or possibly a sticky fuel injection pump?
I must say this looks like fine group of people here

 

[jamawieb]

More than likely the injectors need to be calibrated or cleaned. Storeman who is a member use to do all mine. Try to adjust the governor but more than likely it won't help because your not getting the correct fuel.
I've worked on 100's of these and anytime they wouldn't hold load was because of the injectors.

 

[Ak40]

Thanks for the tip about the injectors sorry but I failed to post that the set has no problem holding load if you adjust throttle while at 85% load. Also when shedding load both units would speed up as load drops.

 

[jamawieb]

Yeah sounds like injectors are the problem because your having to manually increasing the fuel.

 

[Ray70]

Also, check the linkage going to the IP for free movement. I once had an 003A with 5 hours documented on the clock that was doing the same thing, only it would start to droop at about 40-50% load. Ended up being that the expanding section of linkage ( not sure of technical term... ) was bound up because someone had painted it and the thick CARC paint was binding up the linkage. I scraped the paint off with a razor blade and it would then easily take 125% load.

 

[Guyfang]

Everyone here seems to like this Seafoam stuff. I always used a few bottles of injector/IP cleaner. But in any case, try running some Seafoam and a tank of fuel through the sets. I would run a half tank through, then let it sit a day or three. Then run the rest through. If the problem isn't better, then follow jamawieb's advice in post #2. Also be sure to check Ray's post #5. The linkage can cause this problem. When you pull off to check and clean, pull the ends apart. Let go and it should snap back into place.

 

[Ak40]

Thanks, Ray and Guyfang
I’ve been around a lot of governed engines and this sure sounds like a governor issue. I’ve done a lot of research on these units and from what I gathered they are very tough and reliable gen sets these units that I’m looking at all appear to just been through the tier 2 depot upgrade most have less than 10 hours on the Hobbs meter. I’m going back and pick hopefully a good unit. Take few wrenches and made one work seller has a 4 element range top for load testing 9.2 kw of load. Any and all advice will be welcome.

 

[Chainbreaker]

Just a FYI...these units Hz meter's frequency transducer is very prone to providing erroneous readings or outright fail as they age. First, use a known good Hertz meter (Kill-A-Watt works great via the convenience outlet) to set at TM's specified 61.5 Hz after warmup at NO load. This is the setting you should leave it at and shut it down at ("if" everything is working properly no need to touch it again). When adjusted to 61.5 Hz it will run the engine slightly above 1800 RPM to allow for droop under load. When placed under normal load you normally will see a slight Hz dip to around 58-59 Hz until it settles in at target 60 Hz. BTW, the actual governor mechanism uses centrifugal weights (steel balls) and I've never heard of anyone mentioning that part failing. Usually, as stated above by others, it's a linkage adjustment issue or engine fueling related (injectors, injection pump).

 

[Guyfang]

The chances that the governor is bad, is slim or none. And that two gen sets in same hemisphere being bad, are even worse. Truly, probably the only thing on a 002, or 003 that I have not had to fool with or change, is the govenor.

 

[Keith_J]

The governor is nearly bulletproof. But they can be adjusted and when out of spec, they will droop or reduce frequency when loaded. This is adjusted via the notched wheel which positions the spring on the governor arm.
I adjust these to where there is a tiny bit of hunting after shedding a good load (50%). Hunting is speed oscillation, my goal is no more than 5 seconds after load shedding.

Its purely mechanical so you either have droop or hunting.