MEP803A Wont Shut off

[tktsales]

I will try and keep this short but there is allot to explain.. I bought this set a month or so ago. It came in with the engine front cover off, the start/stop lever assy was missing, the number 1 injector pump missing. Without knowing any history I started by replacing this stuff with all new parts from Lister Petter. I did the quad fuse update, fluids, filter and new batteries and. well, it runs. It runs rather well in fact, Makes power according to the voltage meter, I did not put any load on it but it was blowing allot of carbon so that does need to be done however it wont shut down.. The stop solenoids turns off, the stop lever moves to the stop position, I cycled the stop lever back and forth a few times to run and back to stop. nothing. Eventually after a minute or so of course without the electric fuel pump running it does die out. So I have no experience with this specific engine. I have been in heavy truck and diesel repair all my life but never worked on these engines.. My guess is this is the reason the Govt had the front cover off and maybe they just gave up on fixing it.. When the cover was off I could move the fuel rack back and forth easily. The little fuel rack on the new injector pump was much tighter than I though would be normal but once the pump was install and had a little tension on the spring from the camshaft lobe, the main fuel rack that the Governor controls moved nice and free so I was not worried about it.

So this is the interesting part, There is one spring on that new start stop lever assy that is supposed to hook to a hole on the top of the camshaft thrust plate which is between the camshaft gear and the engine block.. This engine has no hole there. If you look at TM 9-2815-253-24P in figure 9 it is spring 41. This appears to just be a return spring for the start stop lever which is done by the solenoid so I had to guess that this engine does not need it and I simply left it out.. If you look at figure 14, number 10 is the camshaft and just to the left of the 10 you can see the thrust plate and that top right hole is where the springs is supposed to go. (the camshaft, gear and thrust plate are all one assy, not serviceable individually so I cant think someone has messed with this) I honestly don't know but again I could move that fuel control rack back and forth with the stop lever (when the front cover was off) so in my opinion if I move the lever to stop the fuel rack must be moving to the stop position right? Maybe not as it does not shut off, doesn't even slow down until it begins to starve for fuel.. The little screw that holds this stop lever assy inside the engine block was a bear to get in even without worrying about the little spring, There is just no room to get fingers in there around the cam gear and start the screw.

The engine is running the correct speed, I Have 60HZ and I was able to adjust the frequency so the governor does appear to be working correct BUT I don't want to continue to start this as if that fuel rack gets stuck it could possible overspeed the engine. I was thinking one of these injector pumps might be sticking but I would think that would limit the stop lever from returning.

Does any one have any experience with these governors and fuel control system? Is the spring I left out more than just a return for the lever itself? If so where does it connect to.. There is a clear picture in the Lister service manual so I am certain my engine does not have this, it is not broken it just looks like it was never there. I am still going to think this is not my issue and the problem is something else. Hoping someone might have had this issue before. Sorry for the long winded story.. Thanks for reading it through..

 

[tktsales]

Ok Well simple fix.. I guess this is a good example of how sometimes taking a little break from a problem and going back with a fresh view is a good thing..

There are 2 screws on the front cover that set the travel of the start/stop lever. These are typically adjusted and safety wired together to prevent tampering.. This safety wire had been cut by the Gov't when the engine front cover was removed. I simply had to back off the top screw to give the lever more travel in the stop direction and it shuts down perfect.. I know some of these engines used in other industrial applications (not generators) run at much higher RPM (2800-3000) and thus probably require much more travel on that lever so apparently there is a fine line between run and stop on these 1800 RPM engines.

Anyway I think I got a winner here, Everything seems to work I just need to round up a few misc items and put this unit into some load tests.. If anyone has a fan shroud and the flimsy perforated metal shields that go on each side of the radiator I think that is all I Need to make this unit complete..

 

[tktsales]

This was a duplicate reply. I could not delete it, only edit it.

 

[smokem joe]

I may have some of those shrouds. I'd have to look. I threw dozens of those in the scrap load last time. I take them off all the units I work on. I use a piece of one to cover the large hole in the bottom to keep rodents out and scrap the rest.

 

[mciikurzroot]

I'm with Smokin Joe, its the very first thing I take off, while I don't toss them in the trash, unless I sell one and a buyer specifically ask, its the last thing I ever think about. Those guards are for the most cautious of us and I'm not in that category, I still have a decent sense of danger and not to put my hands inside what these block, not intending to start a course on gen set fan safety, I just don't need or use emm, to each his own.. mac/mc

 

[mciikurzroot]

I like this idea using it to cover the openings in several locations, thanx Joe mac/mc

 

[tktsales]

Well I am only missing the left side of the fan shroud but in my mind the shroud assists in directing air flow across the radiator. In this enclosure its probably got nowhere else to go but I prefer to have an intact fan shroud.. As for the metal guards I am not overly concerned about them but if this unit does not fill my needs or the project I Have in mind does not pan out this will get sold and I prefer it to be complete with guards in place..

 

[Light in the Dark]

I've got guards for an 802, but not an 803. I take them off as soon as I can, make maintenance a real hassle. Good luck in finding what you need.

 

[Zed254]

I'm an ex-extrusion plant engineer and safety has been drilled into my head. I like having the guards in place on my 2 generators. They are the first 3 screws to remove the guard on a job that needs access behind them and the last 3 screws to go back on when job complete. They remain in place with oil and most filter changes.

 

[Guyfang]

I've got guards for an 802, but not an 803. I take them off as soon as I can, make maintenance a real hassle. Good luck in finding what you need.

The fan guards are supposed to be the same. Interchangeable.

 

[Light in the Dark]

The mounting holes are probably the same, but the size is of course difference how it protrudes into the depth of the engine bay.

 

[Guyfang]

I looked up the part numbers. They were the same. Maybe someone can measure them?

 

[Zed254]

I learned a loooong time ago not to argue with Obi-wan Guyfang. No measurements, but pics show same sized guards in both of my machines.

 

[Light in the Dark]

I could have sworn I've had them out of both sized machines and they were different. Hmm... I don't have an 803 in stock at the moment to compare.

 

[Guyfang]

At some point in time, the original part numbers and screens changed. There is two NSN's and part numbers for both sides. The early screens broke easily due to vibrating, and folks bending them back and forth to do things inside the set.

 

[Ray70]

LITD, I have been thinking about this for a couple days because I could swear the 802 and 803 were different as well. I looked at 2 of my machines last night and they are in fact different. The 803's I have are taller and have cut outs for the radiator cap and fuel pump, like Zed254's picture. My 802 ( at least the one I checked ) has a shorter rectangular screen that stays up above the fuel pump and below the radiator cap, no cut-outs. Theoretically they are interchangeable, but definitely have 2 versions out there. Maybe the difference is as Guy says, a revision change due to breaking, and not actually related to 802 vs. 803?? Either way you were not dreaming, there are 2 versions out there.

 

[Light in the Dark]

I feel slightly less crazy. Only slightly, though.

 

[Guyfang]

I have said twice. There is an old and new version.

 

[Light in the Dark]

 

[Zed254]

Hmmmm. Looks like my old 'assumed...' affliction is back. I just took a quick look at the OTHER side of my machines.....and I have different guards on that side. My 803 is a 2003 machine reset in 2012. The 802 is a 1998 machine reset in 2008.