MEP-802A won't run

[steiner]

I recently purchased this generator at auction. It only has a little over 6 hours on the meter. When I bought it all fluids had been drained.

I put oil, water and diesel in it. I opened the bottom drain on the filter and ran the electric fuel pump until fuel flowed nicely. I then slightly open the screws at the top to bleed any remaining air. I then tried to start it with no luck. The engine turns over just fine but will not fire. I then cracked the line at each of the high pressure pumps and fuel did come out but I was expecting it to spray as opposed to just dribble out. Thinking this was my problem I removed one of the high pressure pumps as per the manual. Disassembled the pump, didn't find anything obvious so I just put it back together and installed it back into the engine. Before I hooked the fuel supply line back up, I verified I was getting good fuel flow to the pump via the electric pump. I then connected the fuel line back to the high pressure pump without the rigid fuel line that goes to the injector. When I turn the engine over, fuel does come out of the top of the high pressure pump but it only shoots upward about 1 inch at the most. Is this normal or should it be shooting much higher? Thanks for any advice.

 

[kloppk]

When you put S1 in START does the Fuel Shutoff Solenoid fully retract?

Like this....




This is the extended fuel solenoid when set is stopped

 

[steiner]

When you put S1 in START does the Fuel Shutoff Solenoid fully retract?

Like this....
View attachment 849414



This is the extended fuel solenoid when set is stopped
View attachment 849415

Thanks for the help...
Yes, it does fully retract. Another interesting thing to add. I removed both the intake filter and muffler so that I could get access to the injectors as I wanted to verify fuel was getting there. It turns out that it is. So the interesting part is that when I turn the engine over now (muffler still not attached) I can see puffs of fog come out the exhaust ports. I assume this is the atomized diesel that never ignited. This makes me believe that fuel is getting to each cylinder.

 

[LBCDguy]

I had a similar issue, i had everything, fuel up to the injectors, plenty of cranking power, the solenoid was moving etc.. so i wanted to see what the valves were doing, how they were moving. As it turns out when i would crank the engine over none of the valve train would move?!?! Right then i said to myself we must have a mechanic engine failure. I pulled one of the pumps out to watch the cam move and i cranked it again and the cam was stationary. I pulled the front cover off and as it turns out the keyway off the cam gear had broken off.

 

[steiner]

Thanks...u was thinking along a different line that maybe I didn't have adequate compression due to a valve not completely closing. So I took off one of the rocker covers and turned the engine over
I can see both rocker arms moving. I then waited 30 minutes for the hydraulic pressure to bleed off from the lifters and the I was able to rotate the push rods with my fingers. I assumed that proves the valves are closing completely. Thanks for the idea though.

 

[LBCDguy]

is the fuel return circuit blocked somehow? are injection nozzles hanging up or stuck open? did you do a compression test?

 

[steiner]

LBCDguy,

I don't know to all of your questions. I will check the fuel return circuit tomorrow. I was thinking about doing a compression test but wasn't sure how since there isn't a spark plug hole to thread my tester into. Also, I couldn't find what the compression should be other than it has an 18.5:1 compression ratio.

How do you check for a hung up or stuck open injection nozzle?

Thanks for the ideas...

 

[steiner]

I also wanted to mention something else I found. In the -24 manual, Figure 9 shows the governor system. Does anyone know are some of these parts internal to the engine. I can see the parts #29 thru #35 which appear to be associated with changing the frequency. I can also see parts #44 thru #47 and #7 screws which are associated with the governor solenoid. I can't see any of the other parts that are shown in Figure 9. I just want to make sure someone didn't remove these parts before I purchased the unit.

 

[Light in the Dark]

Have you followed the TM steps about "ENGINE CRANKS BUT FAILS TO START."?

 

[steiner]

I have attempted to. The very first step is to check for the stop/start lever in the wrong position. It tells you to adjust the lever as per paragraph 3-23.5. This paragraph then refers you to figure 3-19. This is the figure I previously wrote about that I don't see some of the parts shown in this figure and wondered if they were internal to the engine but this wouldn't make sense as they would be difficult to adjust. However, I can't see any attachment points where it looks like something is missing. For example, I don't see part #6 anywhere. If someone has one of these generators and could take a picture of theirs that would be very helpful.

I have certainly done steps 2 and 3. I don't have a fuel injector tester so that makes step 4 difficult. As for step 5 fuel injection pump timing, with only 6 hours on the machine, I was the first person to break the paint off of the fuel injector pump lines. I know I have the exact same shims reinstalled that were originally there. I was just assuming the fuel injection pump timing was done correctly at the factory.

As for step 6 testing the fuel injection pump, I don't have a 3000 psi gauge. This is why I asked in one of my earlier posts regarding how high the fuel would typically spray vertically when the rigid line going to the injector is removed.

I guess I am trying to make certain that it isn't something simple that I have overlooked first.

 

[Light in the Dark]

Have you tested and inspected the MPU? It threads into the flywheel housing, below the starter

 

[steiner]

I will check it this evening. I just found the reference to it in the -24 manual.

 

[Guyfang]

I will check it this evening. I just found the reference to it in the -24 manual.

Do read and heed when fooling with the MPU. Test it in place first. Then pull it out to see if its whole or dirty. Then, read and heed again when re-installing it.

 

[steiner]

OK, so I tested the MPU as installed. I got right at 1 volt AC across terminals #3 and #6. I removed the sensor from the engine and cleaned the small amount of debris from the magnet. Reinstalled and adjusted so that I now get between 2.2 and 2.5 volts AC (book wants between 2 and 3 volts AC). Thought for sure that was going to be my problem but no luck. It still turns over fine but doesn't hit on either cylinder,.

 

[Guyfang]

If you THINK its low compression, open the -24 TM and find out how to make a water manometer. How to make a cheapie and how to use it are in the TM. Or use the simple test with paper over the oil inlet. If you can not find it, say something. I am not at home right now, so can not look it up.

 

[jamawieb]

When you open up the sealed injector system, it takes a while to get all the air out of the hard lines. Sometimes as many as 1-2 minutes of cranking, 4 or 5 times. If that doesnt work unhook the intake heaters and spray a very little amount of starting fluid in the intake (1 little squirt) to see if it fires. If it doesnt then your rings are stuck. It just takes alittle moisture on the rings to rust them in place. If thats the problem, try to pour mystery oil, diesel, wd40 sea foam, etc into the injector hole and let it sit. Hopefully they will free up. If they do you need to run it hard to really free up the rings.
Just had to replace the rings in an 803a with low hours because of this. This is why i dont like low hour units. Its either rings or froze injector pumps.

 

[steiner]

I really appreciate everyone's advice and knowledge. I just got called out of town so I won't be able to get back to work on it until next week. I will do what was suggested and let you know what I find. Thanks again.....

 

[steiner]

Well I tried a small squirt of starting fluid a few times and the engine never fired. I'm going to add some Marvel Mystery oil to each cylinder and let it soak for a week or so to see if has any effect. Thanks for everyone's ideas.

 

[Ray70]

What is happening when it's cranking? is it smoking at all? if so what color?
How does it sound while cranking, does it sound like its free spinning, or do you get the typical cyclical sound of valves opening and compression etc...
If it sounds like it is just free spinning you may have valves not sealing thus low compression.
Look at the joint between the exhaust manifold and muffler, is it black or oily looking? If so, that's a sign of wet stacking and adds to the possibility of carbon hanging up the valves.

 

[steiner]

Sorry for the long delay. Life kind of got in the way. I finally got around to disassembling the engine on this generator. I saw some corrosion in the exhaust manifold and suspected some water entered through the muffler. The problem was in fact the upper two rings on both pistons were stuck in their grooves. I honed the cylinders, replaced the rings and seated the valves while I was in there. Put it back together with a gasket set and it runs perfectly. Just in time for hurricane season. Thanks for everyone's advice. This little generator is really a nice unit.