MEP-803a with Start/Stop Lever Issue

[Maestro]

I have been working on a MEP-803a I bought from auction that had a number of issues. Most of them were electrical, broken or missing parts. All those have been addressed and still can not get it started. The Metering Pumps were replaced and installed incorrect, I have fixed that. The front gear covered was removed at one time (covered in RTV), I am thinking as part of the metering pump replacement.

The problem I am having now even with the metering pumps installed correctly the start/stop level will not rotated clockwise (to the start position) once the fuel solenoid engages and pulls back. It will rotate if I move it myself, it not stuck. Looking at various online video the start/stop level appears to rotate clockwise on its own once the fuel solenoid moves back. Even when I remove the solenoid arm from the lever, it will not rotate on its own. I removed all the metering pumps to make sure the rack is not bent or hung up, it will move easily on it own and you can tell it has spring attached to it, it will move on its own from front to back of the engine with no effort. However the level is not rotating by itself even when the rack is moving.

Before I open the front of the gear housing cover and start looking inside I wanted to make sure I am not missing anything. The first picture the specific parts I am talking about. 45 is the lever which is connected to part 43. and it looks like spring 41 is also connect to it. I believe this spring is what should rotate the lever clockwise. It also looks like part 43 engage the rack for the metering pumps. The second picture is an internal shot of the part 43, I put a scope into the engine to see what was going on. If you look it appears to have wire wrapped around it, and it not the same thickness as the spring 41 you can see in the picture.

I attached a link at bottom to a video I record of part 43 rotating, I hope you all can view it, its MPG4. It will allow you to down load the video to your computer. If you look at the video, it appears like the spring is not moving so it not attached to the level 43 as I think it should be. There is also spring 38, the drawing does not show where that is attached, that could be the wire seen on lever 43.

Let me know what you think. Could anyone share a good picture of proper connection of spring 41 and lever 43 should be. As said I am thinking this was not put back together properly when it was worked on.

TIA

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[Ray70]

When you were working on reinstalling the metering pumps correctly did the lever pins on all 4 move freely? ( the pins that engage the fuel rack )
And if you removed all 4 metering pumps at once, did you notice the fuel rack always springing itself all the way to the right ( rear of the engine )?
If the rack isn't pulling the metering pumps to the full fuel position with the engine stopped, then spring #41 isn't your problem.
All that "trip mechanism" on the lever simply allows the fuel shut off solenoid to pull the fuel rack forward to the "off" position despite the governor trying to force it fully open.

Do you have all 4 metering pumps bolted down fully?
If they are not bolted down all the way the lever pins will rub on the underside of the block, causing them to bind up and the rack / fuel lever won't move.

It sounds like your rack is binding up for one reason or another. Either a sticky metering pimp lever or some other issue with the governor or the rack etc.
The red silicone sealer on the timing cover is not from someone replacing the metering pumps, it's probably from someone poking around in there trying to figure out what's wrong with the governor rack, or someone poked around an caused a problem with the rack.....

 

[Maestro]

I did confirm all the meter pumps fuel adjustment pins moves freely on all 4, as I said they are all new, there is no signs of any wear on the bottom which engages the cam shaft.

When all the meter pumps are removed the fuel adjustment rack does move freely, but it does not spring to the (right) back of engine it will eventually move. I can move it by hand and you can tell it has some spring tension on it. It will only move once I manually rotate the start/stop lever clockwise to the back of the engine.

I found a video on how to properly install the metering pumps and adjust them, I followed that and when I move the start/stop lever as best I can tell the adjustment pin on the metering pumps are moving back and forth as you would expect. I made sure they were fully seated and they all had the 3 spacers between the block and black ring.

I am starting to think I need to remove the gear cover, since someone was definitely in there at one time and may have messed something up. Do I have to remove the radiator or could this be accomplished by take the fan, belts and hoses off.

 

[Guyfang]

Is this the same generator set you are trying to fix in the thread?:

MP-803A - Will not Crank from S-1

 

[Ray70]

Welcome back Guy! Yes he started a new thread to discuss additional issues he found.

Yes, you definitely will be taking the gear cover off. Since the rack does not spring back on it's own the metering pumps and the fuel lever will never move to the correct position. I suspect something within the governor mechanism or linkage ha gotten disconnected or jammed up. Everything you need to inspect is under the cover.

 

[Maestro]

First, Sorry for any confusion between my two different posts I have made. Yes same generator two different issues, Original issue is fixed all electrical as far as I can tell.

I spent some time on the unit this weekend. I was originally trying to avoid opening the engine up hoping for a simple obvious problem. As @Guyfang pointed out the lever is not original and someone did some nice machining to make it.

I will correct one observation the metering pump rack does move freely when the stop/start lever is in right most position (rotated clockwise) I can move the rack to the left (front of engine) and it will spring back to the right on it own not catching or binding on anything.

However, the stop/start lever does not freely rotate, it is binding not sure if it is internal or the shaft, I did spray penetrating lube between the level and bushing onto the shaft and cycled it a couple of times and it moving easily but still binding. I think you all would agree the lever should easily rotate and not require any effort. If this is binding up this needs to be fixed.

I did locate the replacement lever for this unit, it is the exact part number called out in he manuals. From what I can tell this kit contains the Lever as well as all the internal parts with the springs. Can someone confirm this for me.

MEP802A-MEP803A LEVER KIT Onan 186-6132 ⋆ Green Mountain Generators

MEP802A-MEP803A LEVER KIT Onan 186-6132

greenmountaingenerators.com

Is there any other place to get these parts other than green mountain, they seem to be the most cost effective place.

I am assuming to replace this and remove the bolt holding it in place the cam timing gear has to be removed? can someone confirm this. Is there any words of warning or advise before doing this work.

If I am going to open up the gear cover I think you all would agree to replace the gasket and to use RTV to seal thing up?

To remove the crank pulley, do I need a puller or does it come off once the bolt is removed?

Thanks for all your help.

 

[Guyfang]

Thanks Ray. Glad to be back. 45 old ladies ans 6 poor old men on a bus. Had I not had hearing problems before, I sure would have by the time I got back.

You can place a parts wanted thread, here in the Forum. Some folks have extras or are parting out set. Sometimes you get lucky.

If I remember right, the bolt holding the pulley is a Left hand thread. I seem to remember someone just like me breaking a socket because he didn't read the book a long time ago.

 

[Ray70]

On the pulley, usually it will pull right off, no puller required.
The bolt is indeed left hand thread.
The fuel shut off lever is 2 pieces held together with a bolt through the inner end.
When you reinstall the new lever be sure the 2 halves are indexed together properly before you tighten the bolt down.

 

[Maestro]

Thank you for all the advise? I am ordering the parts since I am not sure what will be needed and just better to use new when I can.

Okay, righty loose on the bolt, I was about to read the service manual to see if anything I should be aware of.

 

[Maestro]

I do have general question, as I stated in a my other thread, I have limited experience with Diesel Engines, done plenty of work on gas engines.

When I tried starting the engine and before knowing there was an issue with the metering pumps not being installed properly and then the lever issue. I never really got the engine running. It would start and run on starter fluid, mostly white smoke hardly or no dark smoke which indicated no diesel getting to the cylinders which lead me to the pump issue.

From what I have learned. if the stop/start level is fully clockwise rotated and the metering pumps are working properly the engine should start, correct?

As I said the lever will not rotate on its own to the right. If I manually move it I am assuming the engine should start and run.

I have not attempted to start the engine since I was not sure if it would get into a runaway situation. I was sure of the full function of the stop/start lever does it need to move freely, Since the stop/start solidness arm has a slot in it, I was thinking the lever was free to rotate back and forth as needed.

Should I just put the lever in the start position and try getting it running to prove it will run before opening things up?

Is there anything i should be concerned about if I do this?

 

[Ray70]

IF the binding lever is the only issue than manipulating it to the right should allow it to start.
But if there are other issues going on with the governor linkage you could end up stuck at full throttle, so I'd have the air inlet tube removed and be ready to block off airflow just in case!
Note: blocking the air may not kill the motor completely because the engine can suck a little air from the crankcase breather tubes that connect from the rocker cover to the intake ports, allowing to to still run at a very low, smokey idle.
If something happens, and blocking the airflow leaves it running slowly, shut off the electric fuel pump and it should stall out fairly quickly

 

[Ray70]

Sorry, I missed up above where you asked about the radiator, no you do not need to remove the radiator yet, just the fan, which is also a left hand nut!
Only reason to remove the radiator is if you end up needing to pull the governor rack out, otherwise leave it in.

 

[Maestro]

Sorry it been a while, have been traveling and have not had time to work on the unit.

I started to reassembling the motor after removing the injector pumps. I wanted to see if I can at least get it running before trying to address the issues with the stop/start level and disassembling the front for the engine.

After being very careful putting the injector pumps back and verifying they were install correctly. I notice when putting in the injectors and before tightening the hold downs I could easily rotate one injector pump and watch the other three rotate. This told me I had them installed correctly. At first I though i had stuck push rod for the injectors since one would not move down and made it difficult to install the injector pump. Then I realize i need to rotate the crank, what was odd, i had to rotate it 180 degree before the push rod would go down.

I would definitely recommend turning the crank to make sure the push rod for the each injector pump is at their bottom position before installing.

Another observation I notice installing the injector pump, the spring on the fuel adjustment rod does not have enough force to rotate the pin on the injector pumps. Even when I move the stop/start lever to the start position (clockwise and to the right), the injector pumps levers do not rotate to the start position. I know the engine will not start unless the lever on each injector pump rotates.

Here is my question and it how does the governor work in relationship to the fuel adjustment rod.

Once engine is turning over with the starter motor, will the governor engage and then push on the fuel adjustment rod to turn each of the injector pump fuel levers. Or should there be enough spring force on the fuel adjustment rod to move the injector pump lever without the engine rotating.

If those injector pump levers do not rotate to the start fuel position I will not get it running which means I just need to get inside and see what is happening. I was just hoping to prove it will run before doing a significant amount of work.

Can someone explain how the fuel adjustment lever work in relationship to the governor and the stop/start level. I have seen a few example when the Fuel Stop Solenoid is removed from the Stop/Start lever the lever will rotate on its own. You need the solenoid to keep the lever in the stop position.

I got some of the parts I needed to rebuild the front gear cover except the stop/start assemble, I want to see what I was dealing with before ordering it or any other parts.

 

[Ray70]

If you take the fuel stop solenoid out of the equation, the spring should force the rack fully towards the rear of the engine.
When the motor is off and solenoid disconnected or retracted electrically, the rack will spring rearward to the full fuel position.
Once the motor starts the governor weights will immediately attempt to pull the rack forward some to slow the revving engine down to the desired speed.
If the rack will not spring all the way rearward to the full fuel position on its own, the governor will not "push" it back once the motor is running.
If the rack will not go to full fuel on its own then there is something binding within the mechanism.
It could be a pump that is sticky or possibly 1 pump pin is not engaged into the rack correctly.
Keep in mind that all pumps must be tightened down all most against the block otherwise the pins will rub on he underside of the block, causing the rack to bind up.
Up above where you mentioned you have seen instances where the fuel lever will rotate on its own with the solenoid removed, that is actually the correct operation. The fuel solenoid does not PULL the lever forward. All the solenoid does is PUSH the lever off when the solenoid is disengaged and it "gets out of the way" when it is energized, allowing the spring to pull the fuel lever, rack and the levers on all 4 metering pumps into the full fuel position.