MEP-003 Govenor linkage & fuel shut-off?

[Kermit The Frog]

I have one of my MEP-003 generators running but it was hard to start. Once it is running it runs great.

I found if I open the cover that's over the glow plugs and fuel shut-off soleniod then move the governor linkage up a little it starts much easier.

In TM5-6115-585-34 In paragraph 7.3 f. (1) says with the linkage compressed I should have 5 1/2 inches between the ball joints. I have about 5 3/4 between the ball joints. Also, it looks like I might need to move the upper ball joint out a little in the slot to stop it from rubbing the sheet metal beside the soleniod.

In TM5-6115-585-12 Paragraph 4-23 e. says the gap between the fuel shut-off solenoid plunger and the injection pump control arm, with the engine running at full load, should be at least 1/8 inch . Right now I don't have a way to load the engine and with the engine running with no load I have about a 7/16 inch gap. The fuel shut-off solenoid is working. It engages when I turn the switch to start and disengages when the engine is shut off.

It looks like I need to shorten the governor linkage. Also, what should the the gap between the soleniod plunger and the pump control arm be when the engine is running with no load.

Comments and guidance please.

Thanks,

Joe Roach
NW Florida
2 MEP-003's 1 running
1 15 kw Onan
2 6.5 kw Onan
3 5.0 kw Onan
1 3 kw Onan

He who dies with the most toys wins--I'm still here because I don't have enough toys

 

[rosco]

Bump

 

[RichardR]

Well, if nobody else is going to answer this question, I will take a shot at it. My experience with the governor linkage and the shutoff solenoid on both the MEP-002A and 003A is that it's something you may have to dink around with a little in order to get it to work right.

The main problem I have had is that at startup, even when the shutoff solenoid retracts (lifts) correctly, the governor linkage that controls the fuel lever on the side of the Injection Pump can become jammed where the linkage passes through the sheet metal at the base of the solenoid. That causes the IP fuel lever to remain closed and the engine does not start.

The governor arm and fuel control linkage are supposed to pull the IP fuel lever to wide open throttle position (fully up) as soon as the solenoid rises. When the engine starts and its speed approaches the correct governed speed, the governor arm pushes down on the fuel control linkage to partially shut off fuel delivered by the IP, thereby controlling engine speed.

But if the linkage is caught on the sheet metal, or if it is pressed sideways by the sheet metal so that the linkage doesn't slide smoothly to expand/retract by its internal spring, the IP fuel control arm will remain closed, or partially closed, and starting will be difficult. I think you have the right idea that you may have to move the top ball joint of the linkage out to near the end of the governor arm slot to provide enough clearance for the linkage where it passes through the sheet metal.

I don't know that the measurements you quote from the TM are all that critical, but it is a place to start. It is very refreshing to see that you have read the TMs! Not everyone does!

The reason I say that the length of the linkage between the ball joints is not real critical is that you can effectively change the length of the linkage and its clearance at the sheet metal by (gently) bending the governor arm. You can be sure that someone has been in there before you, so there is no assurance that you are starting with a "correctly shaped" governor arm.

The most important result you want to achieve is that the IP fuel control lever rises to wide open throttle position when the solenoid rises at startup, and it is pushed down to fully off position when the solenoid falls at shutdown. In between, when the engine is running, the governor and its linkage should smoothly position the IP fuel control lever to control the engine speed. The solenoid shouldn't ever touch the IP lever when the solenoid is energized during normal engine operation.

You also should be sure that the IP fuel control lever works smoothly and easily from one extreme to the other. Pop off the ball joint, manually raise the solenoid and work the IP lever up and down. If it doesn't work easily, your IP has some varnish in it that needs to be cleaned out. Not unusual in a machine that has sat unused for years. But that's another job.

Hope this helps,
Richard

 

[storeman]

RichardR,

Great response.
Jerry

 

[Kermit The Frog]

Thanks, I appreciate the information. Here is what has happened since I made the post. Because I haven't gotten the fuel tank clean yet I am using a 5 gal fuel container. I bought the two generators in 2009 and because of health problems I haven't fooled with them. Anyway, I put a good dose of Sea Foam in the fuel and got it started a couple of times and let it run for a while.

Now it starts without too much problem. I'm going to check the McMaster Carr catalog for new rod ends and change them.

One of the MEP-003's is going to my daughter in Louisville. She is actually excited about it. I have two girls, one is a CPA and the other is a chef in Nashville, one has a GREAT sense of humor and the other one.......well she's a CPA.

When I get ready to get the other MEP started I'll be much better prepared.

Again thanks for the reply. And I agree with Jerry, Great reply.

Joe
NW Florida

 

[jeepin]

I'm going to check the McMaster Carr catalog for new rod ends and change them.

When you buy the McMaster Carr ones, you will find they are longer on the threaded side than stock. I couldn't use them without cutting them down to match the length of the female threaded part of the stock (plastic) ones. Otherwise the linkage is too long and the engine wont rev to full RPM.

 

[RichardR]

My experience with the ball joint ends of the linkage is that I have only had to replace the bottom one, the one next to the IP. The plastic socket gets old and brittle, and breaks. The current Onan part number for the ball and socket (complete joint) is 150-0939. Google "Onan 150-0939" to find several sources. Prices range from $10 to $20. YMMV.

If I remember correctly (questionable at my age), it's easiest to pop the joint apart, which can be done readily with a new plastic socket, and replace only the socket part of the joint. I think you have to take the IP fuel control lever off -- a PITA -- in order to remove the metal ball part, when the metal ball doesn't really need to be replaced.

And I have never had to replace the top ball joint, just lubricate it. Once again, YMMV.

Regards,
Richard

 

[jayco]

I have a problem with fuel solenoid that is not getting power to it. Where should I begin to trouble shoot?

 

[gimpyrobb]

Jayco, you should start your own thread about your issue and not "cross post" your question in every thread you think might be relevant. This is at least the second thread you posted the question in, your own thread would get the attention it deserves.

 

[TucsonVTXF]

follow the TM as a reference and adjust your unit until it runs the best for you...

 

[dlsacco]

If I remember correctly one of the members on here was making the linkage ends using a 3-d printer... Have a look in the for sales on this forum...

 

[Ray70]

Its JimC fron NJ that makes the plastic rod ends, as well as some other parts. He has them for sale here as well as on e-bay.

 

[Jimc]