MEP-002 electric diagram/ fuel solenoid problem: was glow plug problem

[redlight]

Greetings,
I have bought and installed a glow plug on my 002 and it now runs well. However I am still having a problem with the fuel shutoff solenoid. It will not retract enough for the unit to run under it's own control. I can manually raise the bottom of the linkage and the generator is making power. I can adjust the speed of the unit with the manual throttle. I have not troubleshooted the problem to find out where the 24 volts come from. I have down loaded the manuals and have looked for a wire diagram and not found it. The plate on the engine is there but I can not read it. I replaced the original solenoid with a test unit but same symptoms. I tested the first one on with 24 volts from the battery and the plunger did not rise.I have not tested the newer one(Used but tested) yet.Due to lack of time working on other projects. Any assistance is very welcome
Redlight

 

[kloppk]

The wiring diagram is in the -34 TM.
It can be found here: https://www.steelsoldiers.com/showthread.php?155935-All-the-TM-s-you-need-to-work-on-the-MEP-002A
The -34 is the 2nd document from the right.
See PDF page 35 for the wiring diagram.

 

[jamawieb]

I've had a couple of units that needed a better ground for the solenoid. I connected a wire from the negative side of the solenoid, to the bolt that holds it down. It may not work in your situation but its worth a try.

 

[Guyfang]

Redlight,

How familiar are you with wire diagrams and you're Gen set? If you have a little experience, or know someone who does, we can check this out.

TIP #1. Use the -34 manual for the MEP-003A. The schematics and wire diagrams are 100% easier to read. There are for this exercise, no practical differences between the models.

The solenoid is called the Governor Solenoid. On the schematic it's K5. Look for it in the top right corner of the schematic. Print out the document below.

View attachment Dok1.docx

For the next step, you will need a helping hand. Someone needs to start the set when you tell them to, and stop cranking, when you tell them so. Open the control panel door. Find TB5. Its a long strip with about a million wire hooked to it. Then find terminal 8 on the TB5. There are numbers over or under the TB, just look closely. When you have TB5-8, place one lead of a multimeter on TB5-8, and the other onto Ground. Set the meter for DC voltage. Have someone try to start the set. What voltage to you get? 24 Volts? If so good. If not, scheisse. But lets assume you get 24 volts. Then look for TB5-9. If you cant find it, go back to bed. Assuming you find it, move your multimeter lead over onto TB5-9, and have someone start the set. Do you get 24 volts? Or not. We will assume yes. Then move around to the K5. It has two wires hooked to it. Using your multimeter, measure from Ground to the two terminals. One shout give you 24 volts, the other should be Ground.

Now you have your homework. Let us know what's what.

 

[redlight]

Thank you all for the response. I earned a degree in electronic engineering over 40 years ago but never used it for the past 30 years. I started out as a biomedical tech /engineer doing component level repairs but morphed into management. Now the field is doing board level or software revisions. I will follow up with my testing during the next week or so. I have down loaded both the 002 and 003 part 34 but still do not see the wiring diagram. The section that Guyfand sent is printed out and makes sense. I think Post #2 on K5 should have 24 volts when the main run switch is closed?
Thanks again
Redlight

 

[Guyfang]

The wire diagram is towards the front of the manual. It's also listed in the TOC.

Roger that, K5 should have 24 volts when the S1 start switch is in the start or run position.

 

[redlight]

Thank you
I did find the wire diagram.
I will test later in the week.
Redlight

 

[redlight]

Greetings,
I went to play on the generator today. I removed the solenoid and retested both the new and the old. they both worked OK, pulled right in.
I reinserted one and it did not activate. I opened the front panel and could not find the right number on the terminal block. While reading Guyfang's instruction I saw again the info about a bad ground. So I put a temp connection on the ground post and to a good ground point . I then restarted the unit and of course the solenoid pulls in fully. Tried it several times and it continues to work. I removed the temp connection and of course it continues to work properly. I let it rest and after removing the temp connection I tired again and continued sucsus.
I have stopped and put it back under cover. Two items come to mind:
A) the secondary ground allowed current to flow and it caused a electrical path that stayed after I removed the second ground.
B) Because I got the unit running and it stayed running, the batterys was recharge enough to allow a full 24+ volts to the solenoid.
Do not care as long as it works.
Now to decide whether or not to keep it. It is big and hard to push around. It needs to run outdoors as I hear about too many CO and CO2 deaths.
Thanks all for the help!!!!!

 

[Guyfang]

Redlight,

You may want to test it several times over the next week or so. Never hurts to make double sure!

Glad it works now, and glad you posted some feedback. Not everyone is so thoughtful.

 

[redlight]

i will
thanks for you help.