MEP-802A No Response to Control Panel Functions Including Start Switch

[NBA89]

Hi all,

New member here! I was following CDR's journey sourcing his no start condition on his MEP-802A which led me to create an account and describe my own issues. The unit is low hours ~600 and appears to be in excellent shape. I've charged the batteries, but get no response to any input at the panel controls. This includes, preheat, gauge lights, prime, start, etc. Nada. However, when I engage the dead crank switch, the engine tries to crank. I'm guessing it's been sitting and drained so long that without fuel prime, it won't start via the dead crank. I've filled it with new oil, diesel fuel, and full batteries. I see a wire tracing journey in my near-future. Along with going through troubleshooting procedures in the TM, does anyone know of a good place to start or a simple fix to this problem? I should also note that yes, the emergency stop button is disengaged

 

[DieselAddict]

Did you pull out the E-Stop switch and check that the circuit breaker behind the control panel was pushed in?

Also, have you read any of the manuals about how to operate it?

 

[NBA89]

I did mention that I pulled the emergency stop button out and as far as I know the circuit breaker was pushed in. I opened the panel to check behind it and everything looked intact, connections-wise. I've owned an -831, -006, and -005 so I'd assume they all start similarly. Is there anything special to starting an -802? It's just odd that it's not getting power to any of the circuits with full batteries...

 

[DieselAddict]

Time to break out the manual and see if you have power in all the right places.

 

[craigc]

Welcome, I'm also a new member here. My best advice is the KISS method. Your correct in reading the TM for your equipment. If nothing seems to work on the 24VDC side check the power supply, ie the battery voltage, the fuse/breaker for the 24VDC side of things. Even though your batteries show charged what happens to their voltage when you activate the dead crank switch. Do the batteries fall on their face when a load is put on them?

There is many excellent people on this site that have helped me and many others. Your problem is likely a simple one, read the TM's, follow the TM's and I'm sure you will find a solution to your problem AND you'll learn
Then you can help others too

We won't leave you and we will always help you, check the stuff above and let us know what you find and we can go from there. I bet you'll figure it out

 

[NBA89]

Thanks craigc, I appreciate the reassurance. I'll let you guys know what I find.

 

[craigc]

Your more than welcome, Dieseladdict, guyfang and a bunch of others here are WAY above me in regards to these gensets and they are really great people always willing to help.

Oh and check that you have the correct relays in the correct spots, some people ended up with relays in the wrong positions and or wrong types such as 24VDC relays in a position that should be 120VAC relays.

 

[DieselAddict]

Thanks for the kind words Craig,

Check out this post and download the diagram I've been working to clean up. It may make tracing circuits easier.

http://www.steelsoldiers.com/showth...-restoration&p=1933214&viewfull=1#post1933214

 

[craigc]

Dang!!!, That is perfect. thanks a ton for the work you and others put into that diaphragm. This is what I love about this site. Really smart and helpful people helping those of us that are maybe not so much

 

[Guyfang]

Hi all,

New member here! I was following CDR's journey sourcing his no start condition on his MEP-802A which led me to create an account and describe my own issues. The unit is low hours ~600 and appears to be in excellent shape. I've charged the batteries, but get no response to any input at the panel controls. This includes, preheat, gauge lights, prime, start, etc. Nada. However, when I engage the dead crank switch, the engine tries to crank. I'm guessing it's been sitting and drained so long that without fuel prime, it won't start via the dead crank. I've filled it with new oil, diesel fuel, and full batteries. I see a wire tracing journey in my near-future. Along with going through troubleshooting procedures in the TM, does anyone know of a good place to start or a simple fix to this problem? I should also note that yes, the emergency stop button is disengaged

OK NBA! Now you are ready to start. You have the CLEAN schematics, (thank you DieselAddict!!) and with the troubleshooting you can get started. If the engine turns over with the S-10, dead crank, batteries are not the problem. The Dead crank's function is not to start, only to turn over the engine, WITHOUT starting it. Plenty of good reasons for that, like bleeding the fuel system to the injectors, or adjusting the Mag Pickup.

So if it cranks with the S-10, you have learned a lot. Now, no input to the controls. Look at your manuals and schematic. Open the control panel. Find the MT-4, (battery ammeter shunt) to the right, on the bottom of the control panel. Take your multimeter, (hope you have one) and measure DC voltage. From the frame to BOTH sides of the shunt. You should get approx 24 volts, or what ever your batteries have in them. If you have voltage on one side, and not the other, there is the problem. The shunt doesn't often go bad, but it can. If you have DC voltage on both sides of the MT-4, then look to the left. Find CB-1. It should be pushed in. Pop it out push it in. Then take your handy dandy voltmeter, and measure from the frame to both side of the CB-1. Got power on both sides? Good. If not there is your problem. CB-1.

If you had NO DC voltage at the MT-4, reach up with your hand, on the right side of the control panel, through the small door on the bottom. There are some canon plugs up there. Unscrew them, and screw them back in. Measure again at MT-4. Sometimes these canon plugs are not connected, loose or the pins are burnt off. Pull the plugs down, look into them to see if the pins are there, not burnt off or corroded. These are quick disconnect plugs. They should easily twist on and off. If they feel funny, they could be not making contact.

If you have power to MT-4 and CB-1, look at the middle of the control panel door at S-17, the emergency off switch. Same deal. You should have 24 volts in, and 24 volts out.

I will leave it there. You let us know what you find.

 

[jamawieb]

Make sure your batteries are hooked up correctly and they are truly good. If the batteries are 10volts or under, nothing will work. You said you used the dead crank and it tried to start, that tells me the batteries are the problem. Also make sure your dead crank is set to normal because if it set to anything else it will do the same thing.

 

[csheath]

Also make sure your dead crank is set to normal because if it set to anything else it will do the same thing.

KISS this.

 

[Daybreak]

Howdy,

Video's are worth more than thousands of words.

A quick start routine for a MEP-80x generator
https://youtu.be/5OTZrhhCNmM

 

[Bmxenbrett]

Wait it wont start or it wont crank with the dead crank switch? The difference is huge.

 

[NBA89]

Alright, sorry for the hiatus, but THANK YOU for all the info and the help! Here's what I found out, I have one bad battery that is only putting out 5.5v while the other is holding steady at 11.50v. As for the power to the panel, it's one of those super simple things....turns out the problem was in CB-1. It was popped out and should've been pushed in lol. Guyfang, a special shout out to your help on troubleshooting. I'm going to try recharging the bad battery to just get the unit started. I'll plan on replacing it soon with a new battery. Also, I have this thing sitting on top of a small harbor freight utility trailer. Do I need to drive a ground rod or something before I crank it up and zap myself?

 

[Guyfang]

Its always a GOOD IDEA to ground your set BEFORE running it. As one who has been not just zapped, but hung up on electricity, I will tell you that it brings about a whole new way of thinking. What kind of batteries do you have?

 

[NBA89]

Its always a GOOD IDEA to ground your set BEFORE running it. As one who has been not just zapped, but hung up on electricity, I will tell you that it brings about a whole new way of thinking. What kind of batteries do you have?

I agree with ya! Could you suggest the best way to do it?

 

[Guyfang]

Did the gen set come with a ground rod? Some have them mounted on the right side, down low, on the side of the skid. If not, you can buy one. The military has them, in 3 foot lengths. Normally you drive one section in, screw the next on, drive it in and add the third piece. for about nine feet. Attach the copper wire from the ground stud, to the rod, with clamps. If you look at the -10 manual, Chapter heading "Operation Under Usual Conditions, there should be a drawing of these parts. NSN: 5975-878-3791 is just one of probably 20 NSNs that will get you what you want. Or you can get some wire, at least AWG #6 and hook it to the ground stud and then go to a good ground.

 

[NBA89]

Did the gen set come with a ground rod? Some have them mounted on the right side, down low, on the side of the skid. If not, you can buy one. The military has them, in 3 foot lengths. Normally you drive one section in, screw the next on, drive it in and add the third piece. for about nine feet. Attach the copper wire from the ground stud, to the rod, with clamps. If you look at the -10 manual, Chapter heading "Operation Under Usual Conditions, there should be a drawing of these parts. NSN: 5975-878-3791 is just one of probably 20 NSNs that will get you what you want. Or you can get some wire, at least AWG #6 and hook it to the ground stud and then go to a good ground.

Thanks for the info. No it did not come with a ground rod. Do I need one even though there is no load hooked up to it? If I'm just starting it to run and test, is a ground rod required? I've run my MEP-831A and MEP-016D without getting zapped, though they were sitting directly on the ground with no load. If the -802A were sitting on the ground and not on top of the trailer would it be safe to start with no load?

 

[Guyfang]

The short answer is no, you would not be safe. When producing electricity, a gen set can bite you. One of you guys in the states chime in here. If we were in germany with the thing, I would tell you to ground it to your rain gutter ground system, or someplace like that. Its been soo long since I lived in the states, I cant even remember if you all ground the rain gutters. Or water pipes?