Mep802a starts then shuts off

[Bassfishin114]

Recently acquired a mep802a and have been working through a few things to get it going. I found that the shut off solenoid when cranking pulls back but once the engine fires up and return the start switch to run the solenoid returns to the off position. This causes the engine to shut back off. It I hold the solenoid it will stay running. I replaced the solenoid and still having the same problem. Just trying to see where I should start. Start switch? Relay? Is there a specific wire at the switch panel that should be providing power to the solenoid?

 

[Light in the Dark]

Have you had the batteries tested? Does the machine make power by the gauges or is it shutting down before they register?

 

[Bassfishin114]

Have you had the batteries tested? Does the machine make power by the gauges or is it shutting down before they register?

Batteries are both brand new at about 12.8 volts each. I don’t think It is registering on the gauges at all before shutting off. When I hold the solenoid open to run the generator all of the gauges appear to be working.

 

[rickf]

Oil pressure switch?

 

[Bassfishin114]

Oil pressure switch?

I guess that’s possible. I just think it would run a bit before the switch kicked it off. It’s instantaneous as soon as I switch from crank to run. Is there power going to and from the oil switch? Then I assume it would go to the start switch. Could I just jump the oil pressure switch?

 

[Light in the Dark]

You can make a dual male ended cable to jump the leads together that are coming off the switch, to take it out of the equation.

 

[Light in the Dark]

Do you have the -24 TM for this machine? It has a flow chart of troubleshooting any issues you can face. An example related to just the engine characteristics:

 

[kloppk]

Are there any fault lamps illuminated on the fault monitor when it shuts down?
Have you done a lamp test to verify all the lamps work?

 

[Daybreak]

Do you know how to start a MEP generator?

 

[Guyfang]

Kurt and Daybreak are asking good questions.

If you do not hold up the S1 long enough, that's the kind of fault you get, (Daybreak)

And if there is a fault with the oil press. switch, the idiot light should come on. So, start the set, Hold S1 up longer then 30 seconds. Let go. If it stops, start it again. Push up the S7, (Battle short) switch, and let go the S1. What happens? Do you get an idiot light? (Kurt)

 

[Bassfishin114]

Kurt and Daybreak are asking good questions.

If you do not hold up the S1 long enough, that's the kind of fault you get, (Daybreak)

And if there is a fault with the oil press. switch, the idiot light should come on. So, start the set, Hold S1 up longer then 30 seconds. Let go. If it stops, start it again. Push up the S7, (Battle short) switch, and let go the S1. What happens? Do you get an idiot light? (Kurt)

I haven’t had a lot of time to look at it due to the hurricane that came through today. What I did find is some wires on TB5 that I believe were so I found the wiring diagram and I am going to put it back together tomorrow and see if that solves it. From what I see the wires were for the oil pressure relay and engine fault relay.

 

[Bassfishin114]

I haven’t had a lot of time to look at it due to the hurricane that came through today. What I did find is some wires on TB5 that I believe were so I found the wiring diagram and I am going to put it back together tomorrow and see if that solves it. From what I see the wires were for the oil pressure relay and engine fault relay.

After attaching the wires I turned the start switch and the low oil pressure light came on. Followed troubleshooting and clean the sensor. After installing it the oil pressure light does not come on but still no crank. I started looking closer and realized that at some point someone cut one wire on the oil pressure sender. I assume I will need another sensor but I don’t any other wires for the third wire to connect to. Is it just a ground?

 

[kloppk]

Only 2 of the 3 leads are used on the OP switch.

 

[Guyfang]

Even if the LOP, Low Oil Pressure switch is bad, the set should start. The S1 function, in the start position, bypasses the LOP, along with several other safety switches. So when a set can start, and the LOP is bad, you simply put the S7, (Battle short switch) in the up position, and the set should run after the S1 is released. So, if the gen set will not even start, the LOP is NOT the problem.

 

[Guyfang]

Do you have the -24 TM for this machine? It has a flow chart of troubleshooting any issues you can face. An example related to just the engine characteristics:

View attachment 883986

Please answer the above question in red.

Open to read comment.

 

[rickf]

The ORIGINAL post said it would start and then shut down when switch was released. I also noticed he now says it will not crank. Getting confusing.

 

[Bassfishin114]

The ORIGINAL post said it would start and then shut down when switch was released. I also noticed he now says it will not crank. Getting confusing.

Originally it would crack then shut off almost immediately. That’s when I found wires not connected on the TB5 row of connectors. After figuring out where the wires go I now have no cranking.

 

[Daybreak]

Howdy,
Start in this thread.
2nd post has quick links for some info
3rd post has links to the manuals.
MEP-802A MEP-803A Filters and Parts | SteelSoldiers

 

[Guyfang]

I wish you luck in repairing this gen set.

 

[rickf]

In your typing you tend to leave out entire words so that makes following your conversations hard. But from what you have said like the part about the two wires on the o/p sensor and asking if it were just a ground makes me wonder if you have even looked at a wiring diagram? And if not how did you rewire the ones that were off? Next question is do you know how to follow a wiring diagram and actually convert the picture on the paper into what you see in the machine? If you do not follow the troubleshooting procedures to the letter from start to finish you will never find the problem. You absolutly cannot skip any part of the trouble tree! Personally I have no experience with this machine, but some of the people answering you have a LOT of experience with them and you are not paying attention to what they are telling you. You are jumping around making your own "assumptions" in between them trying to give you solutions. You will find out real fast that this is the fastest way to lose very good help!