MEP 802A Fix-up Thread

[CallMeColt]

Here are some pictures of the finished work. I meant to upload them sooner but had family visiting. With the bad weather, my internet connection has been very slow as well.

 

[CallMeColt]

Did a good 100% load test for a little over an hour until I had it shutdown with the no fuel light.... even though the fuel level was more than a half tank. Brand new float switch! I also noticed lot's of smoke... see the attached picture. Besides the no fuel shutdown, it ran fine. Noticed a tick as well, but it turned out that one of the cheap battery hold downs that I got broke & that was the cause. Was puffing a bit if the same colored smoke as well from the exhaust... thinking it just needed to burn off some crap.

Float is brand new. I tested it fully when I had everything out. I'm tempted to just cut that wire & not deal with that anymore as it seems to be a never ending issue. I am going to adjust it a bit and see if that makes it go away.

I'm thinking the smoke is burn off from all the fuel that was spread around the inside when the return lines let go & it was sent everywhere from the fan. Maybe some that was soaked into the exhaust wrap. Also, the radiator may still have some fuel in the fins. What do you guys think?

 

[Light in the Dark]

I'd recommend not truncating any wire in these sets. They all have good, definite purposes for being there. So the light comes on for two reasons:

You have no fuel
The set THINKS you have no fuel

As you say you have fuel in it, great! So that leaves two components... the fuel sending unit (ie float in tank), and liquid level switch (on rear fender). So on the float, sometimes they stick... if yours is new, it would hopefully not be the case. But components have been known to be DOA, especially when they have these little internal contacts. The level switch can fail too. There are testing procedures for both in the TMs.

For now, while not advisable for long term use, get the set going and flip the battle short up... with any luck the light will illuminate, but the set will continue to run and ignore the 'false positive' message.

 

[CallMeColt]

I'd recommend not truncating any wire in these sets. They all have good, definite purposes for being there. So the light comes on for two reasons:

You have no fuel
The set THINKS you have no fuel

As you say you have fuel in it, great! So that leaves two components... the fuel sending unit (ie float in tank), and liquid level switch (on rear fender). So on the float, sometimes they stick... if yours is new, it would hopefully not be the case. But components have been known to be DOA, especially when they have these little internal contacts. The level switch can fail too. There are testing procedures for both in the TMs.

For now, while not advisable for long term use, get the set going and flip the battle short up... with any luck the light will illuminate, but the set will continue to run and ignore the 'false positive' message.

I have put two different & new float switches in. I haven't had time to rip it apart again... mostly because I don't want too! I've already spent way to many hours on it. I'm hoping that there is a stupid reason for it & I'll find it quickly & be done with it. I do want everything to work correctly & as it should.

The no fuel float I can't see why it's really required. Nice to have, but no other generator units use them that I have had. I'd guess it was just put in as a requirement when the military was looking for a new design. On some diesel engines without a return line, purging the air is a HUGE PITA... MPE 531A for example. That may be why they want it as a blanket requirement. Also maybe to avoid some frequency drop when the fuel is about to run dry for sensitive equipment.

Wish me luck. I may dig in again this week if I don't have long work days.

 

[CallMeColt]

I ran it at 110% for 3 hours & the light didn't come back... strange. Makes me thing it may be the switch itself on the fender randomly sticking.

One thing I noticed... The screenshot on the left below was one I found online. The picture to the right is of my generator. I noticed the different placement of the wires. Everything seems to run fine & that is where the wires were when I got it.

 

[Guyfang]

I have put two different & new float switches in. I haven't had time to rip it apart again... mostly because I don't want too! I've already spent way to many hours on it. I'm hoping that there is a stupid reason for it & I'll find it quickly & be done with it. I do want everything to work correctly & as it should.

The no fuel float I can't see why it's really required. Nice to have, but no other generator units use them that I have had. I'd guess it was just put in as a requirement when the military was looking for a new design. On some diesel engines without a return line, purging the air is a HUGE PITA... MPE 531A for example. That may be why they want it as a blanket requirement. Also maybe to avoid some frequency drop when the fuel is about to run dry for sensitive equipment.

Wish me luck. I may dig in again this week if I don't have long work days.

All of the modern gen set the military has, have this function. As you know, its to prevent the set running dry. Nice function to have when you are standing in the rain.


One thing I noticed... The screenshot on the left below was one I found online. The picture to the right is of my generator. I noticed the different placement of the wires. Everything seems to run fine & that is where the wires were when I got it.


There is, or was markings on the switch. Also, you can look at the schematic, then ohm it out. Never trust what someone else has done. Check it. then you KNOW its right.

 

[Light in the Dark]

I wouldn't surge load it to 133 like that. Its fine to ask it to make that power for durations, but you may be better served ramping it up to that load level incrementally.

 

[CallMeColt]

I wouldn't surge load it to 133 like that. Its fine to ask it to make that power for durations, but you may be better served ramping it up to that load level incrementally.

I wouldn't do that often, but I was pushing it hard to clean it out & figured I'd take a video.

 

[CallMeColt]

All of the modern gen set the military has, have this function. As you know, its to prevent the set running dry. Nice function to have when you are standing in the rain.


One thing I noticed... The screenshot on the left below was one I found online. The picture to the right is of my generator. I noticed the different placement of the wires. Everything seems to run fine & that is where the wires were when I got it.


There is, or was markings on the switch. Also, you can look at the schematic, then ohm it out. Never trust what someone else has done. Check it. then you KNOW its right.

I found the TM .pdf files I had to suck. Went on here & found the thread where you shared them & they're much better. The ones I had couldn't be searched & I think pages were missing. This is the reason why I ended up asking questions about stuff that's in there... because I couldn't find it!

 

[robson1015]

Excellent post, I especially like the instructional vids. Would have loved to see the ultimate well nut video. Keep up the good work.

 

[goat4hooves]

I ran it at 110% for 3 hours & the light didn't come back... strange. Makes me thing it may be the switch itself on the fender randomly sticking.

One thing I noticed... The screenshot on the left below was one I found online. The picture to the right is of my generator. I noticed the different placement of the wires. Everything seems to run fine & that is where the wires were when I got it.

View attachment 746367View attachment 746368

Double check the wiring with a meter to ensure they are routed correctly. It is surprising how many wires can be routed incorrectly.

 

[CallMeColt]

Excellent post, I especially like the instructional vids. Would have loved to see the ultimate well nut video. Keep up the good work.

I should have done it with the improved well nut that I ended up putting in. I was so focused on the work & somewhat fed up with working on it, the last think on my mind was to record something. A lot of the work was done at night as well. When I open everything up to try & figure out the phantom no fuel shut off, I may make a video just explaining it & show the part numbers, etc.

 

[Demoh]

... When I open everything up to try & figure out the phantom no fuel shut off, ...

I was getting this with one of the generators I hauled up to panama city after Hurricane Michael. Turned out the fuel level box that the floats go to had a loose connection, and I ended up running a small zip tie around all of the connections in the set to keep the 802 from working them loose over time. I swear that 802's unbalanced operation can put a serious strain on the harness. (during 120 hours of running we had to repair broken wires to the oil pressure switch 3 times because they fatigue and break)

 

[CallMeColt]

I will just remove the box & see if there are any issues inside of it. I like the idea of using small zip ties on the connectors as well.

Haven't had a chance to open it up. I just finished going through the front axle on my truck. That was a learning experience.

 

[CallMeColt]

So, I took the panel off & checked all the floats & switch for the No Fuel shutdown. All tested as they should. I checked to be sure the tank didn't have anything big moving around in it that could hit the float. The float is free. The connectors are all tight & I added the zip ties as suggested above. I'm at a loss! If the problem pops up again, I'm just going to disconnect that float.

 

[Guyfang]

I would suspect A9 if everything else is in order.

 

[CallMeColt]

I would suspect A9 if everything else is in order.

I've put two new ones & a had the old on in there! I cycled the float a bunch of times to make sure it wasn't crazy & it did what it was supposed to bot on the meter & at the panel.

 

[Guyfang]

Whats left, besides wiring?

 

[CallMeColt]

Whats left, besides wiring?

I have no idea. I'm hoping that I had some sort of lose connection. My last thought is that there's something in the tank that I left in there when I worked on it & I can't see it at this point. Will keep using it until the tank is empty & put a camera in there to be 100% sure. If the problem keeps coming up, I'm just going to disconnect the wires for the no fuel shut off. Not sure what else to do! No spending another $40 on a float again.

 

[Guyfang]

Is the float adjusted too low? Therefore vibrations every once in a while cause the float assy. To shake around too much?