Engine blew white smoke died then generator

Did someone put gas in your tank?

No... Noone touched for 200 miles as was. Unless they did it in dark... Unlikely just drove another 100 miles since overnight

If your fuel tank is low and you’re on an uneven surface it’s possible you have sucked air from fuel tank or bad fuel (water or other contaminants) from the bottom of the tank. It’s possible your gauge is off a bit. On my diesel motor home my gauge will show a quarter tank one minute and the “E” shortly after.

See if you can get some fuel delivered and try bleeding the system. If that don’t work you’ll have to have it towed in.

A tow may be required but drain any water from the fuel filter if so equipped. Replace the fuel filters. You may have debri in the tank that got stirred up with the sloshing with the low fuel level and the hill. If you don't have fuel filters buy at least 2 sets and hopefully you can get to some help.

Save the old filters to cut open and inspect which may help with determining any required tank cleaning.

My gen intake is set to suck air at about 3/8 level which is common to prevent running dry for the engine. Low level light is about 1/4 tank and E on the gauge is about 100 gal for a 130 gal tank. It's a shallow 7.5' cross tank and all of this is designed to help prevent sucking air which causes a diesel to immediately stop.

Also have you been doing any fuel maintaince for algae? Might be a issue.

White smoke is typically the result of one of a number of bad things, however there is only a couple of things that could afflict 2 different engines.

That is water in the fuel, enough to overwhelm the fuel water separator on the rig’s engine.

It’s hard to believe that’s the issue though considering how high the pickup for the genset is.

Smoke is black or gray
Steam is white
"White Smoke" suggests one of two thigns
Water got into the fuel bad enough to become significant
Blown head gasket.

The fact it happened on both the MAIN engine and the Generator in short order suggests water in the fuel tank. lots of it. Now that is fairly easy to fix.

On the other hand.... it could be EXPENSIVE if I'm wrong.

White smoke suggests water. Drain fuel from your primary fuel filter and collect the contents in a clear container…the primary filter is likely on the left side of the engine compartment and has a drain on the bottom. The secondary filter is on the passenger side of the engine… remove the filter and collect the contents…any water? Turn the key on for 30 seconds 2 times after draining the primary and 5 times for the secondary… this will replace the lost fuel in the filter.

The generator doing the same thing doesn’t make sense if it’s water as the pickup is not on the bottom of the tank. Your fuel pickups are on the right side of the tank…was the rig leaning to the right more than normal when this happened?

Well the gauge worked really well for $2,500 mi and then I drove 350 miles and it still said full so I did check the level and it was probably at one half I'm guessing but maybe more because I found the source of the problem.

So I drained the water separator once I found where that was and a bunch of black stuff came out like pepper looking almost only I couldn't tell the texture at the time but it was about the size of that ground pepper that you can grind yourself. There was no water in it I could tell that but basically it's like algae I guess sludge but they call it algae basically.

So the dealer where I bought the RV said oops we forgot to change the filters we were in too much of a hurry. I wish they would have changed the filters so God knows you know how long that's been there like that I don't know if it's from the filter or from the tank.

So I stuck an awning stick in the 200 gallon roughly diesel tank and black came off on the edge when I scraped the metal awning thing against the inside of the tank nothing came out of the tank unless I scraped it but there was black on there and it wasn't real thick or anything it was almost like an ink pen that leaked and how you would smear that maybe.

So in order to get this to drive I actually had a spare water separator filter or whatever they call it in the RV. So I got some Diesel from the road crew nearby and fill the new one up so that it would prime easier. I turn the ignition key on but didn't start it and cycled it after about 30 seconds about five times and what I think was priming the water separator and perhaps the fuel filter. Then I turn the engine over and it started right away. I did not change the fuel filter even though I have a spare one of those that's even harder to get to. So it looks like the tank goes to the water separator then the fuel filter and then the pump and perhaps the filter finally got so clogged that it wouldn't run. That or the fuel level is lower than I think and it was picking up some of that algae from the tank. I don't know for sure but wouldn't the algae be the same in the tank and I'm calling it algae it's sludge or whatever grows there in the diesel tank I guess but wouldn't that still be there no matter the fuel level so cuz it's picking up from the bottom I would assume so whether it's full or half full or one third full I mean I get it when it's got no fuel left that would be bad but it never got anywhere near there it certainly between a third and 2/3. Maybe the perfect storm of sloping down hill in some way affected it with that slope. But clearly the filter had sludge in it and it looked like probably 8% of the fluid was that sludge coming out of the filter so maybe that clogged the filter to the point where it choke the motor out not sure why it belched white smoke when that happened but maybe cuz it was struggling I don't know or it's burning sludge although I get the feeling that the sludge never made it past the water separator and that contributed to perhaps why I think I had more fuel than a half a tank for sure in so many miles of the poor motor was probably starved for fuel the whole time.

What tells me it's more the tank than maybe a bad or dirty filter is that the generator did the same thing now I don't know what the odds of that are I mean what would the odds be that the engine would die due to algae at the exact same time the generator would when they're two different filtration systems sucking from the same tank. So perhaps you know maybe everything swallowed a bunch of sludge at that one time the thing is I tried to start the generator and that thing hadn't run in days... So it is a bit of a mystery there was no water and there's sludge but I just can't quite figure out why the generator would die at the exact same time when I tried to start it basically it did the same exact thing.

Long story longer I pulled into town about 50 miles later possibly tomorrow getting another filter just so I can have it until I can get the thing home and take care of it when all of a sudden it won't go any faster than about 20 mph. I look down in the transmission says two on the little Allison control board. I thought it was dying from that sludge but as it turns out the transmission was stuck in second gear I guess out of six speeds so I pull up to Walmart where I'm going to try to figure out what the heck's going on and the truck won't go into neutral I put the air brake on and it stops it but as soon as I release that the motorhome starts moving being in second gear. I took the control panel off and unplugged the transmission control maybe trying to reset it I don't know and then I plugged it back in and it still had the same thing a 2. The transmission is an mh4000 Allison 6 speed from about 2006. So I do the diagnostic check for the fluid or whatever for the transmission level and it flashes a code that is 56 which indicates that it needs to be in neutral of course we know it wouldn't go in neutral. So I turn the truck off which I hated to have to do at that moment and then I turned it back on and then the two Ns flashed. I tested the oil level for the transmission and all this Allison stuff refers to the transmission fluid as oil by the way which I think is kind of dumb but I guess it's a form of oil. It said that it was four quarts low. I did find a small dripping leak that would leave the size of a silver dollar after about 5 min of running park somewhere so I can only imagine how much it's leaking while driving that's probably where the four quarts went since my understanding is these things do not burn transmission fluid. It has some special fluid called TransSynd. Apparently you're not supposed to mix dextron 3 with this type of fluid which is a full synthetic I guess some kind of special ****. I probably could because it's already a hundred thousand miles into the 150,000 service interval so I suppose with dexron 3 which goes to 50,000 that would put it at the service interval anyway. But I'm not 100% sure that it doesn't do something else if you combined extra on three with this TransSynd. Of course there's nowhere that sells it so I'm not sure they have Lucas transmission fix cuz there's that little bit of a leak I'm not sure where it's coming from I figure okay what could have hurt with 4 quarts of that so I'm going to call that company tomorrow and see if that **** will work in it if it's next time three anyway and this is something that's supposed to work with everything Lucas oil transfix maybe I'll just use that if I can't find the **** fluid. Anyway that's a whole other problem that showed up and I don't really know if the transmission is going to even work after I do this it went to neutral after I shut it off and it ran perfect all the way up until I got into town and all of a sudden it wouldn't go out a second gear I don't know why so I'm not too sure like it didn't even act up you don't just usually have like a catastrophic transmission failure like that I don't think especially when there's no symptoms and it was working perfectly fine and it was like nothing that even happened I don't know if it's because of the four quarts low maybe it protected itself you can't tell it just has 2 displayed.

Back to the fuel problem. So I took the filter off of the Onan 12.5 KW generator which is a Cummins. Of course there's no fuel filter in town for Cummins generators in Cortez Colorado. So I tried to actually make my own filter but I could never find a quarter
Inch to like a 5/16 Barb then I could just put an inline fuel filter in there of some kind you know with a 5/16 fuel line couplings etc. So I filtered fresh diesel through it filled both sides and took an air compressor and blew it out at 100 PSI blowing from the engine fuel pump side to these supply side that way I don't force any contaminants into the filtered side. Did that about 15 times filled it up and blew it out then I filled it up one more time reinstalled it and the generator started right up. So who knows I mean that's just both filters to that point at the exact same time and they're generators hardly ever run so you tell me I got no idea like what's going on with that or the transmission honestly I hope it works tomorrow I'll keep you updated I don't I guess I need to post the transmission issue in a separate thread.