Be sure to read all the fine print on the rated towing capacity. IIRC, in the early 2000's RT Chevy brochures gave a figure that (noted in the fine print) was based on driver only, nearly empty tanks (including gas), no factory options (generator, awning), and no cargo. I suspect other B makers may do the same.
Switchback & Ted66, after a _lot_ of work, sweat, money, and a few tears, I traced much of my '99/'00 Roadtrek Dodge's evil wind & curve handling to soft sidewalls on Michelin LTX tires, even in load range E.
I think www.moreheaddesignlab.com _used_ to offer DIY van interior modules for at least the 1st generation Sprinter. I'm not sure he still does, but a quick phone call should answer that. You may or may not get an answer before start of business Monday, considering the holidays.
Don't waste your time looking for "the infamous little black vent tube". That's _only_ on the 2500LP units, not the gasoline 2800. It's a breather tube for the propane regulator.
At 50 hours and 10+ years, your issue is almost sure (95%?) to be a gummed-up carb. Onan says they're not rebuildable; I believe them. They have super-fine internal passages. I have cleaned two of my previous ones, but they weren't that neglected.
Assuming it can be started and run at all, and using all proper caution, break the fuel line somewhere between Onan & fuel tank. Put the 'to Onan' end into a can of 1/3 Seafoam, 2/3 fresh gas. Start it, let it run for 1/2 hour. Stop it, let it sit overnight. Run it 5-10 minutes the next day to draw in fresh solvents. Repeat daily until it runs right or you give up. I succeeded after about a week in one case.
I think your 'house' fuse box is in the converter, right? Your converter's lid/door may contain a diagram of the fuses that tells which holder goes to what, and what size each fuse should be. The fuses may be undersized. Simplistic, but sometimes overlooked.
If it's different fuses that blow at random, you may have a chaffed wiring harness, most likely near the converter. I can't recall either of my RT's wiring layouts from 10 years back, but I suspect they ran the wires in a common bundle leaving the converter, and splitting off as they went close to the various 12V users. I'd start by inspecting that wiring bundle.
Roadtrek _might_ have a wiring diagram on their website. They're better than most RV makers about such stuff, but I dunno how far back their online stuff goes.
Jim, "Leaves don't fall off of trees. They're pushed."
..... When you get done, you'll know why so many mechanics tend to be a bit grumpy. :D
Ain't that the truth... :( What the manufacturers do is select a part that they _know_ dam' well is gonna need replacement sometime in the vehicle's life, probably more than once. Then they hang that part from the ceiling, and build the vehicle around it.
"You can't get there from here" was originally said in a garage, not when giving directions to a stranger as is commonly believed.
Jim, "Yeah, I'm lost. But darn, I'm sure making good time!"
May as well find out what it can do by setting it on 7. It won't speed up col-down time much, tho'. Best to install a remote-reading thermometer in it, so opening it to check won't slow down cooling. Empty, a fairly good operating RV reefer can need 12-24 hours to fully cool down. Fill it with pre-cooled stuff from the house reefer, and only add small amounts of warm stuff over time.
It (the reefer and RV) needs to be darned close to level. You can ruin the cooling system by running it off-level much or for an hour or so.
The noise may or may not indicate issues. My Tiger's much-abused reefer clucks quietly sometimes running on propane, but not noticeably on electric. It cools OK, but not great.
Condition of the door gasket can be an issue with cooling, and Dometic may or may not have one (probably won't, in my experience).
Jim, "Manure occureth."
My Tiger has a manually-lit 3 gallon Suburban WH. When I think there's a danger of it freezing but it's not yet winterized, I just light the pilot light. Leaving it on just 'pilot' all night gets the water plenty hot enough to shower, so I'm sure it's protected from cold.
Mine's easiest to light if I light a stove burner for a moment first.
Jim, "Neighbors... the strangers next door."
Will it always restart immediately? If so, that argues against it being a heat-related. But if it requires a cool-down period, it may sell be heat-related. Both my failures on my current Onan 2800 required at least 5-15 minutes cooling in summer before they'd re-start (fuel pump, voltage regulator).
Another thing often overlooked is the spark arrestor being plugged, but your symptoms don't match mine when that happened (run fine no or light load, chug down and die under load).
Good luck with it.
Jim, "Trying to understand the behavior of some people is like trying to smell the color nine."
Dirt on a belt can cause a ticking sound as the belt articulates on/off of the pulleys. I agree with PaulJ2, you can remove the belt and run the engine.
Or use my friend's technique. He's a 30+ year high-line import mechanic (MB, BMW, etc). He sprays a little silicone spray lube on the offending belt.
I've seen him do it on my Tiger's serpentine belt. The ticking noise went away _instantly_. It's just a diagnostic tool, it won't eliminate the noise for long. But it does no harm (I've run that same belt another 55,000 miles). Now if it's belt noise, you'll know and can decide if it's annoying enough to be worth replacing.
Jim, "Mo' coffee!"
I've lived less than a mile from an Asheville entrance for the past 20 years, driven the length of it twice, and driven much of it more than that. The most scenic part in my considered and hopefully unbiased opinion is between Water Rock Knob outside Waynesville, NC, and Spruce Pine. The 'commuter section' around Asheville is not that interesting, but it does include the park headquarters & visitors' center and about 3 miles on, the Folk Art Center.
I'd suggest finding a CG in Asheville, driving north on the BRP one day, and 'south' (more nearly west) the next.
Jim, "I always thought a gentleman should open a door for a lady, but all she did was scream and fly out of the plane."
Some (most?) Flying J truck stops that have an RV fuel island have dump stations, but charge $10 these days to use them. That may be discounted if you have their fuel loyalty card, not sure. I Think some other brands of large 'travel centers' have them, but not sure. I think Flying J lists the amenities available at each place on their website.
NFS & NPS GC's will allow you to use their dump stations for $5-$10.
Jim, "If you want breakfast in bed, sleep in the kitchen!"
One small town sewage plant I stopped at just told me to back up to their open settling tanks, put the end of the hose over the edge, and let fly. No charge. Worked fine other than not having a fresh water hose to rinse out with. I dunno if management in a larger city might be pickier.
Jim, "Veni, Vedi, Visa... I came, I saw, I did a little shopping."
It's well to remember when dealing with birds, 'specially large ones, that way back in their ancestral lineage is a pretty close link to things like velociraptors and T Rex... ;)
Jim, "Gosh, this dinosaur tastes just like chicken....."
Have you actually seen first-hand any B's (or small C's) first hand yet? I'm not talking about the specific model you're thinking about, but _any_. Seems to me that that's your next logical step. Get in with the SO, close the doors, sit and move around. Stay awhile.
Do be aware that a _lot_ of salesdroids will show you a 'B+'/C when you specifically ask if you can can see a Class B. Happened to me even before the 'B+' term was made up. Partly they don't know the difference, mostly they want you to buy what they have on the lot, right now. If you've got a smart phone, take it and do some on-the-spot research on whatever you're being shown.
Jim, "I tried to microwave instant coffee, and went back in time."
Did the odometers then read full mileage, or reset to zero after 99,999.9 miles? If it's the latter, it could easily be 100k or 200k over what it's showing.
Generator is probably an Onan or a Generac. I don't know if a newer one will fit, but someone skilled (read high $$/hr.) needs to troubleshoot it first. Many generator issues are caused by disuse, and fixes can start about $300 and go up from there. Replacing with a new one, if possible & simple, will run $2.5K > $3.5K, maybe a bit more. A cheaper but hasslesome alternative is a portable on a cargo rack.
Tires should be not over 6 years old, regardless of tread remaining. There are articles on the net on how to read the date code. They're probably 16.5", of which very few varieties are made any more, and freshly-made ones are hard to find.
Check _thoroughly_ for soft spots in walls, ceiling, & overcab; rot caused by water leaks is the death of _many_ class C's.
Finally, if you're in a northern clime, best forget 'living' in it. Cost to heat would be about as bad as rent, condensation & resulting mold might be unhealthy, and water system is very unlikely to be 4-seasons. _Not_ for the unskilled RV'er.
Jim, "Mo' coffee!"
I had a tiny drip onto the toilet lid in hard rains when the Tiger was new. Soon returned to the factory on a trip for a few other small items. They recaulked around the vent (openable, no fan). No fix. It turned out to be one of the rivets holding the plastic cover to the metal crank-up frame. A tiny dab of silicone has held for about 8.5 years now.
Jim, "Mo' coffee!"
Dunno what type of RV they're traveling in. Personally, I think there's a minimal risk to truck stop overnighting if you're in a class A, B, or C where you can go between living quarters and cab without going outside. There's maybe more risk in a towable or TC, but I have no idea of how much more.
I've stayed in a lot of truck stops, rest areas, and a few WM's, but I'm a solo traveler in a 19 foot C that fits in the car spaces. I actually prefer truck stops. WM's are quieter on the average, but there's always the lot sweeper or a jasax with no mufflers at 2 am. Trucks stops tend to be at a continuous low roar, which I can sleep thru. But I do carry throw-away foam earplugs in case they're needed. I keep my wandering around outside to a minimum day or night, and look around before opening the door.
Jim, "Mo' coffee!"