Cummins-Onan RV QD-3200 help

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When I got it home I noticed it smoked blue under load, found oil to be over filled by 7 oz. (oil was just changed at Onan/Cummins authorized facility by PO) Sucked out the excess and now no smoke at all even under heavy load. However the crankcase breather leaked quite a bit of oil and made a mess, both from the little hole in the valve and at the connection where I drew the arrow, not sure if this happened because oil was over full or parts are worn and it's been leaking for a while. Maybe oil accumulation is normal right there and I should just keep it cleaned up every so often? I never opened the cover until we had ran it for a couple hours. There is a split sleeve over the breather line that I don't see on the exploded view, unless that is supposed to be a complete piece of hose and not split like that, lots of oil in that area. Looking on ebay that breather assembly is over $100, also fuel filters are $47 at the cheapest place I could find. What is so special about that filter and where is a good place to buy parts for Onan without getting raped too much?The unit is 9 years old and has 180 hours. Starts immediately and runs strong, barely hiccups when AC starts up even with 1,200 watt load already running.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:I pulled the breather assembly apart and the part#3 in the attached diagram that is called the Adapter is the hose that's split. It looks like it was intended to be split but the diagram appears to show a complete piece of hose not a split piece. The valve is hard plastic and the skinny tube that connects to it is very loose and does not fit tightly into the valve, this is where a lot of oil has come from. Is this fit supposed to be loose for a reason, maybe to protect against positive pressure in the crank case? I am thinking about replacing the split piece with a solid piece to make it more of a liquid tight connection.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:I don't have a unit here to compare to but if I had to guess I'd say that piece of hose just split and allowing oil mist to make the mess. It should be replaced with an oil resistant product such as PCV hose.As for the filter(s), I just cross the number(s) to my preferred brand such as WIX, NAPA, FRAM, etc.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:Thanks DuaneB, I was hoping you'd stop by. The manual also recommends exercise 2 hours per month at 50% or more load which seems like a lot but what do I know? If that had been done since new it would now have 240 hours just in exercise hours and it only has 180 hours total.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:So the piece of hose that is split was obviously put there as a rig. The hose that is needed connects to a 1/4" OD line on one side and a 1/2" OD line on the other side (sizes within 1/32"). That hose must have broken, there is still a tiny chunk of it on the 1/4" line. Someone just shoved the 1/4" line into the 1/2" fitting on the valve, a very loose fit, and slit a piece of hose and slipped it over the whole thing. It has been making a mess of the motor compartment. The hose I need is only about 2" long to connect both sizes, I may look in the Dorman "Help" product line or maybe make something by bushing up the smaller hose to fit inside the bigger one. Onan/Cummins does not list the part# for that hose, only the entire breather kit for over $100.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:I 'd throw that breather assembly in the trash and get a catch can. Diesel blow by just gunks up the intake and you can get soot issues. Cheaper too, although you will have to empty it occasionally.You can mount a remote fuel filter, a Racor 500 element is about $14, much bigger than you need so it will not have to be changed for ages. Of course, the remote housing is more unless you can find a used one on eBay. You need to load up a diesel or the cylinders can glaze. Try and warm it up with a moderate load and try and not let it idle too long. I don't mean high rpm, but definitely a load. Is it a genset or a welder? If a genset, try and plug in a heater or something that loads it. If it's a welder it should be loaded every time you use it so no worries.Do not believe everything that you think.
Reply:It's an onboard RV genny. They recommend loading ot to at least 50% while exercising which I did using the AC unit and a 1,000 watt resistive heater. I am going to put together a 1,500 watt load for future exercising,  probably a shop heater. I have 3-1,000 watt 120 volt shop heaters, I could just run two of those.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:I was able to make a new hose by heating up a piece of 3/8" ID with a heat gun and shoving a piece of 3/16" ID into one end, then fitted the two parts together. Worked very well. I never thought about a catch can on a generator, I got one on my Powerstroke and presently trying to figure how to do one for my Sprinter. On my Powerstroke I kept it a closed system, routed the CC vent into the can and back out to the intake. The can catches the oil and the air returning to the intake is clean and dry.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.