Question About a 225 Lincoln Onan

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A friend of mine gave me a 225 lincoln with an Onan engine . It runs way to lean and stalls out, but the carburetor will not adjust, the needles move in and out but it won't respond. I think it needs a carburetor kit. So what am I doing wrong ?   Thanks for any input about this machine.
Reply:You're not doing much wrong if someone gives you a free (Lincoln) welder.
Reply:Welder Dave you got that right! If it's been sitting unused, Yep gonna have to rebuild the carbs.Thermal Arc 210 - Tweco 211I - Cutmaster 52
Reply:Replace the spark plugs first.Autolite 437 or Champion H12.You need a hotter plug for the gas we get now.Use fresh gas.Carb  can stand a good cleaning.A bowl gasket is all you need.Onan parts are made of gold.My Onan has an auto choke so make sure its working right,might be opening too soon.Give the engine time to warm up.
Reply:Sounds to me like you've got a vacuum leak between the carburetor and the engine. A tiny amount of gas dribbled around the gasket connections of the manifold might find it. You will know, when the engine changes sound and speed. The Onan Performer 16 hp had manifolds made from 2 pieces, a top half and a bottom half. Check this seam for possible leaks too. If you don't find a leak, a carb re-build would be my next option.CharleyMiller MM252Miller Bobcat 225NTMiller DialArc HF / DIY Cooler2 Victor O/A TorchsetsMilwaukee 8" Metal SawMilwaukee Dry Cut "Chop" Saw 5 Ton Wallace Gantry Various Grinders, Benders, etc.
Reply:Spray around it with carb cleaner or WD 40 if rpm picks up you have a leak.  John
Reply:Don't be afraid to put a complete rebuild kit in the carb? Sometimes it can do wonders on an old motor. What make of carb is on it?JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:Thanks for the replies. I haven't thought about a vacuum leak around the carb. , and I did not know that the manifold was a two piece part. I will test for a vacuum leak next. The carburetor is made by marvell scnieber. I can get it to run but it dies down under a load. It is a fickle engine, I'am more accustomed to diesels. Still leaning towards a carburetor kit. Thanks again
Reply:Have you confirmed it's running on both cylinders?  Those Onans will run on one but won't take a load.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:My old blue star 2e with wallbro carb was backfiring when the motor would idle down. I put a rebuild kit in the carb ($20) and adjusted my float height to spec and the backfiring was gone. The motor idles down nice and smooth now.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:My buddy work as a small engine guy at a repair shop. It seemed that the vast majority of problems were carb related and due to old gas. Granted a lot of these machines were things that sat a lot, generators, lawn mowers etc. But with the ethanol in the gas it really pulls water in from the air and dissolves it in the gas. (especially in the very dry Pacific Northwest) a cleaning or  a rebuild could not hurt, especially if the unit sat for a whileEPS Conduit  CouplerGraviton emitterPhase coil resonatorTweeco Fabricator 181older Century buzz boxLincoln 110 box
Reply:Originally Posted by duaneb55Have you confirmed it's running on both cylinders?  Those Onans will run on one but won't take a load.