Just picked up a loncin 250 atv for next to nothing. I got it home and rebuilt the wiring Harness enough to get it to run and it runs great but it puked up watery oil all over the place. So now I need help on where to look for the water leak into the motor. I was told by the previous owner that it had a bad head gasket and has sat for months but idk if that would drain the entire radiator into the crankcase. I see some damage to the water pump impaler from an attempt at removal but no idea on how to remove it or of that's even the issue since it still functions fine. Any ideas where to start?

 

On any engine I have come across, a drain hole allows any water that gets past the pump gland to drain out to atmosphere rather than getting into the engine. So if it has a drain hole, the most likely place for a water in oil leak is the head gasket. If it has a "wet liner" the base of the cylinder liner is another common place for a leak.

 

ok sounds good it seems like ill have to order a gasket and rings anyway since yesterday i had it running for about 5 minutes and the blow by is horrible. it can be felt about 5 feet away lol and if i plug the vent tube it starts to push all the oil out

 

Head gasket was completely blown now im trying to find somewhere in the US that has one but can't seem to. Any place you guys know of that have a 70mm(69.85) head gasket? Also need to get some pictures of the frame to get help identifying it so I can get some plastics and brake hardware since it has neither that fit, it came with a Honda rear and ink wht the tank covers is from but neither really fit it. Also has no functioning brakes and the clutch seems stuck as i cant get it disengaged.

 

Maybe it wasn't such a bargain after all. Loncin are a big name in "Honda clone" engines. They make many of the GX160 etc, copies which power Generators, Tillers and the like, so I would guess that engine will be a copy of a Honda 250. Can be any age, and scooter or motorcycle. There are Chinese parts specialists, but they would need to know what model you have. The engine will probably be stamped with a number containing this info. Or you can Google Loncin 250 engine and see what comes up. This will help with plastics too, though are you sure it is a Loncin? As other Chinese makers used Loncin engines, and if the only identification is the name on the engine, the frame could be Buyang or other Chinese maker. Clutches are quite tricky, as the Chinese makers don't always copy Honda, and variable belt drive, forward reverse only, manual gears with the gear pedal acting as clutch pedal too, are all alternatives to the clutch lever on handlebars, that a 250 Honda motorcycle would have had.

 

Well I traded it for a car with a blown mother that the junkyard offered me $70 for so I'm at no real loss. As for the frame I haven't seen any marks on yet and I'll get pictures up when I'm on my computer since I can't seem to upload from my phone. I know it has a rear hydraulic caliper and the front is cable but I have no master cylinders for either so that I'd need the frame model for also. I go in depth the head gaskets online from China but it'll be almost January before I get them from there lol
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Well pictures were posted a few days ago but still awaiting administration approval but from what I've gathered so far with the help of a buddy with alot of atv parts is that it seems the frame is from a Honda sportrax as his 250ex looks like a bolt for bolt match. I just can't seem to find a Vin or anything since this thing has multiple layers of spray paint. So hopefully all the Honda brake parts ive ordered match up which just leaves me to wait for the headgasket to arrive and unstuck the clutch which does seem to fully actuate just not disengage in the case but could be from all the water that was inside the crankcase

 

Honda VIN numbers are always across the front frame member that the bull bar mounts onto, maybe the maker copied this too