What would cause oil to come out my throttle body?

[jtascone]

Hello all. 08 Nomad 1600 with 27,000 miles on it. Bike is running great, but today while riding on a very cold day here in NY, I noticed that the air filter inside my Hypercharger is soaked on the bottom half with oil (not air K&N oil, motor oil). This has never happened before. It has to be coming out through the throttle body. Anybody know what would cause this?

[Peg]

Wouldn't it have to be from the crankcase breather? It'll depend on how that breather line was dealt with when the hypercharger was installed. Either it's plumbed into the intake system to be burned off, or it goes to a standalone filter.

[jtascone]

I'm not sure. The Hypercharger was on the bike when I bought it. I've washed and re-oiled the filter once in that time (about 5000 miles ago after putting about 6000 miles on it), and there was zero oil in the throttle body then. I've put the last 11,000 miles on it and this is the first time I've ever had this issue. I thought maybe somehow I might have accidentally overfilled the oil, but I just checked the oil level and it's just below half way in the sight window. So it's not from that.

[andyvh1959]

Slight oil mist from the crankcase is normal. Hot oil mist from the crankcase can condense into the air filter housing. That is normal, and then usually is a drain line from the airbox back to the intake or crankcase so the oil mist doesn't condense into a pool of oil. For oil to get into the throttle body something, some force is "pushing" it up there, or it cannot drain back into the crankcase. I would just check out the entire crankcase ventilation system to back sure that something (a critter?) has caused a blockage.

[jtascone]

Good advice. I will look up everything that has to do with the crankcase ventilation and check them for obstructions. Hoping it's something that simple. I would think with only 27,000 miles on the clock that it shouldn't be anything serious engine wise (pistons/rings/valves). I ride a lot, but I don't ride hard or aggressive. Oil has been changed every 3000 miles and bike seems to be running fine. Praying it's something that simple.

[andyvh1959]

Ha, maybe some critter decided to stash something on your bike. Had a coworker decades ago asked me to check out why his late 70's vintage Suzuki GS750 would start and idle fine, but would die as soon as the throttle was touched. He was all concerned about a serious engine issue. I sensed something was keeping the engine from breathing.

Opened the airbox, where the air filter is underneath the seat. Then I asked him d o you always store dog food in the airbox? It was stashed full to the top with dog food nuggets. We emptied the airbox, cleaned out the crumbs, bike ran fine. Some enterprising little mouse figured the airbox was a great location for a foo stash.