Dunno exactly how it's set up in the 1980s Nighthawks, but the 91-03 models have a passive crankcase ventilation system that disposes of the byproducts of the engine's heating and cooling cycles like this:
Those cycles produce minute amounts of water condensation mixed with oil which drains through a tube to the bottom of the airbox. A passive separator in the airbox allows whatever vapor is in the mix to be routed to the carbs where it's mixed with fresh fuel and burned in the engine. The residual liquid ( thin, brownish and watery) in the separator then drains into a clear tube in the bottom of the airbox where it collects until you empty it during routine maintenance. The tube is routed to the ground in front of the rear fender and should have a plastic plug in the end (unless it has been tossed or lost by a previous owner). Emptying that tube periodically is important. Otherwise the liquid can back up in the tube over time, overflow into the airbox and cause a confusing combination of engine problems (rough running, etc.) So, though a film of oily residue in the air box is normal, a build up of anything more would indicate the disposal tube should be emptied. Like, right now, if not sooner! y, May 19, 2018 at 9:27:26 PM UTC-4, Raymond Gomez wrote: > Thank you all for answering my question about the cylinder side > thingamabobs. Lol I can easily acquire them from the Honda Dealer up here > in NW OHIO. > I have another issue though. I am in the process of doing some well over > due maintenance on my nh,and during the course of my work,I opened the air > box up in preparation to replace the air element,and I once again found > about an ounce of oil in the bottom of the air box. This is the second time > I have encountered this phenomenon. The engine was leaking oil from the > valve cover gasket that I am in the process of changing,but the engine > never leaked enough oil to cause this,and while I was riding it I kept the > top of the engine clean. > My understanding is that there are two lines that go from the air box to > the crankcase,is it possible that a loss of vacuum in the carbs (the carbs > have never been cleaned that I'm aware of before I bought it)could be > causing it? The bike has two nickel sized holes in the mufflers and the > engine has a terrible hesitation going on at low power,once you give it gas > she takes off,but at idle or low power,the bike seems like it is always on > the verge of stalling out. I don't want to do any guessing,but I'm > wondering if the old girl might have bad rings,or something else going on. > Can you guys give me a clue what's going on? The engine has 42,000 on it > and has never been overhauled. Thanks > Ray Gomez > Grand Rapids,Ohio > Ps,I'm getting ready to tear carbs off for cleaning,there is no oil in the > barrels/intakes and she's running very rich as well. -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/nighthawk_lovers. For more options, visit https://groups.google.com/d/optout.
