Hi, My name is John Bucknall from Australia. I have a 1998 Sprint which i have been restoring, It had been sitting i a barn for 11yrs. I have had it running fine then all of a sudden it developed a flooding problem, It has started to blow back up from the breather hose from the crank case into the airbox, this is a big leak. I can also smell fuel in the oil. Could anyone please give me some clue as to why.I have spent a lot of time and money on this bike and haven't had it on the road as yet. Needing Help. Cheer's. John.
Hi, The oil level was correct prior to flooding, it's over full now, i can smell fuel on the dipstick. Because i couldn't see where the leak was coming from i removed the airbox so i could see where the leak was, it was spurting out of the vacum/vent hose from the crankcase and goes into the bottom of the air box, before this it was coming out the back of the airbox which was why i removed the airbox so i could see. Thank you for replying.
Hi and welcome. Firstly is the fuel cap in the vacuum position , not the prime position. If I recall correctly turned fully anticlockwise is prime, middle position is to be left on as it is vacuum operated as is reserve which is with the tap turned fully clockwise. It could also be the float needles and/or o rings. Sprint mfg do sets of both. Also check float heights are in spec. You are best to post these questions in the relevant section as not all of us look at newbies posts.
So that confirms that fuel is somehow draining into the sump and mixing with the oil and the crankcase breather is doing it's job by ejecting the overfill to relieve the pressure. It looks like you need to check the carbs as others have suggested.