engine breathers

[jetfire1383]

having problems with my 600n, the breathers were all over the place.

can someone please tell me where the rocker breather and the crank breather are suppost to be, i conected them both to the air box but after a few miles it started sending oil into the air box from the rockercover breather, and when i disconected it from the air box it hammered oil out all over my bike trousers

cheers dai

[CD]

If the bike is doing short journeys the main breather pipe can get gunked with oil mayo sludge.

The crankcase breather should be as clean inside and run ans directly as possible. People like amorti have had success with garden hose and the longest curves possible to get a good airflow. The cam cover hose can just go straight to the air box. I drilled a hole slightly smaller than the hose outside diameter (something 6mm but dont assume that's accurate) and just pushed in in.

As the engine is blowing out oil, check the sump level is correct and also look for leaks on the oil cooler. They crack on the hex shaped boss under the oil pipe banjos.

Also disconnect the clutch cable and check the operating lever on the clutch cover has no slack in the bearing. If its worn the seal will fail and water gets into the engine. It causes mayo when its boils off into the breather system.

[jetfire1383]

thanks for the help. but i managed to fix it today, it should have t piece in the airbox and the crank breather goes in one side and the other side takes the cam cover breather, the t bit allows the oil coming out of the cam cover to flow back in to the crank case and the gas to flow into the airbox,

i did the clutch rattle fix the other day and replaced the bearing and washer and the seal on the clutch lever in the case.

many thanks for the advice
dai

[amorti]

You're as well to remove the breather hose from the rocker cover.

The big one from the crankcase is well baffled so oil can't get up it, put it's also pinched tight under the tank (you will see witness marks) and tends to kink and get blocked. Then the breathing has to be done from the top hose, which isn't baffled, and oil gets into the airbox as you've seen.

Use a bit of garden hose on the main breather (it's braided and doesn't kink easy, also cheap/free) and remove and block off the top one. It's meant to help against carb icing but it doesn't do much. If you get carb icing, put 150ml per tank of fuel of IPA into the tank with each fill up (half a panda pop bottle)

[CD]

The clutch rattle is not the same issue as the clutch operating lever seals. Check the clutch operating shaft bearings are not slack because water off the back wheel gets thrown right into that area.