wr400 air bubbles in motor oil?
Posted December 06, 2011 - 12:19 PM
Posted December 06, 2011 - 03:46 PM
Posted December 07, 2011 - 07:54 AM
Posted December 07, 2011 - 09:03 AM
Posted December 07, 2011 - 09:17 AM
Posted December 07, 2011 - 10:37 AM
Posted December 07, 2011 - 10:45 AM
Are there any visible oil leaks anywhere? If so you might start there.
There could also be a tiny leak on a hose or gasket somewhere (possibly an area with vacuum) that is letting air in but no oil can get out.
Make sure oil level is correct. If it's too low it will cause the oil pump to suck air and mix with whatever amount of oil it is pumping. If oil level is correct after the bike sets for a while perhaps an oil return route is blocked not allowing oil to return back to the oil pan quick enough. This would cause the pump to pump the oil out of the resevoir faster than it returns causing the symptom of low oil level.
Cheap oil will foam more because of poor anti-foaming additives.
Check very carefully and make sure there is absoulutely no sign of oil in the coolant. Does the bike overheat?
Here is something else I read:
'Bubbles' in the oil are not good. Usually, they're not air bubbles, but water droplets. When you see them, it's a sign that your oil is contaminated with water and needs to be changed. A more serious problem is how the bubbles got there. Quite likely, there's a leak between the system that circulates oil (to lubricate moving engine parts) and the system that circulates coolant- the water 'jacket'. Could be something relatively simple, like a blown head gasket, or something really ugly- like a cracked head.