yamaha pumiping oil

[Prospector]

ok, my mate has 3 YFZ there all bombed. he has an 05 and 2 06's. all 3 bikes are pumping heaps of oil out of the crank case breather? they have chnaged barrells, pistons, heads, they ahve even pulled the case apart on one of them and nothing has worked. so if this has or is happening to anyone else or you know whats wrong please let me know! thanks

Chris.

[daddio]

It sounds like they are putting too much oil in the bike to begin with. A bone dry motor takes 2 quarts. 1/2 of a quart in the motor and 1-1/2 quarts in the tank. Check the oil level after it has ran a bit and the motor is warm. Run the oil level on the lower 1/2 of the dip stick. I've run accross this issue several times.

[tuefelhunden]

This will happen if you let it sit at idle. Especially if it is hot. It won't happen if you are running it under normal racing conditions but for some reason it does it when the engine gets hot. It has never happened to me when I have sat on the line b4 a moto but if I go back to the pits afterwards and let it run a while it pumps it in like crazy.:mad: It has happened to many others I know as well. Just try to keep from letting it sit and idle when Its hot and you should be fine.

[tido450]

this should not happen at all if u have the propper amt of oil in it. and if u have not removed the black breather box. the only people ive ever seen have this problem in 2 years are people with too much oil
u cant check the oil level after its been sitting. start it and let it run for a min then check. what happens is the oil from the tank goes into the motor when it isnt runn creating a false low reading. it pretty much sounds like they think they got it all figured out but are forgetting about minor details

[Prospector]

yeah they thought that as well, so my mate only filled it half way, it was still pumpin oil when the reading was off the dip stick! soo the only other thing they can think of is to make the crank case breather bigger! i will tell him what you guys have said but yeah thanks!

[daddio]

Does it "pump oil" right after you stand it on the grab bar to clean it?

[PurePerformance]

It sounds like your putting too much oil into the engine, but again, if you look in that black box where the crankcase breather connects to, it actually provides as an overflow. If it only sputters oil then it is normal as crankcase pressure and position of the quad will cause some oil to come out, but if it is constantly blowing out of the breather, you might be putting too much oil. When I do my oil changes and replacing the oil filter, I usually use 2 full quarts into the oil tank, which basically fills it up and run it. After a couple of minutes, the dipstick reads where it should be.;)

[markeg192]

Could be compression from the cylinder blowing into thw crankcase . My sons EX just did this and turned out the headgasket was leaking . Pull the dipstick and see if it blows.

[Prospector]

he is deffenantly not over filling it, it pumps out a **** load of oil, every time he rides it more and more oil! they thought it could have been the head gasket but they ahve changed that, the barrell, head, piston and still it does it! it doesnt pump oil while idling only when your riding it ot racing.

[daddio]

Do a "leak down" test, and see if you have a problem with the valves or cyl.