One way Valve on Crankcase Breather?

[jonny500]

i totaly agree with bdi's last post. i have alot of experience with 2 stroke mx bikes and by the sound of it so dose bdi

[demographic]

On my carb breathers I have connected the outlet pipe to a T piece, one part of the T faces down to the bottom of the bike and the other goes up into the airbox.

That way if the bikes in water the breather can't suck water up as the top pipe doesn't allow it to get any vacuum.

I assume it wouldn't be too hard to do the same with the transmission as well if needed.

There's a picture showing the setup that I copied here...
http://books.google.co.uk/books?id=kuYFuUqzNBMC&pg=PA100&lpg=PA100&dq=carb+T+vent&source=bl&ots=wK5lV5DLii&sig=luUXDuL5Md1hNONFxcPULZ-Af3s&hl=en&ei=ugklTOTIDMaSOOK_jLkC&sa=X&oi=book_result&ct=result&resnum=8&ved=0CDQQ6AEwBzgK#v=onepage&q=carb%20T%20vent&f=false

[Narkotik666]

uurugh....okay, i better get some images of what i'm talking about.
i think i might be giving the wrong info. (i hope)

or that i am giving the right info (then i'm worried)

Doom prophecy.

but, surely, there will be so "sign" that the motor is going to pop....like sloppy throttle response, low power,etc etc etc.....if the seal are cooked and the motor is going to EXPLODE.

trust me.....the thing is as responsive and snappy and snarley as a squirrel on speed. (at the moment).
but i will post pics of what i'm talking about. and a full description of symptoms. before i loose a motor...cause i am taking the bike too "hell" this weekend......

[Narkotik666]

okay, attached pictures. (hopefully)

where the new WHITE hose comes from, is that the crankcase breather?
it used to be a thick black hose that pointed down, and some oil and smoke would drip out of it (little bit, after and during some hard riding...it doesn't leak though.....) (is that normal?)
with the hose pointing down setup....i used to get water in my oil, from rivers and obviously trying to kickstart it in rivers with the end of the thick black hose submerged.
The second setup i tried, was with the thick black hose pointing UP....and with that...i had BEAUTIFUL GOLD OIL, after riding rivers and mud and puddles....so, it didn't suck in any water...but i had oil all over my pants and engine....as you can see.

so, what i did, is attach a longer white hose (it had the one way valve, but i removed it)....all i did was loop it up and to the back of the mounting it higher over the chain(the end pointing down)...so in theory it would act as a chainluber (hahaha, i know its silly, but, why not).

so the question is.....IS THE PART WHERE THE WHITE HOSE GOES IN, the Crankcase Breather....and what should be the NORMAL things i should see...
at the moment....it blows a bit of smoke...and drips a bit of oil, at speed. and i guess it sucks up water when kickstarting with the end submerged. (its NOT the water pump seals....i have golden oil when it pointed UP and away from water)

[Hillclimb#42]

That must be a newer 250 than mine. My bike does not have that powervalve vent. I have a Yz125 that has that powervalve breather. The crankcase breather hose is the vent hose that comes off of the top of the transmission. Usually the carb lines are clear (stained brown) and the cranckcase hose is smaller and black. The hose you are pointing out there, comes from the powervalve. My 125 that has the same breather hose, drips oil and puffs a little smoke, too, but I cannot tell you the purpose. I do know the factory has it mounted to the frame pointing down and mine does not suck water on the yz125. Its definately not crank seals leaking, but could be a seal or gasket in the powervalve assembly.

[Narkotik666]

Well, thank goodness.....its the POWERVALVE BREATHER!!!!!
that coughs oil and sputters some smoke......

THANK YOU THANK YOU THANK YOU...

sorry guys for the missinformation....i was talking about the Powervalve Vent not the crankcase breather....
i feel much better....

sheeew!!!!

[bigbellybob]

Something has to come out of the gearbox to actuate the PV. That means that the gearbox is somewhat open to the PV. The exhaust creates a lot of vacuum so i can see it sucking in water. If the current routing of the hose is working for you IMO you will be good.

[BDI]

When crap starts coming out of that vent I'm pretty sure that means it time to clean the power valve.

[The Flyin Hawaiian]

You will get abit of dripping and smoke out of the PV vent tube, its normal. My 04 and my girls 07 do it. You may get a little bit of condensation also. My old 01 and 02 YZ250s also dripped from the PV vent.

[Narkotik666]

This is GREAT NEWS...

expect some dripping and smoking....CHECK!

CAN suck in water....CHECK!

New routing should be fine....CHECK!

I am sure this solved like 5 different issues in one GO!
Thanks so MUCH!

[The Flyin Hawaiian]

I have my vents routed down like the factory had them, otherwise it wont vent/drain properly. That black goo will end up collecting in the cover.

[Narkotik666]

yeah, i thought that there wont be enough pressure to blow the goo out...when i had the hose pointed straight UP.....but low and behold....i had a dirty boot/ dirty pant / dirty radiator and a dirty motor....so its blows with some force, I am sure...that i would get it to go OVER the motor, and out the back.....which i point down, so the last bit of the "draining" action....gravity could help out.

Attached is a image / diagram of the extension and the tip where it "spits"....right over the chain.

i attached the "stock" hose with the L bend to the frame.....the L pointing Back....and added the white hose from the POWERVALVE to the top of the Stock hose.

and whenever i end the ride....i close the petcock....and burn the last bit of fuel in the carb....so maybe...that would also blow out the last bit of goo in the pipe....or i can just remove the white hose from the powervalve it self....and blow it clean like that?

[jonny500]

sorry i have been away for a few days. right as the other guys say it is your pv vent. as it is blowing and sucking i would say that some of the seals are not working. i can not think of any damage that would result from runing it in this state as long as the water is kept out (PLEASE CORRECT ME, ANYONE). i would say the best thing to do is wait until your next top end over haul and replace anything then. i have included a diagram of a 99 250 barrel not the same as yours but you can get an idea of what needs to be done.
regards john

[Narkotik666]

Cool thing is....i have a 2 year Factory Warranty on my bike.....and i plan to rebuild it twice before it runs out
i mean....MAKE them rebuild it....then, i'll make sure EVERYTHINGS covered.

and i know, i AM dubious about dealer/stealer warranties.....but, i have to say, these guys are pretty good, they even replace the fork seals when they start weeping.....only place in SA that has a warranty like that....so, i am sure they will cover everything needed.....

paid top dollar for it.....and well, after the "HUSABERG INCIDENT" i will never ever buy a 2nd hand bike without a warranty. (AND NEEEEEEEVER EVER buy a 4Stroke...okay maybe a KLX450)

thanks for the heads up Jonny.....i will make sure to be critical when they do it.