Why is there oil in my intake pipe?

[Madjackal 0]

I have just been fitting my new big bore TB (courtesy of alpina) and while doing so noticed some oil in the intake pipe. Is this normal, or if not is it something to worry about?

[bighands 0]

I had this, thought it was a blocked breather pipe from the bottom end blowing oil up in to the intake, replaced pipe, and it didnt fix it, that should be your fist port of call, a small amount is 'normal' i think

But, with me it seems it was the head gasket blowing for the second time in 8 months ::(

Hope its a small amount, or just a blocked breather pipe mate!! (im taking it you have a valver?!)

[Madjackal 0]

no mines a VR.

[bighands 0]

ah well then it could still be something along them lines i would of thought, but im sure someone will correct me as i havent fooking clue about VR's!!

[sciroccotune 0]

some oil is normal, if the vr is like the 16v then there is a breather pipe that puts fumes back into the intake, which over time causes an oily build up.

[Kevin Bacon 5]

It's normal. Most VRs do it as do most cars with breathers! It should only be a light oiling, if there's gallons of the stuff in there then you have problems!

 

I just run a long hose out of the rocker cover straight down to the steering rack :-)

[Madjackal 0]

Not much oil in there.

 

So what is the function of the breather hose? and same question with regards to the two that come off the TB?

[davidwort 0]

It's normal. Most VRs do it as do most cars with breathers! It should only be a light oiling, if there's gallons of the stuff in there then you have problems!

 

I just run a long hose out of the rocker cover straight down to the steering rack :-)

 

tut, tut, :) hope you fix that for the MOT, don't think it's legal to vent to the air unless it's built like that.

[Kevin Bacon 5]

LOL, yeah I do reconnect it for the MOT :-)

 

Alan, the breather is there to make sure the engine burns it's own waste gases that blow past the rings. As David said above, it's a legal requirement.

 

Think of it as running a tube from your arse to your mouth and every time you fart, you breathe it in.... :-)

[Madjackal 0]

Nice! :gag:

[bcstudent 0]

the breather is there to make sure the engine burns it's own waste gases that blow past the rings.

Surely if the oil had gotten past the piston rings then it'd already be in the combustion chamber ready for burning. It wouldn't need to be piped there.

 

The breather system is to equalise pressure and transport the oil mist from the crankcase to the engine intake. The oil mist is created as the downward motion of the pistons increases the pressure in the crankcase and the moving air takes some oil with it. If the breather pipes become blocked then the pressurised oil still has to go somewhere, i.e. past gaskets, seals and piston rings. If you overfill the engine with oil you'll find that it gets messy!