EV puking oil out the breather hose

[Mr Revhead]

Just completed an 1800km road trip
Yesterday on the last 600km leg, near the end, I stopped for a break. And a good 200ml of oil spat itself all over the ground! Had a look and it all came from the hose that drains from the bottom of the air box.

What the heck causes that? I've had a bit from there before, but never this much! Speeds and revs weren't excessive, cruising at 100-110 kmh and about 4k RPM in  4th for the most part, with higher RPM when over taking.
I'd have though the breather system would allow oil to drain back into the sump, but it seems not. parts diagram doesn't show any valves or one way check valves that might cause it.
Oil wasn't overfilled, it's now down a little.

[pete roper]

Check the ball valve in the breather hose and flush the frame. Chances are it's just gummed up with rusty mank.

If not that? Blown head gasket between combustion chamber and pushrod tunnel.

Beyond that things get serious.

I doubt they will be.

[Mr Revhead]

Ah! One has a ball valve in it? That'll be it then!

[jacksonracingcomau]

mayo thread coming
hose from head to frame is full of it

[Mr Revhead]

No mayo, it's nice clean oil, left a hell of a puddle! 

[kfz]

This comes up so often here in the UK where it (used to be) damp and cold, especially for all year round riders that the breather was completely gummed up I ended up getting the pad out and filming a quick video of the mods I made to solve it. Probably over the top if you live in a warmer/dryer climate.

Kev

https://www.youtube.com/watch?v=g1k6tz_Eq_0

[pete roper]

Yup. What happens is the return pipes clog and block, (May also be the spigots in the frame.) then the frame fills up and the oil pours out the breather hose which goes to the airbox and thence to the outside world.

It may also be that the ball valve has stuck open and there is far more particulate expansion.

Either way it needs a new valve by now and a good clean out of the whole breather system. The poor thing is twenty years old! Give it a birthday present!

Pete

[Mr Revhead]

The poor thing is twenty years old! Give it a birthday present!

Pete

  16 years! It's seen half the country in two trips since end of october! Thought I was spoiling it!

[antmanbee]

How do you go about cleaning inside the frame? Besides the need for having a good working breather system I read on a post
 somewhere that a V11 frame was bead blasted and some remnants of that from inside the frame made its way into the sump
 and damaged the bottom end. So a frame flush might be a good thing under some circumstances. 

[John A]

If the ball valve closes off oil will be pushed out the breather drain to the level of the return tube in the sump.  At road speed it'll do it in a flash.   There is a design change in the ball valve.  The early one has a round end that the ball can seat in,  closing it off. The new one has a square exit that the ball cannot close off.

[John A]

How do you go about cleaning inside the frame? Besides the need for having a good working breather system I read on a post
 somewhere that a V11 frame was bead blasted and some remnants of that from inside the frame made its way into the sump
 and damaged the bottom end. So a frame flush might be a good thing under some circumstances.

To flush, separate the hoses from the engine and run mineral spirits through it, with a syphon run off an air compressor or a parts washer pump.

[Mr Revhead]

So.... Where is this ball check valve supposed to be?? Nothing like that on mine... 2003 EV.
To hose from each head to frame. Small diameter from frame tube to air box then just below that on the frame tube is a large diameter hose running to the too of the timing chest. No check valves on any of those. All the frame connections are just welded on spigots. Spigot on timing chest is just a hollow tube.

[pete roper]

So.... Where is this ball check valve supposed to be?? Nothing like that on mine... 2003 EV.
To hose from each head to frame. Small diameter from frame tube to air box then just below that on the frame tube is a large diameter hose running to the too of the timing chest. No check valves on any of those. All the frame connections are just welded on spigots. Spigot on timing chest is just a hollow tube.

Sorry, 2003 moved the breather to the timing chest, my bad. OK, it's probably the returns to the head that are clogged. That or blown gasket to pushrod tube.

Pete

[Mr Revhead]

Haha ok. Yeah they were a bit clogged, all clean now.
Guess I have to ride it again to check

[DorsetBlue]

Haha ok. Yeah they were a bit clogged, all clean now.
Guess I have to ride it again to check

Just a little warning, my V50 Mk2 did this once while I was on the way home from the British GP at Donington (ah, those were the days).  Turned out to be worn piston rings.....however the cause of the worn piston rings was that the numpty previous owner had done a whole engine strip down due to a Clutch failure and had put the thrust washers on the wrong way around (hardened side against crankshaft instead of the crankcase). Result?  The washer ate it's way into the crank until there was so much play, the crank was moving about 5-10mm forward and back.  It kept running even until the amount of play got so bad, the pistons wouldn't slide in the cylinders.  Loved that bike but that was the end of it alas. 

[jacksonracingcomau]

Haha ok. Yeah they were a bit clogged, all clean now.
Guess I have to ride it again to check

only a bit ?
usual is complete