As per the title, I found quite a bit of oil in the bottom forward part of the air-box. Not the first time and I remember other people mentioning it.

What causes it and do I have a blocked drain hose?

 

is it a K&N air filter if so it was over oiled - if not shyte I have no idea ..........maybe the result of a bad pint !

 

i've heard that this is a result of too much oil. be sure to check your levels so you don't overfill it.

 

of course Steve it could just be the breather hose form the valve cover doing it now that
I think of it and that's perfectly normal - just give her a good clean out I think there's
a puke hose out the bottom of it that may be blocked - I know my KLR has this can't
remember if the Hurricane does

edit

yeah it does and it has a plug on the end

items 22 & 25 on this page

http://www.partzilla.com/parts/searc...NER/parts.html

 

Normal OEM air filter.

I think maybe the drain tube is blocked Mark, I'll have a poke about with an old wire coat hanger.

Thanks for the replies.

 

I have an old Jeep. When I found oil in the air cleaner, it was a result of the PCV (Positive Crankcase Valve) not working. The PCV allows bypass gasses from the engine to be reburned. When it clogs, there's too much pressure in the engine pushing crankcase oil instead of gasses.

With a drain tube on our airboxes, Honda must have known that some oil would be sucked up into the airbox. Just take the cap off and let the oil drain. But I think you should check the air vent filter on the right side of the frame. Take the top off the little filter and clean the foam element in soapy water. Dry it and reassemble.

 

Do our bikes have a PCV?

You mean the one to the right of the coils?

 

hmmmm but that one connects to the diaphragm side of the carbs - good maintenance
but not sure how it'd apply here

Not aware of any PCV valves in a our Hurricanes just the breather hose from the valve
cover to the airbox - which is why the drain tube and cap is attached to drain it
occasionally

 

Hawk,
the little filter to the R/H side of the coils is to vent the top of the carbs, nothing more than that. You'd have to stick a cork in the end of the tube for that to make any difference to performance.

Anyway, back to the oil.
On my old CBR (gawd bless her) when I fist had it the breather tube from the rocker cover to the air filter used to regularly fill up with what I can only describe as cow snot. Gooey sludge, almost like it had been filled with grease.
This continued until I refurbished the head. After that it never happened again. The tube and air box remained clean.
My bet is that it was due to the valve oil seals having gone past their sell by date.
After the head job she used no oil at all. Before it was going through around 0.5 L per 1500 miles.
She never used coolant though although I did suspect that there was a tiny bit getting into the exhaust at times.
Your mileage is probably about right for the valve seals to become a suspect. There will be some pressure leakage through bad seals too and it is probably this which forces the cow snot mixture back into the air box, the path of least resistance.
There's no PCV as such, just the recirculation of positive crankcase pressure back into the air box.
There is a drain pipe from the air box which emerges below the R/H side kick panel. it has a plastic plug in it which you need to twist out of the pipe after releasing the cir clip round the rubber tube. Any liquid in the air box drains out and you pop the plug back in again.


If you want any advice on the head refurb give me a bell or I can post up a bit of a mudus operandi here for all to use.

Hope that helps. Glad you're running again though. Plugs eh? Jeez!

H

 

Henry, you really should go into standup comedy. This little passage had me choking on my hot cross bun!

Cheers, SB