Amazon: oil in air filter

[woodman]

Hello

I'd been wondering why the area of the engine bay around the steering box was getting very oily. Now I've noticed that the air filter is soaked in oil, which it appears to be drawing up through the rocker cover breather hose, and then throwing out through the air filter box. It's going through about a pint of oil every 400 miles, most of which I'm guessing is coming out this way and then either going in through the carb and being burned, or dripping out.

I want to change the air filter but there seems little point until I know how to stop it drawing oil. Any thoughts, folks?

Cheers.

[Ron Kwas]

Woody;

Oil in steering box area is likely due to a leaking seal on the box and this has little to do with oil in air filter...that is more likely due to excessive blowby or problem with PCV system**...I'd sniff oil at steering box area...that definite hypoid oil smell confirms its source as the steering box.

** See: http://www.sw-em.com/pcv_diagrams.htm

Cheers from Connecticut!

[woodman]

Originally Posted by Ron Kwas

Woody;

Oil in steering box area is likely due to a leaking seal on the box and has little to do with oil in air filter...this is more likely due to excessive blowby or problem with PCV system**...I'd sniff oil at SB...that definite hypoid oil smell confirms its source as the steering box.

** See: http://www.sw-em.com/pcv_diagrams.htm

Cheers from Connecticut!

Thanks Ron. Interesting link - I can't open the images though, was there an answer to the question of fitting a separate filter on the filler cap to eliminate the hose to the air filter?

By the way, virtually no oil around steering column shaft into SB, or beneath the SB - most of the oil is on the ledge on the inner wing and further up the steering shaft, which to my eyes looks like it's dripping from the bottom of the air filter housing. And my sense of smell is rubbish! But I'm quite happy to be wrong on the source of the oil!

[classicswede]

Some pictures of teh air filter and all the connecting breather pipes would be helpfull

[woodman]

Originally Posted by classicswede

Some pictures of teh air filter and all the connecting breather pipes would be helpfull

Yeah, point taken! Here are some pics - anything shiny is oil! There is a bit of emulsion in the rocker-air filter hose, but no more than I've seen in most old engines that perform fine.

Looking at Ron Kwas's link, if what's supposed to be happening is that the crankcase breathes by drawing air from the air filter box, and what's actually happening is oil is being drawn the other way, then the suction on the inlet manifold is a lot stronger than the draw on the crankcase ventilation. When I take the oil filler cap off there is some vapour (even after a short run) but I can't tell if it's hot oil or steam. Performance is fine and the head has been recently overhauled/pressure tested etc so I can't imagine there's anything seriously wrong.

I suppose one test would be to re-route the breather hose into an external drip tray and see if it still blows oil if there's no suction in the hose from the inlet manifold?

[ClassicVolvoShop]

Well,
I think pictures of the complete engine from, say, 3-4 feet away is what's wanted.. not the filter itself - to try diagnose if your tubing is setup wrong etc.
One thing is for sure: The tube TO airfilter is to DRAG clean air - so if oil is pushed TO airfilter - the pressure/circulation is completely wrong, see?

Try clean all your parts in the PCV (positive crankcase ventilation) system: tubes, oiltrap, vacuum-'bolts' (what do you call them? in/outlets?) - those screwed into the manifold..

Have you switched around the tubes for PVC and brake servo? Etc. - that's what "we" could determine from pictures etc..