How does this happen to an air filter?

Bit confused on this one!! Was out on the Salisbury Plains a few weeks ago and just got around to fully checking everything over, pulled the air filter out and was met with this -

(04 TD5 110)



The lower half of the box was no where near as dirty, some debris and a little muck but nothing like the above. Checked the snorkel from the head down, again little muck but nothing serious.

Pulled the turbo intake pipe off and that was coated in a similar way to the last picture but not as bad, same for the MAF sensor.

If the bottom of the air filter was dirty then I would understand, but how can the top be that filthy and the bottom be almost spotless?

All I can think of is the Pipercross air filter isnt sealing 100% against the airbox and the engine is sucking in some unfiltered air from the corners (where its mucky)

The 110 still runs perfectly well, no difference there.

Bit of extra info. My intake consists of an MOD steel snorkel with a 3" flange welded onto the bottom which has a 3" induction hose sealed to it using Sikaflex and a jubilee clip, this runs direct to the curved reducer section of the TD5 airbox sealed with Silicone & a jubilee clip. The airbox is then sealed up internally and externally.

id pull box out completely and ensure top and bottom are sealing together fully it looks if yours isnt

Thats what I'm thinking, slightly concerning.

Did you ever try the stall test?

Cheers

I did indeed, took a while but eventually did. Going to do it again now.

I've got the same filter in mine and I'm sure it doesn't seal properly. Can hear a high pitched whoosh on the motorway when I accelerate. Like a **** cone filter on a hot hatch. I'll pull the box out the weekend

Tested with the standard filter, stalled in less than 30 seconds.

Got to wait for the pipercross to dry before I can test that

bankz5152 said:

Tested with the standard filter, stalled in less than 30 seconds.

Got to wait for the pipercross to dry before I can test that

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I haven't got a snorkel but if I take the pipe before the airbox off the inner wing (disco 2) and cover that it should stall?

1988smithy said:

I haven't got a snorkel but if I take the pipe before the airbox off the inner wing (disco 2) and cover that it should stall?

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If you are going to do it, then use something sturdy to cover the tube, not your hand or some other appendage..... As an example I find the haynes manual is very useful for this when testing my snorkel.

Cheers

neilly said:

If you are going to do it, then use something sturdy to cover the tube, not your hand or some other appendage..... As an example I find the haynes manual is very useful for this when testing my snorkel.

Cheers

Click to expand...

I'd like to think I wouldn't have but thanks for the heads up! Haynes manuals on the back seat actually...

So stalls out with the pipercross fitted too, takes a little bit longer but still stalls. So it must be sealed? Unless the leak is so small it doesnt provide enough air

Think what Ill do is swap to the paper filter for off roading..