AAZ - Breather pipe?

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Iceworx
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AAZ - Breather pipe?

Post by Iceworx »

Just wondering if when dropping the AAZ in, if the had the block-to-rocker cover breather pipe connected, or if it was blocked off?

The CS I have, its blocked off, but not sure what to do for the best on the AAZ :)

Thanks
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Re: AAZ - Breather pipe?

Post by syncroandy »

There is a theory that with hydraulic-lifter engines at 55 degrees, the extra breather pipe is useful. Without it, oil returning to from the head to the crankcase via the drain galleries has to fight against blowby gasses coming the other way. The extra breather reduces this problem, and the chance of unwanted buildup of oil in the head, where it could in extremis exit via the breather and get to the turbo. VW stuck to solid lifter engines in the T3 and some have speculated the oil return issue might be part of the reason.
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ringo
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Re: AAZ - Breather pipe?

Post by ringo »

Hopefully someone with better knowelege than me will comment...

After reading up on the subject when i went AAZ, i vented the block to the doughnut on the rocker cover and then vented the other side of the doughnut to atmosphere via a small cone filter.

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Re: AAZ - Breather pipe?

Post by ewenmaclean »

Andy's explanation is spot on - I really wouldn't blank this off. There is a choice of pipe that connects the block to the CCV - one with an oil separator and one without - mine has the oil separator and it is often very oily - the oil then goes back into the crankcase. The CCV valve has a regulator spring and diaphragm inside it which allows the blow-by gasses past without too much oil going directly into the induction system - if you don't have the secondary pipe then your CCV valve will most likely get clogged up and then you'll have crank-case pressure build-up which can produce oil seepage just about anywhere...

Ringo's suggestion of a vented pipe is good too - some use a "catch can" - I don't do this as it tends to make the engine bay a bit oily, and the amount of oil in the blow-by gasses passed through a properly functioning CCV valve should never be enough to cause runaway.

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Re: AAZ - Breather pipe?

Post by Domb18 »

Hi guys. I'm the new owner of an AAZ T3. It has the breather removed and blanked off. I'm looking to reinstate with a filter of sorts. Where could I get the part's?

Many thanks

Dominic

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