Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

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Bally
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Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

Post by Bally »

The engine in my bus is a 1776, mild cam (Engle 110?) 044 heads with dual springs and from day 1 it has leaked a little oil - I think from the fan belt pulley.
Image
I have read that this is most likely due to excessive crank case pressure so was looking to improve breathing. The Scat Porsche Fan style kit from VW Heritage (https://www.vwheritage.com/ac11925085-p ... c-vw-spare) blocks off the normal oil filler point and fuel pump area so my filler is a type 3 style filler into the deep sump. Image
There is therefore nowhere to connect a crank case breather in the 'normal' way. Both rocker covers have a breather port
Image
and these are normally connected to the breather box that came with the kit - I'm told this should provide sufficient breathing for an engine of this spec but doesn't explain why I have an oil leak symptematic of excess crank case pressure.

What are my options for getting better breathing - if I can fit a port then I'll connect it to the breather port on the air filter.

Apologies for the quality of the photos - I'm aware thefan belt has inverted itself but I'm not sure why - it will be replaced.

Many thanks,

Dave
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BJ1
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Re: Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

Post by BJ1 »

Breather boxes are totally useless as they almost always produce positive case pressure.
Try connecting the rocker cover breathers to the air filters - you may have to fit inlet tubes to the filters. That will produce slight negative case pressure which should solve your pulley leak.
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ted698
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Re: Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

Post by ted698 »

Put a stock pulley on it..... most aftermarket ones don’t have the reverse oil scroll on them to keep the oil in....

rodntod
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Re: Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

Post by rodntod »

ted698 wrote:
Sun Jan 21, 2018 9:45 pm
Put a stock pulley on it..... most aftermarket ones don’t have the reverse oil scroll on them to keep the oil in....
This^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Bally
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Re: Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

Post by Bally »

BJ1 wrote:
Sun Jan 21, 2018 3:30 pm
Breather boxes are totally useless as they almost always produce positive case pressure.
Try connecting the rocker cover breathers to the air filters - you may have to fit inlet tubes to the filters. That will produce slight negative case pressure which should solve your pulley leak.
That's interesting - why do the breather boxes cause positive pressure? What's going on to cause that? I've also read NOT to connect to the air filters but I'm disregarding this as the stock engines have been breathing this way for many, many years.

I've already taken the fan stand to the machine shop and it has been modified - I will be connecting this now breather port to the rhs air filter so the engine should now breath as VW intended. Photo to follow once I have picked it up.

I have also discovered I have a sand seal power pulley fitted so this is coming off and I intended to fit a new standard size scat degree pulley but have just found a stock pulley in my stash so may fit that instead...
Many thanks,

Dave
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63 rhd Squareback project

Bally
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Re: Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

Post by Bally »

rodntod wrote:
Mon Jan 22, 2018 11:12 am
ted698 wrote:
Sun Jan 21, 2018 9:45 pm
Put a stock pulley on it..... most aftermarket ones don’t have the reverse oil scroll on them to keep the oil in....
This^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Noted, thank you. ;)
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Bally
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Location: Melburg

Re: Oil leak, crank case breathing and Scat Porsche Style Fan shrouds

Post by Bally »

Here is the solution we came up with for this set up - it was easier to do it this way than to machine the stand for it to come out in the bottom front right just behind the dipstick. I'll run the line along the top of the case and out the back of the fan shroud then up to the rhs air filter:
Image
Image
Image

I have found a stock pulley in my stash so will clean that up and fit it too.
Cheers,

Dave
59 Split Panel Deluxe
63 rhd Squareback project

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