Breather system

[Aaron1776]

Hi guys at last I got my engine back
And got it fitted and running yesterday
Had a couple of oil leaks nothing major
But got me thinking about some sort of
Breather system
What would you guys recommend
If any

Thanks chaps

[Doon L001]

I put one on mine because pushing it round a roundabout I filled a rocker cover with oil and put the warning light on, it then took ages to get back to the sump.  A breather box doesnt stop it going there but does help it run back.  I put an extended sump on to stop he sump running dry.

I use a simple bugpack one with connectors to the breather on the filler neck and one to each rocker although I have used connectors and hoses from Pirtek and modified it a bit, just better quality although they are OK out of teh box.

I just happen to have a brand new one unopened lying around, I couldnt find my old one so ordered a new one it then found the old one.
Dave

[AndyRobinson]

Been looking at this one myself. Too and am having it sorted as we speak!

Heritage insisted that I have one fitted on their engine BUT get this, the rocker covers they supply and fit to that engine are just clip on ones and don't have provision for the pipework. To begin with all I had was the crappy little air filter up on the oil filler like most. And there is certainly a bit of evidence of oil (vapours) coming out of it - that side of the engine is a bit grimy.

Did think of the breather kit (which I also bought but still have it all wrapped up), but instead have opted to a pipe from the filler instead of that small filter and going into the air filter of one of the carbs. Essentially what VW used to do. I think that will be the best option. If its really necessary to use the bolt-on rocker covers and the breather kit fitted then so be it but I think Carb air filter is the solution.

[snoopy]

breathers are all about air flow and having less restriction that causes pressure in the crankcase Dave Fisher stated heritage said they were needed on anything over 1600 to keep the warranty.
I would think a new built 1641 breathes less than a well worn 1600.
however if you build a motor to use higher rpm the pressure will be up over a standard 4500rpm motor.
it is possible to fit tubes in standard rocker boxes but most upped motors also up the bling so alloy covers fit both needs.
if you are running an electric fuel pump you could convert that crankcase hole to a breather insted of the rocker box system.
I cannot recall larger vw aircooled motors or water pumpers having much extra in the way of crankcase breathing my 1700 never had rocker vents as standard just a breather by the filler and that was 5500rpmish from the factory.

[Doon L001]

The benefit of rocker breathers is that assuming we drive this light tuned vehicles a little more robustly that VW intended then we will be pumping oil into the rocker covers and preventing it running back through heavy cornering.  I managed this on a roundabout and had the oil light come on
Although breathers wont stop this happening on their own they will allow the oil to drain back into the sump faster once you stop driving in circles by letting air into the covers rather than it having to find its way up the push rod tubes as the oil is trying to come down.

Try pouring oil from a top up can with the lid screwed on and air has to get in via the spout, then take the lid off and you will see the difference.

I kept the standard VW covers and cut holes for good quality fittings.  As the breather isn't under pressure you don't really need any better than comes with the kit but I prefer to do a job once and well.
Only thing to watch is where you put the fittings as they obviously have to clear the rocker assembly.

Dave

[Aaron1776]

thanks guys
i have gone for a deep sump as well and with the external oil filter
it needs about 6 ltrs  i am using a facet fuel pump so should o just fit a filter
to the blanking plate or do i still need to fit breather pipes to the rocker covers 

[Doon L001]

Aaron
where are you?

It sounds as if you would benefit from seeing a fitted breather system to help you understand what they actually achieve.

With a deep sump you are unlikely to get oil starvation from cornering but will still need to relieve pressure in the crankcase.  The original VW design was a pipe from the oil filler to the air filter (I think) so it got a little bit of negative pressure to suck the fumes out.  Most people fit a small filter to the oil filler connector to let the crankcase breath,  It is almost inevitable that over time a small filter with oily fumes going through it is going to get mucky and possibly leave traces of oil around it, particularly if it is fitted pointing down from the filler neck rather than up.

So in the end it is just your choice whether you fit a proper breather unless your engine is a real stonker..

Pros 
    Oil flows back to the sump easier from the rockers (also gets there easier under cornering as the air can get out)
    It is 2 more routes to relieve pressure
    Less chance of oil leaks around rocker covers by reducing pressure (originals dont leak if they are straight and properly fitted)
    No potentially mucky filter dripping on the engine
Cons 
    More plumbing and routes to find for pipework
    Holes to cut in rocker covers
    More joints and potential oil leak sites
    More to disconnect to remove rocker covers or engine
    They do need a wipe out occassionally and if they have a filter it needs to be cleaned now and again

So over to you
Dave

[Aaron1776]

I'm in Basildon mate all it has at the moment is the filter on the filler neck

[Doon L001]

Now I know which Aaron I am talking to, I am the one in the lwb Doon on last years Ace run.  Loved your buggy.

[snoopy]

diversifying a bit but to stop the oil surge on hard cornering and the light coming on you need to keep the oil from moving away from the pickup pipe.
fitting extra long pushrod tubes to reduce the oil entering them and thus keeping more up against the side of the case and thus in it also fitting baffles in the sump helps keep the oil in place but as stated using an extra deep sump conversion negates this as the oil in the lower part is pretty well captive.

[Aaron1776]

Yes it's me Dave 
I have been looking at diffract systems
But just can't make my mind up 

[Zebethyal]

breather connections on my 2.0 Type IV:

2.0 Type IV by Zebethyal, on Flickr
I have similar ones on my 2332, they connect to this breather catch tank, which can hold up to a quart of oil if necessary:

FrancieBuild04 by Zebethyal, on Flickr
The third connection is from when I had a Berg 5 gearbox that also had a breather line.

[Aaron1776]

breather connections on my 2.0 Type IV:

2.0 Type IV by Zebethyal, on Flickr
I have similar ones on my 2332, they connect to this breather catch tank, which can hold up to a quart of oil if necessary:

FrancieBuild04 by Zebethyal, on Flickr
The third connection is from when I had a Berg 5 gearbox that also had a breather line.

Spot on thanks mate