crankcase ventilation

bikecrazy Casual Dubber

24 posts · joined Sep 2010 · 16 Mar 2011, 7:12 pm

#830960

i have discovered that vw's dont like having no air filter (read, it got excited and blew oil everywhere)

anyway i want to replace the air filter with something different hasanyone had experience with breather boxes do they help etc or is best to use a sand seal and remove the ventilation system?

grumble Son of Jim - Creator of Good

2,672 posts · joined Jun 2008 · 16 Mar 2011, 7:35 pm

#830966

The little oil bath air filter fitted to the VW is one of the most efficient units available,over the years I have seen a lot of sports filters fitted in their place and the dust has got through and cut the rings out in no time. Whatever you use make sure that you still let the crankcase breathe so the pressure doesn't build up in the case as this was more likely blocked off when the cleaner was removed.

waveman1500 Also rides a Honda

1,346 posts · joined Dec 2009 · 16 Mar 2011, 10:10 pm

#831013

I generally tend to agree that if you've got a stock carburettor, then the stock oil-bath air cleaner is the best thing to use. They certainly flow more than enough air to not restrict the tiny carb which is under there, and as mentioned they filter the air very effectively and serve as a good place to separate out and collect oil from the crankcase.

1972 VW S-Bug - For Sale!
1968-onwards Beetle panels and glass for sale

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 16 Mar 2011, 10:32 pm

#831015

bikecrazy wrote:i have discovered that vw's dont like having no air filter (read, it got excited and blew oil everywhere)

anyway i want to replace the air filter with something different has anyone had experience with breather boxes ? do they help etc or is best to use a sand seal and remove the ventilation system?

Hi
You Have to Vent the engine pressure out somewhere...
If You block off everything then oil will come out the dipstick hole... You need to get the case machined for a sand seal..
having a seal at the pulley would be great....
BUT
You still Need to let the pressure OUT....
I've thought about breather boxes.... and hoses to the tappet covers...
and they seem like a good idea....

if they are are set up correctly they should collect all the moisture that collects under the oil cap...

I did try a nice chromed air filter but have read that when tested, the VW oil bath air filter is the BEST....
NON Restrictive...
air flow is Excellent into the top of the carburetor...

I have seen many people go from chrome back to the genuine VW filter...

LEE

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- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

modnrod Fahrvergnugen

978 posts · joined Mar 2011 · 17 Mar 2011, 3:20 am

#831019

I used 5/8 hoses from the top of each rocker cover at the front into a breather box on the firewall, also put in the breather hose from the filler stand. Used a push-in breather (shiny!), no more oil mist, that was on a mild 1640, and warm 2L Kombi panel.

If your engine starts spinning up past 5000, then you might need something a bit more effective. I've used these on hi-po bikes to great effect:
http://www.et-performance.com/normal.html
(Am I allowed to post a seller address here? If not, oops!).
For all the racers out there, yes they work brilliantly, and yes, they are MUCH more effective than just a simple PCV.
😎

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 17 Mar 2011, 11:34 am

#831060

I have found that using 1/2 id hose...
that some oil is blown up the hose....
using even smaller hose was much much worse....

so 5/8 hose would be ideal....

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

vwo60 Veteran Volks Folk

2,036 posts · joined Feb 2007 · 17 Mar 2011, 2:50 pm

#831082

I run a centre mount K&N breather tower connected to both tappet cover's and ther breather outlet on the oil filler, motor is a 2054 and i never have any issue's with crank case pressure, it run's 1/2" id hose and a sand seal.

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