Type IV top casing breather

Rick L. · Post by **Rick L.** » Fri Jun 25, 2004 1:37 pm

Hi...question....i just got a type 4, and on the top of the casing there is the plastic cap for it looks like, the oil fill, where could i see a picture of the breather, and where could i get the parts? wondering if there is a lot of pressure escaping from that area? also, had vent lines made from the cylinder heads for venting, but not tooo sure on the oil breather deal!!
h-e-l-p-....thanks!!
Rick

minty73 · Post by **minty73** » Fri Jun 25, 2004 3:08 pm

it sounds like you are talking about the timing mark cap, have you undone it and had a look in? you should see the fan blades. the oil filler cap tends to be on the ednge where the engine lid shuts. 2 caps, 1 for dipstick and one for filling.

thats how it is on my 411 variant

raygreenwood · Post by **raygreenwood** » Fri Jun 25, 2004 7:46 pm

No, the variant only uses the long dipstick that is right under the edge of the rear hatch. The 2 door and four door sedan are totally different. The sedans use a black steel square brather that is held down by a spring "latch" or bale. They have a round screw cap on top of a funnel that say "Oel" or "oil" on top. That square metal part under the oil cap is an active part of the PCV system. Yes...all of the crankcase ventilation come out of that area so...the cork gaskey between teh case and the square black metal box must be perfect. Also the gasket in the round cap must be perfect. The breather hoses in the heads....are the INLET from the air cleaner. The inlest air then pushes crankcase gases through to the top of the case where they are sucked out through the PCV valve and into the plenum. Ray

Class 11 streeter · Post by **Class 11 streeter** » Fri Jun 25, 2004 8:48 pm

Ray, isn't the setup you are talking about, the oil cap and metal box, the same as used on the 914 engine?

raygreenwood · Post by **raygreenwood** » Fri Jun 25, 2004 10:55 pm

Yep! Thats the one. Ray

minty73 · Post by **minty73** » Sat Jun 26, 2004 1:46 am

fair enough, didnt realise it was variant only (i am new to all this)

DeathBus · Post by **DeathBus** » Sat Jun 26, 2004 4:42 am

raygreenwood wrote:No, the variant only uses the long dipstick that is right under the edge of the rear hatch. The 2 door and four door sedan are totally different. The sedans use a black steel square brather that is held down by a spring "latch" or bale. They have a round screw cap on top of a funnel that say "Oel" or "oil" on top. That square metal part under the oil cap is an active part of the PCV system. Yes...all of the crankcase ventilation come out of that area so...the cork gaskey between teh case and the square black metal box must be perfect. Also the gasket in the round cap must be perfect. The breather hoses in the heads....are the INLET from the air cleaner. The inlest air then pushes crankcase gases through to the top of the case where they are sucked out through the PCV valve and into the plenum. Ray

MAke sure that gasket is A#1 top shape, or you will be chasing oil leaks from here to eternity, I KNOW, I had a blown one myself!

Rick L. · Post by **Rick L.** » Sat Jun 26, 2004 6:10 pm

Big Thanks.....this actually goes to a race car, super vee, which is the same as the 914, appx. 200 hp. Parted with the rebuilder on not the best of terms....but the device I speak of, is the 'round' one on top of the casing of the t4, like an 'L', gasket missing for the bottom part that fits to the casing, assume it is the cork? I just snagged a round o-ring, better find the original it sounds, but went to the veedub dealer, he says they do not even carry the parts manuals anymore...but the other half of the 'L' the top half I was going to connect to the top of the oil tank which when filled is down a ways, so thought that might work for enough space to breathe? I do appreciate all of the help!! There seems to be an oil leak still..after the vent lines to the overflow bottle, but I am going to a vw/porsche swap meet/car show tomorrow morning, maybe I can find something there?
Thanks again, I apprecaite it!!
Rick

raygreenwood · Post by **raygreenwood** » Sun Jun 27, 2004 1:13 am

You should look at the crankcase ventilation routing from the stock injected cars...411/412/914. There is nothing that beats it. If you do not ventilate these cases at least as well as factory...they will leak oil from over-pressure. It must be ventilated...flowing clean air through the heads...and sucked from the top of the crancase through the excellent factory baffel....with manifold vacuum ...not air-cleaner vacuum. Ray

Rick L. · Post by **Rick L.** » Sun Jun 27, 2004 7:41 am

Thanks Ray...I'll look a little later this morning, and take my camera!!
Rick
(the car has the dual webers, with upright air cleaners, and the compu-fire ignition dix9, 65,000 volts).