Multiple Oil leaks - Blow by Gases?

bertible · #1 12-31-2011, 01:40 PM

My 01 Allroad has performed with stellar service for 200K km (120K miles) but started leaking oil about 10k ago. This was the typical burning smell in the passenger compartment. So I did the valve cover gaskets along with the timing belt (a "bear" of a job for a DIYer). The leaks diminished but did not go away. I ended up redoing the cover gaskets being more careful to put sealant at the right angle turns at each corner of the gasket. The second time, I also replaced the aft cam plugs, at least one "seemed" to be a source. The leaks seemed to end for awhile (no more smoke, as no more dripping onto exhaust)

But Now, another leak seems to have sprung from the front of the engine. Can't tell if a main crank seal, or a cam seal (I didn't want to go that far when I did the timing belt).
This is like the little Dutch boy plugging holes in a dyke with his thumb. As soon as one leak is fixed, another springs up.

In other cars, all these leaks springing up could be a symptom of too much crankcase air pressure from Blow-by gases. The 2.7L APB engine doesn't seem to have a PCV Valve, which would be the normal quick fix. I've blown air through the tubes that go from the valve covers to air tubes (right on top of engine) and they seem clear. Does anyone else have experience of these recurring oil leaks, and whether there are other solutions than continuing to replace seals/gaskets?

Thanks!

kentetsu · #2 12-31-2011, 07:28 PM

It sounds to me that you are on the right track. The PCV valve/system on these motors is, for some reason, called a spyder hose (or pipe, or something).
.
I had mine freeze on me last winter, started blowing smoke out the tail pipe. Any sign of smoke coming out of the exhaust?

swamper8 · #3 01-02-2012, 10:11 AM

If you didn't do all your CAM seals at the same time, you probably should have. Sound like you might have only done a couple? Typically the VCG's/CAM seals are all done at the same time to avoid what you're going through right now, the "little dutch boy" syndrome. However since you have a 2001 you may want to check to see if you have the updated oil cap. At some point Audi updated the filler cap to a vented style. Common topic that's brought up when people ask about oil leaks. If your cap is original, I'm pretty sure you don't have it. Google the topic to get PN's etc to cross ref. the PN on your cap to the vented cap.

Updated oil cap at ECS:

Audi All Road 2.7T > Search > Oil Cap > ES#251141 Oil Filler Cap - Update Version - 078103485F

bertible · #4 01-08-2012, 01:23 PM

Thanks for the hints,
I did not replace any valve seals (either the little gaskets, or the shaft seals). The timing belt job was such a monster, I just wanted to get it back together. Could of, should of.... 20/20 hindsight!

I think I'll replace the spider hoses, the air limiting valve at the top had a crack, current sealed with gorilla glue. The oil vent cap is definitely the original old style. I think I'll try that first.