'01 S4, 16k mi, mostly stock.
I've got a slow leak that appears to be coming from the breather valve. I've also heard this is a somewhat common problem. Here's my questions:
The O-ring from ducati has to be ordered and will likely take a while but if I can find an oil resitant o-ring of the same dimensions is that a suitable alternative?
Is it likely that I'll have to replace the breather valve itself or is it just a bad seal, ie., replace O ring, tighten/re-seal and I'm okay?
Anybody know what size wrench I'll need to to get at it? I know I'll need to get one but I'm not sure the size.
Thanks as always!
As long as the breather body hasn't cracked.
Mine had an alloy washer. It was leaking as it was loose, but strangely the clamp on the hose was tight, so I don't know how it backed off. I added semi hardening Permatex aircraft gasket sealant to the washer and mating surfaces and tightened it with a small C spanner. Hasn't leaked since.
Clean the breather and surrounding area well. Then spray with an aerosol powder, like foot powder. Go for a ride. The oil stain will lead you to the leak. Or. if there are a lot of miles on it, replacing may not be a bad idea. I replaced mine at about 40K miles, it was weeping through the seam. It was pretty nasty inside.
That foot powder trick is one of the best left field, diagnostic tools around. The first time I knew of it was on this forum.
Who'd have thought; foot powder! [clap]