divil

I'm trying to figure out why my balance shaft seals started leaking again very soon after replacing everything. After tearing it down, I see that there's oil right below the place where the front balance shaft housing bolts on. That makes it look like it was leaking from there. Is that likely, or would this just be because the main seal leaked and it flowed back underneath the support piece? Either way I don't see why it happened so I'm interested in anything I can do to prevent it again. There is nothing obviously wrong with the o-ring that seals the housing other than age.





The mylar seals have degenerated into almost nothing:





Is that normal? Again, I don't see what I could have done differently to prevent this. It's been about 3.5 years since I replaced them but they leaked again soon afterwards. At the time I replaced absolutely everything seal-related at the front of the engine.

thomasmryan

My lower seal lasted about 8k miles/24 months. A kit, hamburg tech, seal so junk going in but the wear pattern on the flutes was inconsistent.
I assumed the bearing shells for the balance shafts are approaching their wear limit and allowed just enough movement to foul the seal.

divil

Thanks. I was just looking at the PET diagram and I noticed something I've never seen before - it shows a sleeve that goes inside the housing (I crudely circled it in this screenshot). It's described as "bearing sleeve", part number 944 101 125 02. I just had another look at what I just removed from the car and sure enough I can see this in each balance shaft housing. I had no idea this existed. Do I need to replace it? I'm sure it didn't come with the Paragon front seal kit I used last time.

thomasmryan

The balance shaft has split shells in the rear near the weights and a cylindrical bearing shell in the front. I got a set from Ian but have yet to install them.

I might 3d print a balance shaft seal installer the next rainy day. I can never get them to go in straight so I assume this tweaks them enough to fail. The practice 'hamburg tech' seal has half the number of flutes as some of the porsche, erling and kaco seal pictures that have been posted.