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lower balance shaft seal area leak - expert input needed!
Background: I replaced 'all' of the front seals about 5 years ago, but since that time an oil leak has remained. I've finally gotten around to taking things apart to try to pinpoint the source of the persistent leak. The photos shown below tell the story. I think the most likely root cause is the o-ring seal on the back side of the lower balance shaft cover, but I can't rule out the oil pump housing or the oil pan gasket. What is mystifying me is that all of the other seals that I replaced look perfect, and so why would this lower balance shaft seal be compromised somehow.
Looking for anyone who may have experienced something similar after replacing the lower balance shaft o-ring and advice on what may actually be causing this. I'd prefer not to go further and redo the oil pump housing seal and the oil pan gasket... but maybe that's the wise thing to do? Thanks!
The red outlined area shows the oil leak path. It's slightly 'green' since I used UV dye in the oil. In the process of removing the LBS cover. Note (red outlined) that the lower bolt has oil present on it as I pulled out the bolt. (Shaft seal looks great). Red outlined area is the oil leak path. Yellow circle shows where the bolt with oil on it was. (Note that oil was not dripping from this bolt area when assembled). Suspected o-ring seal. But I don't see any damage.
Hard to tell from the pictures, but it doesn't seem like the o-ring is the issue. Maybe just the housing seal to the block itself?
If the oil leak is from the threaded bolt hole, I would suggest putting high temp compatible oil sealant on the bolt threads. The lower BS is in the internal oil stream with the tapped hole into an high pressure oil cavity
Last edited by T&T Racing; 09-03-2020 at 08:56 PM.
I've decided I'm going to 'bite the bullet' and redo the oil pump seal and replace the oil pan gasket. So I'm in for quite a project.
While I'm at it... what else should I replaced proactively while I have the lower hardware & oil pan off of the car?
I've read about replacing the rod bearings... should I do that 'no matter what' or based on inspection? The car has 68k miles.
Thanks.
09-01-2020, 06:24 PM
lower balance shaft seal area leak - expert input needed!
