Editing Crankshaft rear oil seal (section)

=== Symptoms ===
When the crank seal goes, the oil will collect at the lowest point between the sump and the gearbox bellhousing, then tends to run along to the driveshaft and gets spread around everywhere by that, so it's hard to tell where it's coming from.  Trouble is that if it's leaking elsewhere it will also collect at the lowest point between the sump and the bellhousing ;-(

Worth getting a [[leakdown test]] done to see if you do have worn rings/liners.

The other thing to check are the breathers on the cam cover. Inside the cover are wire wool filters that might be clogged up with oil causing the crank pressure to build up.

Get the car up high and use a mirror to have a good look all around the block for evidence of leaks, if you cant see any then it's likely to be the crank seal. While the box is off you'd be a fool not to change it - even more so if you're fitting a light flywheel! The seal is RTV'd in place and the manual instructions are good - you need to check the seal after a few minutes since it can lift out after fitting. Best to holt it in place for a few mins immediately after fitting, then go away for lunch and check that its still well in there and parallel when you return.

Take the hose off between the airfilter and the throttle body, and see how dirty the throttle body looks. If theres excess pressure in the crankcase then you will get a lot of oily mess on the back of the butterfly.

High pressure in the crankcase is usually the cause of the crank seal leaking significantly.