This Lancia Fulvia Series 1 coupe is almost perfect. The owner is a diehard Italian car enthusiast and only recently acquired it. Unfortunately, after a few hundred miles of use, a nasty oil leak emerged.
All clues point to a leaky rear main seal. So we removed the transaxle, clutch assembly, and flywheel. Here is what we found. The seal wasn’t worn – it was split entirely into two pieces.
It became apparent there was a clearance issue between the flywheel and the rear main seal. So, the first place we looked was at the crankshaft thrust bearings, and to check the axial play – it was within the factory specs. The seal, bearing a large USA stamp, is clearly an aftermarket shielded type (shielded referring to the reinforced steel outer casing). It was also slightly taller, and we determined this to be the problem.
While looking at the flywheel closely, galling caused by the steel-reinforced seal is visible on the flywheel chamfer.
As always, I am little light on photos from this job. But, the image above shows the flywheel after we machined the inner chamfer to provide some additional clearance and clean up the galling. From there were installed slightly taller crankshaft-to-flywheel spacer, setting the crankshaft’s axial play on the tighter side of the factory specs, and we installed a new non-shielded rear main seal.
Back on the road. This Fulvia S1 Coupe drives remarkably well, and more importantly, keeps the pavement dry!