standard exhaust performance

[Dave Mann]

A decade or so ago I acquired a job lot of assorted Seven parts which included a pair of lip seals for the diff, so the next time I had an axle down I fitted them. The axle went into service and I found it was leaking oil from the vent (RN with banjo diff case with a vent pipe on the case), so I put a short piece of hose on the vent to direct the drips onto the road. The next time I looked the whole of the rear floor was covered in oil, so the air flow under a Seven is anything but what you would expect but at least it was oil which protected the floor from rust and not exhaust fumes looking for a way into the car.
The solution was to put less oil in the diff, but it also revealed that the previous felt seals weren't as good at sealing as the lip seals.
Our drive has a slight incline towards the road, not enough for a Seven to roll down but take the brake off the modern and it starts to roll with it's wide tyres but of course it has lip seals in place of the Seven's felt seals.