29/08/2026
BMW Sump Seal Replacement
We recently repaired the common (for age and kilometres) issue, of a leaking BMW X1 sump seal. As BMW famously designed their engines to be mounted at a 30 degree slant to lower the centre of gravity, lower bonnet height and improve torque balance, while providing increased room for the intake system, the right hand side of the seal remains below the oil level.
This can lead to common leaks after 100k km or so, as the polymer seal hardens and the plastic sump expands and contracts at a different rate to the block.
The fun part is the need to remove the subframe and steering rack to access the sump, which therefore requires the engine to be supported from above. The resourceful BMW engineers thoughtfully provide a threaded hole at the top of the engine where a genuine BMW tow hook can be used to attach to the engine support beam. Simple....except on the X1 N20 the tow hook supplied with the car does not match the thread on the engine !!๐ Thankfully time saved by borrowing the tow hook from a neighbours BMW 3 series race car ๐.
