My mini: 1981 Mini HL, 998 with 12g940 head, MG metro cam and twin hs2 carbs. Recently overhauled engine.
The problem: oil leaks.
Despite a limited overhaul (new seals all round), my engine still leaks oil. In fact, the leak seems to move around, so as I 'squash' one leak, it finds somewhere else to come from. Given that most of the oil seals in the engine are new (timing cover, red clutch seal, differential outputs and gearchange), I'm thinking this is due to crankcase pressure, (the pistons and rings weren't changed).
Currently, the engine has a breather on the timing chest, and I've also added one to the rocker cover, however, these vent into the airbox as my twins don't have the breather connection. I'm wondering whether this is 'active' enough to 'suck' on the crankcase pressure. I could install the PCV valve system, but this would be non trivial, as I'm already using the manifold connection for a brake servo, so would need to do some drilling and tapping or similar.
So, are there any other causes of oil leaks which it's worth investigating first? Do I need to find a couple of twin hs2 bodies to replace the ones I have, or is it possible to drill my existing carb bodies to add the breather connection? If so, are there any drawings to show where the hole should be, as I understand it's quite specific in order to get the 'right' amount of vacuum?
Any thoughts welcome - ideally cheap ones - would rather not have to have the engine out again 
John
