Hi all. Just to update, it may be just bad luck or stupidity on my part, but I've had serious problems getting my pump to seal correctly since fitting the new seal kit (not the kit from ebay linked above, I bought locally from a diesel specialist).
High pressure side seems ok, the engine starts and runs without high pressure fuel spraying everywhere. The problem is apparent with the engine off and ignition on - while the electric feed pump runs, fuel leaks out from the 'head caps', so the leak appears to be only on the low pressure side.
My research online suggests the tightening sequence and torque for the pump heads is extremely important. Tighten evenly to 11 lbft, leave it to settle for 10 mins, then proceed to torque evenly to 18 lbft. But even adhering strictly to this method, and after multiple attempts over the weekend, my pump still leaks. The bolts themselves are actually rated for a bit more torque than this, but I'm just not willing to risk it without reliable documentation.
I've since booked in with the same specialist I bought the kit from. He's offering to rebuild the pump himself and do a pressure test for me. £60 +VAT was the estimate given on the phone, so really not bad at all if that's to be the final figure. TBH if I'd thought it could be that cheap initially, I'd have probably just gone with that. £72 is nothing compared to the stress and hassle I've had trying to do this myself while maintaining absolute cleanliness. (Not to mention hair loss when it didn't work for the fourth time around lol)
While these Bosch pumps are mechanically very simple, tolerances are minute. And as varesecrazy rightly says, any contaminants introduced during the overhaul precess have the potential to destroy the pump, and very likely the injectors too.
