L295 injector pump

Hi All,
I'm the newest nubie (at the moment), I looked for info on the 295 injector pump, but found nothing that related to my problem.
Diesel is getting past the injector pump into the sump, when I first got it, the tank was empty and the sump was FULLLLLL! to just under the rocker box. drained and replaced oil but altho' I turned off the fuel tap after a brief run, once stopped what was in the pump drained down into the sump again.
Any help would be much appreciated.
Also, how does the pump come off of the motor........do you have to remove the timing chest?
Thanks,
Rob.

Thanks Wolfman,
The manual was certainly helpful, I'm used to dealing with self-contained pumps where the camshaft has oil seals at each end.
Lister engines have (used to have)pumps that altho' they were close coupled were none the less self-contained with an oil seal at the front preventing the transfer of diesel to the sump.........kinda hoped this would be the same,
back to the drawing board.
Rob.