Noisy new pump

Had new Diesel pump fitted to Disco 2 2003, has been noisy since fitted, makes various levels of noise on start up, sometimes very noisy, engine has been cutting out once a week whilst driving, have managed to pull over safely and given it 15 mins to settle and starts again after a few goes and is fine for another week or so, any ideas, mechanic friend has ordered a another new pump to replace new one he fitted, any ideas? Should pump make quite a bit of noise for 30 seconds on turning key? Thanks

You should hear it from outside with engine off and ign first turned on, any louder than that and there is an issue.

In my experience, aftermarket pumps are noisy and garage. I always fit OE lift pumps, to eliminate potential future issues.