New diesel engine making real knocking sounds when revved up

Mate Im not a mechanic but you shouldnt have a knocking sound and especially on a new motor ?? Unless is diesel knock which is fuel related (air in line) I had this with my 2.8D when I changed the fuel filter one day, it still ran fine but sounded like a big end knock untill my mechanic mate said no its diesel knock (had never heard of that term before) was my first diesel vehicle but must say it did seem to have it as the klms got high (300 thou) but only on start up (only very very minimal) but would go in a few seconds so may have been oil pump starting to get a bit lazy ?? Sold it anyway and still going strong today...........

Bit confusing whether you are idling or revving? Anyway... I would do either until you get it checked, because it certainly isn't okay.

C P

I'am not a diesel mechanic, however I do believe that a 'NEW' diesel engine shouldn't make the noise you are describing.

There is a member of this forum who very recently had a OME brand new from the factory diesel engine fitted to his heap of crap 'Missin Nissin' 3.0l, From initial startup this new engine had an extremely pronounced Rattle/Knock, depending on how your ear heard it.

It was finally diagnosed as a timing fault. The timing had been set one tooth off from where it should have been.

Once re set it was a whole 'new motor' again.

Point being, don't assume that the OME has produced a perfect product. You problem may be something else again, that requires an inspection by someone who knows exactly what they doing.

Regards

DD

I had this happen to a new fully reconditioned diesel engine once before in a hilux. Took it back to mechanic and he said basically tried every bit of B/S under the sun to avoid pulling it down.
First he said Injectors so $800 later (diesel injection specialist) his next best guess was injector pump $1000 later (diesel injection specialist) good thing was at least there was nothing else to pick on so I went back and told this wanker that engines dont knock for no reason. He went over it with a stephescope and reckoned he could only hear normal diesel engine noises.
Basically most will tell you any lie to avoid their obligation hoping your pissy warranty period on diesel engines will run out before it goes bang.

WHAT I FOUND -:

most of these idiots simple send the head to a mate or ather workshop to get a head skim. Good practise but before fitting they fail to centre punch the pre-combustion chambers to spread them tight into place and the skimming process actually loosens them. Not that you would see but enough that after a little running they become loose.
Mine dropped far enough that the piston smashed F@%k out of it disintegrating the piston stuffing the con rod, splitting the bore and destroying the head. I had to threaten court action before he agreed to fix it.

First thing is, get a long bar or screw driver or stephescope and you will here the knock narrow it down to if its from the top end. If so it can only be one of the things I have mentioned. injectors, pump, or pre combustion chambers.