new balanced injectors nailing (video included! )

[pdrayton]

I put new injector nozzles and balanced them all to 140 bar (it's a 92 300D 2.5 turbo.)

It had been nailing a little bit, but now it is nailing a LOT! But only when idling. When I pull off it goes well - very smooth and good power. At high revs it puffs black smoke out (Like in an italian tune up).

I tightened down the injectors a bit more to be sure they weren't the cause of the nailing, but still, they're nailing. At least I think it is nailing. It could be the hydraulic lifters. I replaced about half of them 6 months ago, and they seem to have been fine since then, but you never know, it could be them, but why would they suddenly get loud when I balance the injectors?

The old injectors where at about 1600 psi (110bar - very low, these are 135-145 bar injectors) and now they're at 140bar, so could that be doing it?

The other thing I'm thinking it could be is that I'm using the mobil 1 extended synthetic oil and it's not specifically rated for diesel. But it was making noise before I used that oil, just not so much.

Anyway, I probably needn't have blabbered so much, the videos will tell all.

The other possibility is that the noise is from the splined collars that hold the threaded piece that the injector screws into is leaking on 2 of the injectors.

Also, the nailing is hard to locate. It sounds like it is coming from the whole top part of the engine - I untightened each injector line in turn and the noise continued. Also, removing the oil cap didn't increase the noise ( I thought noisy lifters would be more noisy with the oil cap off).

OK, enough blabbering. Please you with the experienced ears, have a listen and a look and tell me what you think,.

Last blabber - injector 1 needs a new threadfor the injector to screw into, so that could be contributing. I tried to buy the part, but the dealer couldn't find it and when they found something it looked like the wrong piece. I'm talking about the piece that the injector screws into on the head. It's held down by a splined ring collar.

Thanks.

Movies at
http://www.pauldrayton.com/uploadfiles/merc/nailing/nailing.html
Thanks