If you could be more specific, identify and describe sounds other than the clatter, which is generally from injectors, but there are other sounds the 603 makes that should be considered warning sounds such as a worn belt tensioner...tick tick tack tick tack tick bang tack, or possibly hydraulic lifters which typically sound and they do change their tap tap sound at idle....and then there are the injectors! They sound out as though you were pounding a 6 penny nail into a piece of oak, the trouble is, which one? To find out if this is the case, just add either Power Services diesel cetane additive to your tank, or better, Redline...bought at most Pepboys, or AutoZone, or franchised auto parts stores, don't think Walmart sells that. Otherwise run the engine and back off each injector tube nut atop each injector and if the nail nail saound stops, you've found the noise maker!

Hydraulic lifters will eventually become noisy, and for the 603, they will survive without too much efficiency loss......However, I have found that a worn cam can make healthy lifters make noise!

Many people here think the lifters are faulty when they start to rap, or tap, but a measure of the cam lobes may reveal excessive wear and a new cam, about $275 will make old lifters think their young!

I use it to burn carbon from chambers and back side of valves, works very well. Nothing aside from oil goes into my crank case...

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I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

That is very odd. The 603 in proper tune is usually much quieter and has a different tone to it, than the 617.

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair

Yeah a 603 should sound pretty much like a gas engine at anything above idle.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I'll try to figure out this camera as it records sounds somehow.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]