603 prechamber collar - PeachParts Mercedes-Benz Forum

dieselbenz1 · #1 03-13-2018, 09:20 AM

I'm just trying to determine the differences betweem 617 prechamber collar nuts and the early 603 collar nuts. As for the prechamber shims on the 603 is it possible to use 617 seal rings as they come in greater thicknesses. I'm just trying to line up options and understand differences at this point.

Diseasel300 · #2 03-13-2018, 10:10 AM

The 617 used sealing rings, the 603 does not. The "rings" on the 603 are shims, not seals. The shim is there to adjust the height that the nozzle sticks down in the cylinder, too low and *crunch* when the piston comes up.

dieselbenz1 · #3 03-13-2018, 10:21 AM

But the 617 seal rings also come in varous thicknesses to adjust the prechamber tip. The 603 shims are available in .3 , .6 and 1mm. While the 617 start at 2mm and go thicker. If i needed to space 2.3 mm that would be 1 617 seal vs 3 603 shims.

Diseasel300 · #4 03-13-2018, 10:52 AM

If you need to space that far you have bigger fish to fry. The head is designed differently on the 617 and 603. The 603 uses a shim, if needed. The 617 requires a ring to seal the chamber to the head. Different design philosophies.

Diesel911 · #5 03-13-2018, 12:01 PM

Quote:

Originally Posted by dieselbenz1

I'm just trying to determine the differences betweem 617 prechamber collar nuts and the early 603 collar nuts. As for the prechamber shims on the 603 is it possible to use 617 seal rings as they come in greater thicknesses. I'm just trying to line up options and understand differences at this point.

I have only removed the pre-chamber collars from one Aluminum Cylinder Head. I don't remember what Engine it was. However, the collars for the Aluminum Head had a wider threaded area then the 617.952 does.

My subjective opinion of the pre-chambers on the Engine with the Aluminum head was they were smaller in diameter and length. But, I cannot guarantee that is true.

If the 617 prechamber seals were of the same inside diameter one would think that one of them would have the same part number as the seal for the newer Engines.

dieselbenz1 · #6 03-13-2018, 12:21 PM

I was thinking the 603 collar has a wider threaded length from some pictures. Those slotted collars for 603 are scarce little buggers.

Seal rings 617 and the shims 603 do have different part numbers but I seem to recall reading somewhere where they were the same size.