OM603 head
 

I have a 1987 300D and just had a head job done the head casting numbers are 20. I put everything together and fired it up dosent run right sounds like I'm having a fuel problem. Now I forgot to put these in could this be my problem? How do I install them first 3 face down or second face up? What about the rings? http://img.auctiva.com/imgdata/5/0/5...68898867_o.jpg

The bottom 6 are the injector heat shields, and they go face up like the right 3, under each injector. Yes not having them will cause trouble. They must be replaced each time you pull the injectors.

I don't know about the top 5 washers.

Thanks I still would like to know what the other rings are I think I had six with the gasket kit but not sure six or five?

The thin rings are possibly the seals for the prechambers..........only necessary if you have removed and replaced the prechambers.

That is exactly what they are for. Based on how much head work was done (machining) to insure that it is flat these rings are available in various thicknesses to insure that the injectors extend into the cylinder head by a specified amount.

I wondered about the Pre-chamber Seal Rings and their different sizes when I read them in the Manual. You are supposed to measure the Pre-chamber protrusion and use the different sized seals to adjust that protrusion.
When you change the Pre-chamber Seal Rings while the head is still on the engine how do you guess what size of Pre-chamber Seal Rings to use? I am assuming that the old one gets crushed some to seal so measuring the old one may not help much.

You can measure the thickness from the top while the head is still on by a measurement of how much aluminum you remove (subtracting heights on a dial guage) using the precombustion chamber countersinking tool. The factory shop manual mentions nothing about the washers being crushed, and mentions changing them only when you remove aluminum when refinishing the sealing surface.

If your head hasn't been countersunk in this area, it probably has no rings under the prechambers, since they are not needed as "seal rings", they are mainly spacers to maintain the 7.6-8.1mm projection of the tips. So if you don't remove material from the head, don't change the rings.

Thanks!