gawlbpd,

As leathermang noted the cost depends on the damage and how much you do. It is reasonable for you to bracket the costs by assuming a condition with lesser damage and another with more damage, needing more parts. After the chore of head removal and partial dissassembly is complete, a shop will do the rest, and putting it back together with old or new parts is about the same cost. So, make some assumptions and do the math.

You can get prices from Fastlane (click on the Fastlane tab at the top of the screen, then click on the request for the on-line catalog and the rest is obvious) for these parts, then assume a machine shop will be around $250 to $300 for just disassembly, measurement/inspection/testing, minor machining tasks (removing/pressing new valve guides and possibly seats in, assembly, and putting up with your questions about condition of parts, etc).

The parts to buy as a minimum will be a head gasket package/kit, valve stem seals, valve guides and possibly a valve or two, and also possibly a valve seat or two. I did this a long time ago on a 220D and the cost was very low as most of the trouble was leaking valve stem seals, which left thick deposits of carbonized engine oil on the valve stems and upper poppet surfaces, which ended up interfering with valve operation. All the valves cleaned up, the springs tested ok, and I had one cracked valve seating ring in the head. This was machined out and a new one was pressed in, the head was skim cut, Magnetic Particle tested for cracks, pressure tested and then it was all put back together for a whopping $123. The parts I bought (gasket kit, seals, guides, chain tensioner rails, various bits and pieces like pins, nuts bolts and washers) were about another $100. I bought some sockets for injector removal and installation, and a few other nice to have tools for another $50 to $75. I did not buy tools like prechamber pullers/installers or any other very specialized MB tools. I let the shop handle those chores as they had done it before and already had the tools. This was a while ago, so the costs have probably escalated by a factor of two. And you have at least one more cylinder.

On the high side assume you will replace all the valves, and the prechambers. If it costs more than that the shop is gouging you or your head is not worth repairing. In this case check another shop and research costs of rebuilt, or rebuildable heads.

But, make sure the problem is in the head. If it is in the cylinder to piston interface, fixing problems in the head is not of any value, overall. Good luck, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)