The head gasket job on an M104 isn't the worst in the world. Inline engines are pretty easy to work on. There is a good write-up on the job here:
PeachPartsWiki: Head Gasket Replacement
The thing to worry about with the head gasket job is actually the wiring harnes. If you have one of the brittle harnesses, with the insulation falling apart, you might just wreck the harness when you remove it to do the head gasket job. I think a harness will cost you something like $900, just for the part.
Any 15 year old car you are going to buy is going to have issues, including engine wear. If you're a handy guy with the wrenches, then a head gasket is only going to cost you some minor parts and then your own time. That's not a lot of investment. A wiring harness is a major investment, especially considering that car isnt' worth any more than $4-5K if it was perfect.
My advice would be to have a PPI done by a qualified MB specialist. Find out what other hidden expenses await you (like the lower control arm bushings, for example) and have them try and verify the condition of the wiring harness. If everything else is good, you might be able to pick up a good deal and only have to invest a few hundred dollars plus your time to do the head gasket.
PeachPartsWiki: Head Gasket Replacement
The thing to worry about with the head gasket job is actually the wiring harnes. If you have one of the brittle harnesses, with the insulation falling apart, you might just wreck the harness when you remove it to do the head gasket job. I think a harness will cost you something like $900, just for the part.
Any 15 year old car you are going to buy is going to have issues, including engine wear. If you're a handy guy with the wrenches, then a head gasket is only going to cost you some minor parts and then your own time. That's not a lot of investment. A wiring harness is a major investment, especially considering that car isnt' worth any more than $4-5K if it was perfect.
My advice would be to have a PPI done by a qualified MB specialist. Find out what other hidden expenses await you (like the lower control arm bushings, for example) and have them try and verify the condition of the wiring harness. If everything else is good, you might be able to pick up a good deal and only have to invest a few hundred dollars plus your time to do the head gasket.
