Sixto,

I've been watching intently, but quietly. I think I am in the same situation. My car has gone from using / leaking a quart every 2500 miles to a quart every 300 over the past year. I had a few leaks fixed by a good independent hoping that was the issue. It wasn't. The mechanic really cleaned the engine to see where the oil was going. He showed me a leak right at the head/ block joint in front of #1 exhaust. That would match your pictures.

The MB stealership did a quick look and their next step was remove head and measure piston height, to the tune of $2000. I passed and called Noels. For $8000 ( $6500 long block and $1500 installation) I could be cooking again. I was considering making reservations and literally was looking at flight costs from FL back to NC. Then the next week my ignition switch started giving me a fit, and the stealership quoted $1000 to fix that. That was it for me.

Forgive for I have sinned. I had no time to mess with it and debated the financial wisdom of investing in an engine and ignition fix. I bought an Infiniti I-35 for a song and have been driving that since July as my primary car. I expect it will be my daughters car in a year or so when she starts driving.

The Mercedes still runs wonderfully, even at a quart per 300 miles. Not many flying bugs in the area lately.... 8). I drive it occassionally to keep all the parts working. I hadn't driven it more than around the block in the past 3 months. I had to make a 30 mile trip and back the other day so I decided to take it. Along with following Sixto's inspiration and ambition fixing all his issues, I fell in love again driving it. There is no comparison to the small Infiniti and I miss the diesel clatter. It is time to fix it once I can save a few $. Well more than a few...

So I am at the same decision points as Sixto... new 3.5 longblock? Find a 3.0 to drop in? I did locate a place that has 3.5 sleeves for $35 a piece. But that is probably past my skill level. An engine / head swap, sure I could do that.

Sixto, if you get the 3.0 into the 300SD and it works, that might be my preference. My 87 SDL had nearly 300K on it and was still running well. I can live with a little less performance for the longevity.

FYI.. in discussion with Noel, he thinks the issue is glow plug failure causing hydrolock. To me it looks like it may be headgasket / oil leak leading to hydrolock.

And then I still need to fix the ignition lock.. 8(
Chuck