I've been contemplating work on my daughter's '87 300E with 270,000 mi. and read this post with interest.... comments...

With "only* 144k (IF serviced properly!) the bottom end should be in fine shape. My compression was almost perfect down the line.

Since you have the drive train already out...

Bottom end: Rings and bearings should be fine (see above). Go ahead and replace the crank seals and possibly the timing chain, tensioner and guides.

Head: Clean, check. Valves and seats should only need a "touch up". Go ahead and replace valve guides (a weak point) and, of course, seals.

Also, this would be a good time to replace water pump if not done recently (hard to get to assembled / in car).

If you had oil getting into coolant, this is a common problem. It wouldn't have effected compression. There are oil and coolant passages from the block to head near #5 that are in close proximity to each other. The leak is between the two. You should see that when you pull the head.

Trans: No leaks?? Gotta be kidding!! At the very least, while it's out replace all the seals at the front near the pump. If it is not leaking now, it will soon!! The trans must be pulled to fix this common leak area. It would also be a good idea to replace all the external trans seals at this time if you don't want to go into it internally.

Unless the car hasn't had proper maintenance or other problems are present, the above should get you in great condition for some time with minimal cost and time.

Further comments anyone?? I'd be interested in experienced opinions since I'm contemplating a similar venture this spring, mainly head and trans rebuild.