How many hours of labor to replace engine bearingsin 500E?

[tom woolner]

Last fall I spent close to $11,000 on my 500E motor - timing chain, upper and lower rails, throttle actuator, all hoses, etc. When it was all put together, there was no oil pressure. Apparently ther was a bent oil filter housing. Taken apart, fixed, put back together.
Recently, I heard a chain rattle. While having a/c compressor replaced, my tech replaced the chain tensioner.

A week later, I heard a clanking sound when starting the motor (not the first time started that day - engine was warm). Since then, I have heard intermittantly when starting the engine a noise that seems to be a timing chain rattle.
My tech does not want to takethe engine apart until the symptoms become more consistant, i.e., we can reproduce the sound in his shop. QAmong the possiblities he mentioned were the engine bearings (there were signs that the engine had been taken apart prior to doing the timing chain. I bought the car with 96,000 miles; it now has 155,000.

I'm a bit freaked - I've spent $17,000 miles over the last year, and have
replaced virtually everything that can be replaced, including the transmission two months ago, A/c work done last month. I have little or no more $$ to put into my beast.

If it is in fact the bearings, what am I looking at, labor and part-wise?

Tom