I paid a local mechanic (I'm in California) $4400 to do a valve job on an
'89 Mercedes 560 (V-8, overhead cam), during which he removed the heads
reassembled them, replacing the entire valve train. 900 miles later, the
cams froze up. He accepts no responsibility because there is sludge in the
(not previously removed) oil pan, which may have caused the oil pump to
up. I don't know if the oil pump plugged up or not (there was pressure on
the indicator when I stopped the car), but I figured that with sludge on
bottom end (the chunks are approx. 1/4" thick in the pan) that there would
be sludge on the top as well. Other mechanics here have told me that they
always see sludge in the top when there is sludge in the bottom.
My question is should the mechanic have noticed the sludge and take responsibility for the damage?
Will indicators of sludge be present in the top end of an affected engine
When an engine has a lot of sludge buildup, pulling the pan is a prudent thing to do before reassembling the engine. And yes sludge would be visible when he took the valve covers off the engine.
He is correct that he is not at fault technically; he is at fault for not covering his butt and now losing a good customer!
If he pulled the pan there is no guarantee that this problem would have not
happened. He would have at least done the best job possible.
When an engine is opened up for repairs the sludge/carbon dries up, breaking
off and clogging the oil pump pick up tube as then engine runs.
He could have taken the car to a shop that "flushes" the oil using a special
machine. This machine is just starting to gather support in the automotive
industry. You can read about this machine by going to the websitewww.motorvac.com this site will explain how it gets rid of "sludge" in an engine.
I know this is a little late to know after the damage is done. Just realize
that in the future this can be avoided.
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