On Feb 10, 10:19 am, "Randy E Schaben" > wrote:
>
> My brother had his head gasket repaired on his '98 Monte Carlo 3.1 V6 (POS)
> as the oil had a milky look to it. After repair the milky oil returned.
> Now mech. says block may be cracked.
> Question: Should the mechanic been able to know the difference between bad
> head gasket and cracked block?
>

I'm going to comment on this because I've done some work on the 3.1
and 3.4 GM engines and this was when I was a Ford tech. Go figure.
It would be hard for the tech to find the cracked block when just
replacing the head gaskets or the cracked heads, especially if there
was a visible fault from the head gaskets or the heads. Also, the tech
really wouldn't know the history of the car. Did the oil just start
getting milky or did the driver run the engine hot for a half hour?
Remember too, that to do a thorough job of finding the cracks the
block should be checked by a machine shop, impossible to do with the
block in the car.

Whatever the problem now, the dealer now just wants to replace
everything to make sure the problem goes away. You will probably find
the the dealer's estimate will be more than what the car is worth.