Here are the details surrounding this car..
The car had been running great with the exception that it had been running a
bit hotter than usual since the beginning of the hot weather. (I had the
thermostat changed and the antifreeze flushed last fall so that sort of
surprised me). I was coming home one recent Sunday night and the car
overheated - got very dangerously hot - The engine turned off on its own and
all the antifreeze and half of the oil drained from the car. I had it towed
home. I recently worked up enough nerve to look under the hood.
It seems the water pump is shot. Not the end of the world.
I checked the oil and it was low but clean - no sign of antifreeze in the
There is a sensor up high on the left side of the block (by the fuel
injector pump) that blew out.
The wire and connector tip need repair and a new sensor.
When the sensor blew it must have knocked out a spring on or near the fuel
pump on the motor side...can't locate the spring but I have a second 300SDL
as a reference point and can see how the spring connects to the linkage
I filled the liquids and tried to start but she won't turn over.(I was
conservative in my efforts to not risk further damage).The antifreeze
immediately started leaking from the water pump.
The transmission fluid looks and smells ok.
My questions: Would a faulty water pump cause the extreme temp problems I
experienced? The 300SDL has a sensitive head - what's the chances that It's
cooked, warped, etc? How can I check the status of the head and block
without ripping it apart? The radiator looks new-how do these radiators
respond to high temp shock treatment?
Concerns: I can't start the car. What's the chances that I put all of this
work into it and it still won't start? Motor has 305K on it. When I got
the car the coolant reservoir was cracked and had it replaced after
unsuccessfully repairing it-a possible sign of previous overheating
problems? I can manage the water pump install, sensor install, and
replacing the thermostat and fluids but have little idea where to begin with
the head job. If I go the rebuild route, I'd like to have some level of
comfort that I can make the investment and the engine will be corrected
without any "major" repairs necessary for a while.
As always, your help and advice is always greatly appreciated.