ok, so if the car is first started in the morning then the head is cracked?
 

I have a very simple question regarding my '87 300SDL. Everyone says, when the engine is cold, check the upper hose. However, should the car be running? I would think the car would have to be running for the test since it would then be that it would generate pressure that could pressurize the system.

Thanks
David

The engine remains shut off.

You are checking to see if the engine has pressurized the cooling system via a leak between the combustion chambers and the cooling system. This will show up the next morning.

The hose will be very hard and you won't be able to squeeze it together with two fingers.

Then open the cap on the expansion tank. You will hear a blast of air escape if this is the situation.

Now squeeze the hose again. If it is now soft and you can squeeze it together with two fingers.................well................. :eek:

I think what Brian meant to say was, "If that's the case, you are screwed"

Aaron, see that face at the end of the dots in my aforementioned post. That's the face of a man who is getting screwed and can't figure out why he is not liking it. :D