Is my engine dead if I drove overheated for few miles
I own 99 323I, it has 150k on it, I just love driving it. Last Friday morning, I saw the coolant indicator but drove it work with a plan to have the coolant filled near work (40 miles from home). One the way back home the coolant indicator disappeared, so I thought the indicator popped in the morning coz I took out the car after a week or so that too in the cold temp. So kept driving, the indicator popped on and off, suddenly saw the heat indicator on the extreme red, slowed down but kept driving (ignorance and stupidity) the indicator still on the right but not bright red. I may have driven for 5 miles with the heat indicator at its peak and finally car stopped. Got the car towed it to workshop, coolant tank cracked and they did compression and leak-down test. the results from leak down test are 1-10%, 2-15%, 3-18%, 4-25%, 5-15% and 6-5%. Do these results show that engine is no more good shape. Mechanic is suggesting to go for a different engine (lot of money though). based on what I read in forums leak downs around 20 are still Ok. but not sure, I am thinking of getting the coolant done and see what happens. What do you experts suggest.
Thanks in Advance