87 Accord-Engine Overheated
 

About 2 weeks ago, my 87 DX Accord engine (240,000 mi) severely overheated (temp
gauge red-lined) and the engine stopped. Car sat at the curb over night. Had the car
towed to a local garage the next morning. When they went to look at it they noted:
1. The car started right up (and even called me to ask why did I bring the car into
their shop)
2. Added 1 gallon on water to the radiator.
3. Did a pressure check on the cooling system and saw no indication of leaks.

They said due to the overheating, the compression on the engine is probably worse, so
gas mileage will be less.

I've changed the oil and filter.

But, in the intervening 2 weeks, here's what I noticed:
1. Gas mileage seems to have gone from about 25 to 34 mpg.
2. The values (which previously rattled because they were loose), now are totally
silent.
3. The engine runs smoothly and quietly, even uphill, under load.

So, is the surprising improvement only temporary and the engine will totally die in
the not-too-distant future, or have I someone managed to overheat the engine enough
to compensate for 240,000 miles of wear but not damage it, as it nor seems to run
almost as new????

I love the car and thought I had destroyed it, but now I wonder and ask you for your
sage advice / opinions.

Thanks!
Ken