I accidentally had a piece of my screw driver fall into block heater hole while I was taking out the freeze plug? Any thoughts? Can I flush it out? Tried magnet can't find it? Will this harm my engine? Your help is appreciated.
Would not believe any harm can happen as it is in the water jacket area and only water/coolant flows there, mind you if it were to block a very tight water passage area then a 'hot spot' could occur.
Personally I would not worry.
The only thing your magnet will find is the engine block and ignore the bit.
I
A long shot but it might be worth while to take a look with a small inspection mirror/flashlight and or try a set of mechanical fingers.
I wouldn't think the velocity of the coolant in the lower block will be high enough to lift it up anywhere disastrous.