Let's start here:
That makes no sense. Why would a server restart cause an update on every row of your table?
but that does not work because every time the server restarts it also updates the datestamp.
There is something very important in there that you aren't telling us.
And this makes little sense to me:
In order for that query to delete anything, you would have to have a SINGLE RECORD where the value of Hitpoints looked something like this:
DELETE FROM object_data
WHERE Hitpoints LIKE '%wheel_1_1_steering",1%'
AND Hitpoints LIKE '%wheel_1_2_steering",1%'
AND Hitpoints LIKE '%wheel_2_1_steering",1%'
AND Hitpoints LIKE '%wheel_2_2_steering",1%';
Joe said "wheel_1_1_steering",1 time, and then Bob said "wheel_1_2_steering",1 time,
and then Harry said "wheel_2_1_steering",1 time, and Anne said "wheel_2_2_steering",1 time, as well.
My gut feeling here is that you have a badly designed database. But it's pretty hard to tell.