The $35 torque wrench that started a fire near Tulsa
Picked up a used torque wrench at a swap meet for 35 bucks, figured it was good enough for my 87 Civic. First time torquing down a head bolt, it clicked early on cylinder 2, and I thought nothing of it. That evening I smelled something burning, popped the hood, and coolant was spraying onto the exhaust manifold from a warped head. Cheap wrench cost me a junkyard engine swap at Pull-A-Part, so now I test any used torque tool against a known bolt before trusting it. Anyone else had a bad tool mess up a build worse than the part itself?
Read an article once where a guy tested a bunch of old torque wrenches from garage sales and almost all of them were way off, some by like 20 percent. Yours clicking early sounds exactly like that, the spring inside just gets tired or gummed up after years of sitting around. A warped head is brutal too, that's not a quick fix at all. Good on you for testing them now, I always borrow my buddy's digital one since he keeps it calibrated. Cheap tools are fine for some stuff, but not for engine bolts that need to be exact.