It doesn't actually mean anything, it is just a marking.
Markings mean nothing on a GSD's head.
If you mean a bolt with a head size of 24mm (M16) then the recommended torque setting will be 210Nm but if you mean a head size of 36mm (M24) then the recommended setting will be 710Nm.
assuming you mean with the engine intact-code on side of block, code inside glovebox of original vehicle the engine came from.original crank pully will have a marking on it meaning 4 bolt main. not sure what the marking is but its different between 2 and 4 bolt mains.if you mean looking at the block with the heads off the caps holding down the crank have 4 bolts to hold each cap, a 2 bolt main has well...2.
George Dunne invented the marking gauge with his giant head
It's a measure of the strength of the bolt. The strength is measured using what's called a grade. In this case, you have a grade 8 bolt. The higher the number, the stronger the bolt.
bolt strength markings. Numbers represent metric threads and slashes represent standard threads (the greater the number/slashes, the greater the strength of the bolt.
It has a 36mm head and is 7.5 inches long.
You can over-torque a bolt and you may not know it. But you can damage the bolt in several ways that may be visible. 1. The threads will be stripped or sheared away. 2. The bolt will be permanently stretched so it is longer than it originally was. 3. The head of the bolt may be twisted or the corners of the bolt head rounded off. High strength bolts are marked on the head with symbols that indicate the strength of the bolt. You should know what type bolt you are using and its application. Just because it is made of Steel, that does not mean it will have sufficient strength for some applications.
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