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I have never seen loctite recommended for any kind of rod bolt. It won't do any good anyway as the rod will get real hot, hot enough to melt steel, if there is a problem, like lack of oil and the loctite will give out immediately or if over revved the bolt will break. The loctite is of no real use as far as I can tell.
Here is how it is described in many books, on cars and on fasteners. The bolt is like a spring. It is tightened up and stretches, like a spring. It is that spring tension that holds things together, therefore there is no need for any locking devices.
The bolt will fail if its ultimate strength is exceeded or if the spring tension is exceeded and the bolt undergos a couple of hundred cycles that exceed the initial torqued tension.
There are three tightening methods.
1. Torque only- This depends on using a lubricant, such as oil. To get the correct value one must use exactly the lube recommended by the factory. The drawback to using torque is that the amount of tightness or stretch that the bolt sees can vary by huge amounts, like 50% or more. And worse yet is each time the bolt is tightened the threads are burnished and less and less torque is needed to achieve the same degree of tightness.
2. Torque and stretch. This method is much more accurate than just torque. The bolt is tightened to a low value of torque, and then turned a specified angle, eg 85 degrees. This results in a much more repeatable ammount of tightness than torque alone. These bolts are typically only used a single time. These are called Torque to yield bolts. The bolt retains some permanent stretch when it is used.
3. Stretch only. This is the best method and most repeatable. This is the one used by Carillo which uses the worlds ultimate bolts made by S.P.S. (at about $25 ea) and ARP. A U shaped dial indicator is placed on the bolt to measure its length and the length is monitored while tightening the bolt. When the bolt is some number, e.g. 0.006" longer it is considered tight. Again a lube is used, but it doesn't matter much what it is as it will not affect the result. Some of these bolts can be reused.
Here is how it is described in many books, on cars and on fasteners. The bolt is like a spring. It is tightened up and stretches, like a spring. It is that spring tension that holds things together, therefore there is no need for any locking devices.
The bolt will fail if its ultimate strength is exceeded or if the spring tension is exceeded and the bolt undergos a couple of hundred cycles that exceed the initial torqued tension.
There are three tightening methods.
1. Torque only- This depends on using a lubricant, such as oil. To get the correct value one must use exactly the lube recommended by the factory. The drawback to using torque is that the amount of tightness or stretch that the bolt sees can vary by huge amounts, like 50% or more. And worse yet is each time the bolt is tightened the threads are burnished and less and less torque is needed to achieve the same degree of tightness.
2. Torque and stretch. This method is much more accurate than just torque. The bolt is tightened to a low value of torque, and then turned a specified angle, eg 85 degrees. This results in a much more repeatable ammount of tightness than torque alone. These bolts are typically only used a single time. These are called Torque to yield bolts. The bolt retains some permanent stretch when it is used.
3. Stretch only. This is the best method and most repeatable. This is the one used by Carillo which uses the worlds ultimate bolts made by S.P.S. (at about $25 ea) and ARP. A U shaped dial indicator is placed on the bolt to measure its length and the length is monitored while tightening the bolt. When the bolt is some number, e.g. 0.006" longer it is considered tight. Again a lube is used, but it doesn't matter much what it is as it will not affect the result. Some of these bolts can be reused.
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