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Greetings-
After purchasing this 1982 300 series, I did a lot of maintenance, including removing the crank pulley to replace the front crank seal. 3000 miles later, some noises alerted me to discover that two of the six bolts connecting the crank pulley to the crank "mounting plate"(?) had backed out and the other four bolts had sheared. I honestly can't say that I used any threadlock when installing the bolts. Is the issue as simple as, due to not using threadlock, two bolts backed out, destabilized the connection of the pulley to the plate, eventually causing the other four to shear? I'm about to begin the repair process, and just want to make sure that there isn't an additional potential cause I should be aware of. The plates connection to the crank appears firm. Many thanks.
From my experience the thread locker is usually on the bolts when you buy them, if thread locker is required. I dont have much experience with early model MB's though.
I think I have the correct directions im looking thru.
Looked up the part #'s for the bolts and it doesnt show then with thread locker. Just the bolt.
The manual notes washers on each of the bolts. The only mention of a lubricant is on the large bolt..
Thanks for the detailed reply!! I've done additional research and it sounds like my experience is not uncommon. Unfortunately, I'm going to have to pull the harmonic balancer in order to more easily extract the sheared bolts. I'll source new crank pulley bolts with a higher shear strength rating and install with thread locker and proper torque. The research leads me to conclude that, based on the experience of others, no additional factors were at play in causing this to happen in the first place, so I feel I can proceed with the repair with reasonable confidence. Many thanks!
