Depends on why that one came loose. If someone had it apart and forgot to tighten that one, I'd live with it. If they forgot to tighten all of them, I'd expect to hear a rattling / banging-type of noise.
If more come loose, eventually the last one or two might shear off from carrying all the load, at which point you gotta pull it apart. If you are afraid it's going to come apart and leave you with a piece of bolt broken off inside the hole in the crankshaft, then you're guaranteed of having to take it apart. I'd be inclined to take my chances and keep on driving. Check inside the inspection cover in a month or two to see if any more bolt parts show up.
Sunday, July 8th, 2012 AT 11:14 PM