What is this? Bracket/screw near harmonic balancer
 

87 300D ... OK, was investigating my engine last night in the wee hours, and noticed a bracket and screw that I can't figure out the purpose of. On the passenger side, front of the engine, sort of right above the harmonic balancer and below the fan pulley, there's this bracket with a bolt sticking through it, just sort of sitting there. The bracket seems to be attached to the crankcase, but it's kind of loose, and the bolt attaches to nothing. Neither pulley makes contact with it, but it's pretty tight in there. I'm stumped: what is that? Is it supposed to be there?

Edit to add: I searched the EPC and didn't see an item that looks like it anywhere.

on a 617 it sounds like the tach sensor, not sure about your engine

Is this the one that has very little clearance from the belt and has a small point on it?

That bracket with the threaded rod projecting upwards, has two purposes one is used to establish the accurate position of the timing indicator(arrow) by inserting a tool into that position with the #1 piston at TDC and then adjusting the timing indicator to read correctly the marks on the balancer, the tool interfaces with the pin which is on the balancer, that is how it is used in the static mode. The second use of that bracket is after confirming its' accurate positioning there is a sensor which is installed into that position which is used along with other electronic components to moniter and display the Start Of Delivery timing with the engine running, the sensor uses "Hall Effect" to register the pin on the balancer as it rotates past, in the dynamic mode.

It should not be "loose" but it is just a stamped bracket and the part you see is out at it's end so if you pull or push on it it will flex and movment will occur.

P. S. The part number is # 603 150 00 73 , it's listed in the EPC under the Major assembly M-engine section, 15 Electrical Equipment, 105 Attachment Parts, part number #263

Sounds like it's the combination timing pointer and attachment hoop for the factory diagnostic rpm tool.

Sixto
87 300D

Thanks very much guys, that sounds like what I'm looking at. I learn something new every day.:)