187119 Lock Washer Finish

[Ed S.]

What is the "correct" finish for the lock washer # 187119, in my case used with the six bolts that secure the fan shroud to the radiator supports on a '64.

64 Judging Guide states bolts are zinc, lock washers are black phosphorous but....there are several references in Forum threads to this lock washer, two members state they should be zinc, two say black phosphorous.

One popular vendor includes zinc washers with a set of bolts for this application, another popular vendor includes what appears to be a black ph. washer.

AMK fasteners and hardware carries the 187119 lock washer - available in zinc or black ph.

In a situation like this is it just prudent to go with the Judging Guide - even though there is evidence that the finish might be different that what is cited in the manual?

[Alan D.]

Re: 187119 Lock Washer Finish

Go with the JG (assume it wants zinc), if it's declared wrong later - simple to change. Remember the bolts used to retain the shroud are listed in the AIM by part number. Those are zinc with a flat head, however there is lots of original cars out there which have black pointed bolts!
As for the zinc question, see GM document!

[Ed S.]

Re: 187119 Lock Washer Finish

Thanks Alan. That is the kind of info I was looking for. I have my answer.