Fan bolts - cheap fix

[BillGrissom]

As many others, I rounded off one of the 4 special bolts that attach the fan clutch to the water pump. I then read that I should have ground down a box wrench to slip in the very narrow space. I did so, but didn't want to re-install the rounded bolt and risk not getting it off, like if an emergency repair (I got it off w/ vise grips). I have seen used bolts on ebay for a high price (for bolts), but I am cheap and try to be clever.

I thought "stupid design", since the head is too small for an open-ended wrench and no room for a regular box wrench. I am allowed to fault M-B designers because I have an M.S. in Mech Engr. The cheap way out is to buy 4 M8 bolts w/ 1.25 mm pitch, 16 mm long, with "JIS reduced head". These are Ace Hardware item 44518 in the pull-out trays ($0.84 ea). The hex head is 12 mm vs 13 mm for standard bolts. Initially, I got standard ones and while you can get them in, the head drags on the fan clutch slightly (might depend on yours). The smaller head fits and is big enough that I have no concerns using an open-ended wrench. I coated the threads w/ anti-sieze so no more rounding off problems.