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.

Thanks for the heads up, good info Bill.

Just for the record, 114-990-00-10 is the MB part #. pricy little buggers at around $7.00 ea. So ACE Hardware is a good back up in an emergency.

Another bolt that is a PITA is the lower Shock Bolts on the 123. I use the same ground 10mm on both. wonder if they are the same bolt?

Thinking about it a bit, Seems the Shock bolt might have a wider area under the head, just don`t have any loose one`s to compare.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works