300E thermostat housing bolts Home Depot!
 

replaced NOS Wahler stat with no breathing hole with new Wahler with breathing hole.
Noticed that one of the bolts is crooked.Tried reinstalling /broke.
Went to Markham Mercedes,ordered 3 bolts.they call it screws (part # 163-990-05-04) supposed ly superseded parts.
Went back next day.The bolts came with big non-removable washer and not the same as the original.Wont fit.Parts guy scratched his head and say he'll find out more.
Meanwhile no car for 2 days.Went to Home Depot got a M6-20 or 25 bolt for 40 cents (part # 128436 for bolt and 128556 for washer).Fits.Car again.
Asked MB parts guy to stop looking(he still have not found one that fits) and got 7 bucks refund(for 3 bolts)

I don't see any problem short term, but long term if the bolts are not as high quality as factory (doubtful) then they will corrode more and possibly cause trouble. If I coudn't find the right bolt from the dealer (What????) then I would probably go for some stainless if I could find that.

Tom W

yea... did you buy stainless steel bolts or regular steel. Either way galvanic corrosion is going to cause some nasty issues if you didn't use some anti seize on the threads

no stainless
 

Stainless and aluminum really don't get along; creates more corrosion in the aluminum hole, making it difficult to remove the bolt later on. Ask any sailor/rigger.

The MB bolt and the new Home Depot bolt are both marked 8.8 which I assume is a measurement of steel strength or thickness? can some metal specialist verify?

All the MB bolts are tarnished dark grey (and obviously one broke)I dont think they are Stainless steel.

8.8 is the strength. That should be fine.

Tom W

Congratulations on now having some Chinese bolts on your car.

Danke