stainless or standard steel

[alan griffiths]

can I use s\s bolts with my solid mounts or will the standard
merc mounting bolts be stronger. (70 merc )

[Techno]

I don't know what the standard merc bolts are or for that matter what the SS grade you would choose. Mcmaster carr lists the bolt strengths and the strengths for SS bolts so you can choose for yourself. The different sae grades and like B-7. SS would be 304 or 18-8- generic SS and some of the bolts specify something different- SS

Just remember a 1/2" bolt ain't 1 square inch so the actual strength is much lower- for any of them. Its a good comparision though.

[Gordie Miller]

from Mercury are stainless steel, they supply them with all new motors including V-6's. You may choose to use something else but that is what Merc furnishes as OEM. SS is generally equivalent to Grade 2, although I'm not positive if the Merc SS bolts are that or not, it is expensive to manufacture a SS bolt of higher strength, so I suspect the Merc OEM bolts would fall into this category.

[alan griffiths]

I was told by a bolt spesilist yesterday that a 304 ss was about
a grade 5 and the the higher the grade ss the lower the tensile
strength ei 316ss is weeker than 304 ss
is this correct

[Gordie Miller]

the 300 series, i.e., 304 vs. 316 is corrosion resistance, little or nothing to do with strength.

[alan griffiths]

yes however to make them more corrosion resistant
they are supose to get weeker in tensile strenth.
I just spoke to another bolt person that just emailed me
he said the same thing and also that a304 was about
a grade5 and in tensile strenth off about 8 ,ie in between
mid steel and high tensile steel .
so I think I will just use them and check them regularly.

[Gordie Miller]

He is pretty up to speed on this stuff. If you have a McMaster Carr book, #109, go to page 2944 it tells the difference between some of the various grades of stainless. In laymans terms they fall between gr 2 and gr 5. Be sure to take precautions against galling.

[alan griffiths]

Thanks Mate