Guru
Joined: 15/07/2006
Location: AustraliaPosts: 640
| Posted: 09:23am 24 Oct 2023 |
Pete, I had found that chart a few days ago. And I did some calculations. But here I will type it out. My scrawl on the paper will be hard to follow.
There is 18 of those little M5 bolts. 316 Stainless steel. That's the factory bolts.
Cross section area of all 18 of them, 353mm2
353mm2 x 700N/mm2 = 247450Nm
The 5 stud bolts they have are M12, 10.9 high tensile.
Cross section area of all 5, 565mm2
565mm2 x 1035N/mm2 = 585355Nm
So you can see straight away that the small M5 bolt strength is not matched. However they do have leverage (greater circle diameter) compared to the the 5 stud bolts.
But with all the possibilities, still the question arises, why the left motor and not the right motor?
Wheel nuts are tapered. This helps to align but also stops the rim from slop on the stud bolts. I thought maybe if my Brake and auto friend and Pete suggested, hardened dowel pegs, maybe the bolts should be tapered. Countersink.
I have drilled and tapped to M6
calculating....
18 x M6 bolts cross section area, 509mm2. 316 stainless steel
509mm2 x 700mm = 2356303Nm
That is still not up to the 5 x M12 strength, but better than is was. I don't think I have enough room to drill and tap 8mm. And I am hoping that the extra leverage will make it enough not to break them.
Anti seize is not a good idea. I can't have them coming loose.
I have assembled the motor with the M6 countersink 316 stainless steel bolts and the suggested Locktite 515, as a sealing gasket and on the threads. I sure hope I can get it apart if need be, some time later. I have also added 3 threaded holes to use with jacking bolts to separate this plate off which should make future dismantle easier.
Thanks everyone for your ideas.