Rear Engine Iso Mounting Stud

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olympus

olympus

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Hi there & a Happy New Year to one and all:)
just about to mount in the Eng./Gearbox cradle and i note that the threaded section on the end of the rear mounting stud is greater on one end than the other??
Is there a specific way the stud needs to be installed??

Many thanks
 
olympus said:
Hi there & a Happy New Year to one and all:)
just about to mount in the Eng./Gearbox cradle and i note that the threaded section on the end of the rear mounting stud is greater on one end than the other??
Is there a specific way the stud needs to be installed??

Many thanks
Click to expand...

do you mean the long stud (~14")? the thread should be the same on both ends ... I would assume thread lengths on both ends should be similar within a few thou, if not well you know what you should do...
 
grandpaul said:
I wonder why, as the mounting abutments at both ends are the same...
Click to expand...

I believe the idea is that with the nut screwed fully home on the short thread, the stud remains centred/centered (well, more-or-less) as the nut is tightened at the opposite end.
 
its nice that we have LAB to correct our oversights...:).. i'm gonna go out and check the one in the rebuild box... to see just how bad my focus is:rolleyes:
 
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Did not know or notice the differences in thread lenghts. I run a stainless one on the rear slathered in grease to prevent siezure.
 
I'm in Yeovil tomorrow on Business so my car might have a technical issue on the A303 at a place called Andover .... i have a list of Christmas prezzies to purchase so I'll ask Simon the reason:)
 
olympus said:
That can be right? ... why then just not fit a bolt rather than a stud
Click to expand...

Cost, probably?

Norton wasn't alone in making an extra-long 'bolt' out of a stud and nut. Triumph for one, did the same. For example, the long lower engine mounting bolt on the twins and triples (21-2112) isn't a 'bolt' but a stud with a tightly 'fixed' nut so why go to the trouble unless it was cheaper to manufacture?

https://www.ebay.co.uk/itm/Triumph-21-2112-Bolt-7-16-x-20-x-10-375-NOS-NP3570-/391265678917

As hobot says in the link, with the (nyloc) nut fully screwed onto the short end, the stud then acts like a bolt, the nut being the 'head' therefore prevents the stud from turning.
 
L.A.B. said:
Cost, probably?

Norton wasn't alone in making an extra-long 'bolt' out of a stud and nut. Triumph for one, did the same. For example, the long lower engine mounting bolt on the twins and triples (21-2112) isn't a 'bolt' but a stud with a tightly 'fixed' nut so why go to the trouble unless it was cheaper to manufacture?

https://www.ebay.co.uk/itm/Triumph-21-2112-Bolt-7-16-x-20-x-10-375-NOS-NP3570-/391265678917

As hobot says in the link, with the (nyloc) nut fully screwed onto the short end, the stud then acts like a bolt, the nut being the 'head' therefore prevents the stud from turning.
Click to expand...

Its still a poor engineering practise Les, i'm currently looking at some 320mm stainless bolts... might buy one just to see what it looks like
 
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