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Some alternative exhaust studs


Grim

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Hi, just thought I would post some more research, I was looking for exhaust studs, as mine had turned into exhaust bolts🤔.

I found various near misses, but wasn't happy with the thread lengths. I certainly my did not  want stainless (I have been stung before!).

I discovered some Ford models have nearly exactly the same studs for mounting Weber DCO/E carbs, the inner thread and smooth section are exact, the outer thread is a couple mm shorter.

Burton Power make performance parts for Fords, and so you can get 4 nice high tensile studs and 4 extra wide brass nuts for £10. 

 I love brass nuts, it appeals to my inner (or outward) coward; that brass will go long before the stud or head (that is the theory).

Here they are next to my old ones:

Fw0YsZJ.jpg

And in, but not nipped up yet:

akJFa0a.jpg

Compared to other studs sold as "Guzzi V11" parts on eBay etc. they are nice and cheap. And I believe they are a quality part.

https://www.burtonpower.com/stud-m8-x-45mm-inlet-manifold-each-studm8.html

https://www.burtonpower.com/brass-nut-m8-extra-wide-nbm8.html

Of course you could use the standard done nuts if you liked. 

Thanks for reading!

 

Edit: I have looked into them a bit further, they are Weber DCO/E carb studs

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1 hour ago, docc said:

Weber! The Italian connection!

So, how do you calculate the torgue for brass nuts? And Loctite?

Nice find. The torque should be the same as any grade 8 or 9 steel bolt as the torque is determined by the bolt/stud material not the nut material. You need to stretch the stud to maintain the tension so if the brass nut cant cut it then you need to go to steel or Titanium. I'm sure the brass nut will take the torque though esp if you opt for the extra long ones to give greater threaded surface area as thats the idea. 

Personally I'd go with a Titanium nut and anti sieze.

Ciao

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7 hours ago, docc said:

Weber! The Italian connection!

So, how do you calculate the torgue for brass nuts? And Loctite?

With brass nuts, I'm ashamed to say I just go with "tight.. but not too tight...."

I have put spring washers in there for a bit of tension before.

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3 minutes ago, Grim said:

With brass nuts, I'm ashamed to say I just go with "tight.. but not too tight...."

I have put spring washers in there for a bit of tension before.

Not at all, I've personally never used a torque wrench on exhaust studs or nuts for that matter in 50 years. As a matter of fact I dont use a torque wrench all that often. Just for critical fasteners and groups of fasteners that need to be tensioned evenly. The reality is its not a very accurate way to tension a bolt its just that its better than free hand for the overwhelming majority of people.

Get rid of the spring washer though, they are an embarrassment. Whenever I see spring washers i think "someone got the engineering wrong then".Buy a couple of Nord-Lock washers.

Ciao 

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1 hour ago, Lucky Phil said:

Whenever I see spring washers i think "someone got the engineering wrong then".Buy a couple of Nord-Lock washers.

Ciao 

You'd love owning a Yamaha XS650 then....

I think Yamaha would claim the spring washers are "insurance".

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Many aircraft engines use brass nuts on the exhaust. They won't rust to the stud and become a bolt. :oldgit: Spring washers work fine until they don't. They'll eventually break and leave a loose fastener.

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So, here's a thing.... The exhaust collars don't particularly want to easily locate on the new studs, the old studs are a little bent, and rusted away to practically 6mm round on the  non threaded part.

Now, the old ones came out as bolts because of the rust, so I never had to get the collar off over the bolts, should it slide freely on/off?

The threads on the head are clean and true, so I don't know if that mean my collars are warped or something?

Given that my new studs are a little shorter, I would rule out the angle between the studs becoming more obtuse as they get further out. 

Update:

Yes, they were bent...

QABxK9q.jpg

 

Quick introduction to Terry the 10 Tonne Press....

oSiRCPd.jpg

 

And we're on.

svZ1Vuq.jpg

So, how can I clean these things up, are they stainless? They certainly aren't magnetic!

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6 hours ago, Grim said:

So, here's a thing.... The exhaust collars don't particularly want to easily locate on the new studs, the old studs are a little bent, and rusted away to practically 6mm round on the  non threaded part.

Now, the old ones came out as bolts because of the rust, so I never had to get the collar off over the bolts, should it slide freely on/off?

The threads on the head are clean and true, so I don't know if that mean my collars are warped or something?

Given that my new studs are a little shorter, I would rule out the angle between the studs becoming more obtuse as they get further out. 

Update:

Yes, they were bent...

QABxK9q.jpg

 

Quick introduction to Terry the 10 Tonne Press....

oSiRCPd.jpg

 

And we're on.

svZ1Vuq.jpg

So, how can I clean these things up, are they stainless? They certainly aren't magnetic!

Dont bother, its a lot of work with the wire wheel,wet and dry, scotchbright etc and they just end up the same way before you know it.

Ciao

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