Exhaust nut question

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In regards to the variety of application using the exhaust tabs......
When I first reassembled my exhaust (74 850 w/crossover) I turned one tab into the head between the fins and the other tab into the exhaust nut between its fins.
I gave it a hard look, rode it a bit and decided it just was not an effective safeguard from my perspective, regardless of configuration or tab direction, so I ditched them.
The pipes are flared and the nut was almost bottoming out...just didn't feel right.

I use anti-seize on the threads with aircraft crush washers still employing the spherical flange and the split pipe collar
My son gave me the "special" tightening tool for my birthday and I used it to tighten the nuts on a hot engine, no sledge hammer involved.
They have not budged since I installed them and I check regularly.

I knew you would want yet another bit of input Joe. :D
always open for a bit more info, and back at ya - i bought (and modified) my "special" tightneing tool based on an on-line video. on mine, re-tightened several times after several heat cycles. in my case, i gave it a rap with a 1-lb, dead blow hammer. only when i felt everything was secure did i bend the exhaust nut tabs. in my case, i was no where near bottoming out the nuts.

Exhaust nut question
 
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I've just fitted these aluminium ones from Andy Molnar. They are half the weight of the chromed brass ones I had on before. They should expand and contract the same as the head. I was instructed to use copper grease. View attachment 81286
We'll see how they perform!
The logic sounds right, they look nice and @ £12.50 a pop, pretty good value I would say.
 
Who and where makes that spanner?.... I've got to have one of those... spark resistant too. Please great one share the knowledge with grasshopper so that he may sleep at night.
 
Who and where makes that spanner?.... I've got to have one of those... spark resistant too. Please great one share the knowledge with grasshopper so that he may sleep at night.
 
Who and where makes that spanner?.... I've got to have one of those... spark resistant too. Please great one share the knowledge with grasshopper so that he may sleep at night.
actually bought mine on fleabay - presently none available, but did find this source - https://sjbmw-parts.myshopify.com/products/cc-products-exhaust-nut-wrench .
shop around, might find it for less.

here's the video where i first saw the wrench. it has to be modified somewhat - on mine went a little further on the mod. works great!

 
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Seager Engineering make and sell on eBay a superb pair of nuts and a specific spanner

"NORTON COMMANDO TWIN ROSE NUTS WITH SPANNER" click on link : User ID seager-engineering

These look fab, but is stainless good for these nuts?

Seager Engineering are thoroughly recommended for head thread replacements

So they must know what they are doing?
 
Seager Engineering make and sell on eBay a superb pair of nuts and a specific spanner

"NORTON COMMANDO TWIN ROSE NUTS WITH SPANNER" click on link : User ID seager-engineering

These look fab, but is stainless good for these nuts?

Seager Engineering are thoroughly recommended for head thread replacements

So they must know what they are doing?
Looks like a great option, but being overseas, having to ship the head for sleeving the ports seems risky for me.
 
Hi

I am reading this thread with great interest as exhaust rose nuts seem now to be a problem.

Many years ago (40?) when I first had a Commando I do not remember them loosening and being a problem.

I have alway scrupulously cleaned the thead in the head and the rose nut before assembly and tightening.

I've always assummed that cleanliness would assist the rose nuts to keep tight due to increased friction
over the use of anti-seize, copper grease etc

I would have thought that copper grease (is this what is referred to as "anti-seize" by previous posters above? )
would melt and flow out over the head causing a copper coloured stain on the aluminium ?

Does the copper grease flow out ?

Especially when used as per recommendations above to use copiously?

Thanks for posting your experiences with the use of copper grease.
 
I would have thought that copper grease (is this what is referred to as "anti-seize" by previous posters above? )
would melt and flow out over the head causing a copper coloured stain on the aluminium ?

Does the copper grease flow out ?

Especially when used as per recommendations above to use copiously?
No it does not flow out on me, there is copious and just the right amount which for me is a generous smear but one man's copious is another's generous smear.

You should also be using it on spark plug threads to save the threads in the head from being pulled out by a seized plug.
 
Sooner or later, you will have to redo the threads. Many years ago a machinist, located in USA would offer beautiful OS (2inches) stainless nuts. I bought a pair for a friend I had to rebuild the engine. They featured a lock allen screw to prevent unscrewing. Unfortunately, I forgot the supplier's name. May be someone in this forum knows who I'm talking about.
That supplier was Sholtz Machine in Colorado and I had a set on my MK3, the did the head machine and made the nuts. I looked them up as I just completed a MK1. They went out of business about 5 years ago.
 
That supplier was Sholtz Machine in Colorado and I had a set on my MK3, the did the head machine and made the nuts. I looked them up as I just completed a MK1. They went out of business about 5 years ago.
You are right. Further search, I have been told Mr Georges Sholtz passed away. Too bad because, he made those 2 inches OS nuts. This is a very clever option, no sleeve insert just rethread , so no weakening of exhaust ports. The lock screw was genious too. Someone should resume the production, Matt at CNW should raise hand...Thank you for your input Jensen:)
 
Sergio,

I feel that the best solution is to use Comstock's Bronze inserts. This will once and for all take care of the thread issues and you can use any good quality stock size exhaust nuts available.

Over sizing what's already there will still leave you relatively soft threads and now your are committed to only one type of exhaust nuts.

If you have a Bronze insert, that has the correct threads and use a quality nut, then you will be ably to tighten this to a point where you don't have to worry about them backing out and a security lock isn't necessary

Matt
 
Judging by your name you don’t have an issue with the nuts loosening :cool:
Hi Landspeedracer,

You may already know already, but if not, Staytite nuts are similar to nyloc nuts, but the nylon is replaced
with a bit of spring steel causing it to be a lock nut, but reusable. Staytite stopped manufacturing Imperial
size stainless Staytite nuts a few years ago. I managed to buy a small stock of the UNF and UNC smaller sizes.

I have been using Imperial stainless Staytite nuts for several decades to stop my bits falling off :D
 
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