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Old 7th October 2019, 14:45   #1
macafee2
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Default what type of bolt is appropiate

one of the 3 studs that hold the exhaust to the manifold ( think this is where the joint is) has been snapped (not by me) and looks to be too short to reuse. I think I will need to drill it and use a nut and bolt. Due to the heat and cold cycling, what type of bolt is required?

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Old 7th October 2019, 15:07   #2
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I swapped my three manifold to turbo bolts (plus a stud on a 1.8turbo), for stainless steel ones. I did the same for the turbo to downpipe flange as well as the five M10 manifold studs/nuts. Stainless steel bolts/nuts retain their condition better than standard stuff.



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Old 7th October 2019, 15:17   #3
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Originally Posted by T-Cut View Post
I swapped my three manifold to turbo bolts (plus a stud on a 1.8turbo), for stainless steel ones. I did the same for the turbo to downpipe flange as well as the five M10 manifold studs/nuts. Stainless steel bolts/nuts retain their condition better than standard stuff.



TC
TC, how did you get the 3 bolts out? I thought they were part of the Triangle.
On this page, one of the studs/bolts that attach item 1 to 2 and held in place by item 4 is the bolt/stud that has snapped.
https://rimmerbros.com/Item--i-GRID001957

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Old 7th October 2019, 19:52   #4
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TC, how did you get the 3 bolts out? I thought they were part of the Triangle.

They're studs (threaded rods sticking out of the flange), so they have to be unscrewed. You can do this be screwing on and tightening/locking together, two nuts. You then use a spanner on the innermost nut so the stud is turned/unscrewed. You then replace the stud with a stainless steel version using the same technique in reverse. Some stainless studs come with an Allen key socket to make refitting easier. All this stainless stuff is available on eBay. Ensure to get the appropriate thread. I think they're M10 but best measure the stud diameter and length to be sure.


M10 Studs: https://www.ebay.co.uk/sch/i.html?_o...nless&_sacat=0


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Old 7th October 2019, 20:36   #5
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Originally Posted by T-Cut View Post
They're studs (threaded rods sticking out of the flange), so they have to be unscrewed. You can do this be screwing on and tightening/locking together, two nuts. You then use a spanner on the innermost nut so the stud is turned/unscrewed. You then replace the stud with a stainless steel version using the same technique in reverse. Some stainless studs come with an Allen key socket to make refitting easier. All this stainless stuff is available on eBay. Ensure to get the appropriate thread. I think they're M10 but best measure the stud diameter and length to be sure.


M10 Studs: https://www.ebay.co.uk/sch/i.html?_o...nless&_sacat=0


TC
thanks TC, that's a trick my dad taught me, omg, 40 or more years ago.

I'll take a look tomorrow. At the moment I cannot get the original nut back on the stud.

What stops the stud coming undone when the exhaust is removed and the nut undone?

I had a motorbike and when the nut was undone the stud in fact undid and came out, the nut stayed seized on the stud.


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Old 7th October 2019, 21:29   #6
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thanks TC, that's a trick my dad taught me, omg, 40 or more years ago.

I'll take a look tomorrow. At the moment I cannot get the original nut back on the stud.

What stops the stud coming undone when the exhaust is removed and the nut undone?

I had a motorbike and when the nut was undone the stud in fact undid and came out, the nut stayed seized on the stud.


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After a while in use the heat makes the stud seize into the thread.

If you don't want to have the possible problem having more snap off as you try to undo them, leave them in but use BRASS nuts, They don't seize on.--
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Old 8th October 2019, 10:14   #7
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What stops the stud coming undone when the exhaust is removed and the nut undone?

Different tightening torques. Corrosion apart, the stud will stay put because it's tightened into the flange to a significantly higher torque than the nut requires. So, slackening the nut afterwards doesn't slacken the stud. In some situations a high strength thread locking fluid might be used. When a stud slackens with the nut it's due to corrosion 'welding' the nut on.



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Old 8th October 2019, 11:24   #8
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thank you Colvert and T-Cut, really do appreciate the heads up that they are studs. Mike Noc thought they were, sorry Mike for not believing you. I thought they were part of the manifold. Two nuts fitted onto remaining part of stud, lots of penetrating oil being used. In the mean time I have struggled to remove the bolts for the rear anti roll bar... D rubbers need changing and perhaps so do drop links, these parts I have. Alas I have prodded a hole in one of the upper arms so I'll do that do.
Have shot blasted a spare and am preparing that for painting.
I can then go back to trying to remove the stud. I will set about the manifold with a blow torch first.

Am wondering if I should grind the corners off the lower nut so I can get a socket to the upper nut. May have more chance undoing it with a socket then a spanner. What do you think?. I'm still a bit stressed by this incident.


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Old 8th October 2019, 12:36   #9
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Colvert and T-Cut, nagging doubt would not leave me alone.
I have just used a mirror to look at the top of the triangle where exhaust pipe and item 1 meet. see https://rimmerbros.com/Item--i-GRID001957 items 1 and 2

There is no way they are coming out downwards. There is a flange on these bolts that is larger then the hole the have to come out of. If anything the bolt/stud needs to go upwards.

Are you thinking of the studs at the other end of the unit?

T-cut going back to your post 4, perhaps I should use the bottom nut, the outer one and tighten it. If threaded, tightening the nut will undo the thread in the triangle if there is one.

Can you advise?

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Old 8th October 2019, 22:10   #10
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Originally Posted by T-Cut View Post
Different tightening torques. Corrosion apart, the stud will stay put because it's tightened into the flange to a significantly higher torque than the nut requires. So, slackening the nut afterwards doesn't slacken the stud. In some situations a high strength thread locking fluid might be used. When a stud slackens with the nut it's due to corrosion 'welding' the nut on.



TC
And brass nuts avoid this corrosion welding.--

Over many years of fighting with manifold nuts, all the ones that came off without breaking the stud I've changed to brass.

Never had a problem afterwards either.--

PS. Just spotted on Rimmers site that the do sell the brass nuts too.
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