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?

macafee2

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

macafee2

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.


macafee2

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.--:D

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

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.


macafee2

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?

macafee2

And brass nuts avoid this corrosion welding.--:D

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.

If you have several nuts to try to lock together you will always be able to find two that will lock together IN LINE.

As in my previous post. If the thread on those studs is still good DON'T try and remove them. You are just making un-necessary work for yourself.

It was me trying to help who broke the stud

secrets out now :)


macafee2

I don't think there is enough thread to get the nut back on. As best I could I had a measure yesterday. I was not looking forward to drilling it out but what else could I do? Trikey has now said that with enough heat I may be able to knock the stud out so will try that. I will put a nut on the end to protect the thread while I work, fingers crossed.
If all else fails it will be a replacement part that will be needed.

macafee2

The broken stud won't knock out as it is threaded.
However drilling it out shouldn't be too difficult.

I still here to offer help or just to break things :bowdown:

we have 2 opinions on this stud, threaded and splined

This is the stud and as there is a flange on top it wont unscrew and come downwards, the unit is still on the car.

Splined fits with my thinking. Drilling may be best but will try heating and knocking out.
if it get too stressed then I'll try drilling.

macafee2

Now that picture is very interesting.

Plenty of room for a nice Stainless Steel nut and bolt.---:D

Get that drill out and do the lot.---:bowdown:

Looking at the photo Ian I'd hazard a guess that they have been pushed in from the top and are an interference fit and may well be splined.

A combination of drilling out the centre, a bit of heat and a good seeing to with a lump hammer should get the broken one out. :}

sorry this is not my elbow, Number 6 sent me a picture of one he had as I wanted to look at the top. I Posted it to try and clear what seems to be confusion about splines or thread

macafee2

mmm yes that's an idea, use both methods. thanks mike.
I was going to use either or but both seems good

macafee2