Mild steel studs and stainless nuts?

[Kayos]

I am swapping the exhaust on the Disco and I have a vague and hazy memory that mild steel studs and stainless bolts are a good idea if I need to strip it again?

Or am I just better sticking with normal stuff?

 

[TechnicAl]

Probably corrode and stick even more......I think Manganese Bronze are used by Rolls Royce....but never having had one its just heresay.

 

[gordon stephenson]

All decent cars used to have "brass" nuts, Always around a nut and a half long.

 

[carbon]

Have a look for ‘galvanic corrosion chart’

 

[Ruffian]

All decent cars used to have "brass" nuts, Always around a nut and a half long.

I have around 200 of these to help with manifold swaps. Make life so much easier if need to remove again

 

[wristpin]

I have around 200 of these to help with manifold swaps. Make life so much easier if need to remove again

Even Suffolk lawnmowers used to have "brass nuts" holding the muffler to the exhaust stub! Still got a few.

 

[Dcal]

You need an electrolyte to get galvanic corrosion.
Can't see there being much in an exhaust manifold unless you are planing to regularly ford estuaries or the like.

I've used A4 stainless nuts on mild steel exhaust studs and they have always come apart without issue.
The real bonus is the stainless nuts don't rust away.

I do use brass if i have them though.

 

[TechnicAl]

You need an electrolyte to get galvanic corrosion.
Can't see there being much in an exhaust manifold unless you are planing to regularly ford estuaries or the like.

I've used A4 stainless nuts on mild steel exhaust studs and they have always come apart without issue.
The real bonus is the stainless nuts don't rust away.

I do use brass if i have them though.

road salt plus moisture

 

[Farside]

road salt plus moisture

Accelerated by heat.

 

[Dcal]

road salt plus moisture

Seriously?
How long is the moisture going to last on an exhaust manifold.

Sure it's a theoretical risk but it wouldn't keep me up at night worrying.
Any sensible person would put them together with a bit of copaslip or the like (no matter what nuts and bolts are used) which would also exclude any moisture.

It has worked well for me.

 

[james butler]

i use these https://www.ebay.co.uk/itm/BMW-E30-E21-EXHAUST-MANIFOLD-PIPE-HEAD-STUD-NUT-M8-NUTS-HEX-FLANGE-COPPER/171182218537?fits=Car+Make:BMW&hash=item27db415d29:g:dQoAAOxyXDhSpbPt:rk:4f:0
they come off really easily and the style of nut seems to last well from expansion and contraction.
only downside is they do tend to wind the stud out too when undoing them buts thats probably because i haven't torqued the stud down properly first

 

[Ruffian]

Seriously?
How long is the moisture going to last on an exhaust manifold.

Sure it's a theoretical risk but it wouldn't keep me up at night worrying.
Any sensible person would put them together with a bit of copaslip or the like (no matter what nuts and bolts are used) which would also exclude any moisture.

It has worked well for me.

Sometimes dealing with barn finds and restorations of cars and tractors it seems modern stuff is rotting well.
Had a 2012 Peugeot in yesterday and had to remove manifold to weld it and the studs were rotten.

I found out whilst swapping exhausts that sometimes to replace the studs was easiest.

Screwfix do these in bzp and stainless.
Just needed cutting to length
https://www.screwfix.com/p/rawlplug-studs-bzp-m8-x-110mm-10-pack/2885f

 

[pedrobedro]

Brass ones from eBay always work for me. Our Kia had stainless nuts at the exhaust to manifold joint and two of the three sheared the studs and I was not trying that hard. They felt like they had started to go then the stud just gave up.

 

[whm_fab]

i wouldnt use stainless nuts, ive seen it and have had a b$tch of a time removing them from customers cars. i use new copper flange nuts on all exhausts. fit and forget. will come off as easy as the day it went on

 

[bigegg]

Seriously?
How long is the moisture going to last on an exhaust manifold.

overnight.
every night.
so 16 hours a day?

 

[PhillipM]

Nah, bad idea, the heat will burn off any lubricant and once the rust sets in from the moisture/heating cycles when you try to take them off they gall up and sieze.
The only time I've seen them work half well was stainless studs with silver plated nuts.

As someone else said, either copper/bronze or normal steel nuts.

 

[bricol]

Seriously?
How long is the moisture going to last on an exhaust manifold.

Sure it's a theoretical risk but it wouldn't keep me up at night worrying.
Any sensible person would put them together with a bit of copaslip or the like (no matter what nuts and bolts are used) which would also exclude any moisture.

It has worked well for me.

theoretically thats even worse ;-)

I use a really high temp stuff thats known in the state of california to kill you . .works well. As an antiseize that is. Not been very good at the other so far!

But I use brass or "copper" nuts too.

 

[Farside]

theoretically thats even worse ;-)

I use a really high temp stuff thats known in the state of california to kill you . .works well. As an antiseize that is. Not been very good at the other so far!

But I use brass or "copper" nuts too.

Never-Seeze?
I jealously guarded my small tin of it for 30 years and only used the last dregs a couple of years ago. Back then, it was like chicken teeth, unicorn farts, etc to get hold of, but now it's just a push of a button away. If my next tin lasts half as long I'll be happy.

 

[Mr shiney]

I use stainless nuts on my motocross bike which spends most of its life under mud and water and never have a problem removing them from the studs.......

 

[TechnicAl]

Seriously?
How long is the moisture going to last on an exhaust manifold.

Sure it's a theoretical risk but it wouldn't keep me up at night worrying.
Any sensible person would put them together with a bit of copaslip or the like (no matter what nuts and bolts are used) which would also exclude any moisture.

It has worked well for me.

absolutely serious.......and thats only from the outside