Copperslip for Exhaust studs.

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Mon 20 May 2002 09:44
Copperslip for Exhaust studs. - Toad, of Toad Hall.
Is it possible to use copperslip when replacing exhaust studs or is there a better grease to use.

They were a little tricky to get off even after 7 days of regular WD40 bathing.

Also do hex sockets come in longish lengths? 4 Studs are *really* hard to get to and a 7 inch *long* hex that would fit into a socket would be perfect. An allen key would do but I need more beef behind it... [1]


[1] Currently using a 14 inch 1/2inch breaker bar with 8mm hex. I'm glad the studs were strong!


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Parp, Parp!
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Mon 20 May 2002 10:18
Copperslip for Exhaust studs. - Mike H
My information is that it would be foolish to use any grease at all in this situation. Two reasons:
1) putting grease on would enable the studs to be overtightened (as they will screw in more easily)
2) the grease will bake them in over time (i.e. it will turn into a very nasty solid mess which will make getting the studs out next time very difficult)
Similarly, wheel nuts/studs should also be put in dry but clean - using grease will once again cause them to be overtightened, but also when it melts with the heat there is a chance of contaminating the disc pads & losing the brakes.

I'm happy to be corrected, but I was always told never to use grease where heat is concerned. Anyone any comments?
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Mon 20 May 2002 10:27
Copperslip for Exhaust studs. - John S
Mike

Yes, torque figures are usually based upon dry and clean threads so there is a risk of overtightening if the threads are lubricated. Because torquing bolts isn't a particularly exact science anyway, I'd not worry to much as these bolts rarely have high torque figures.

Yes, there is a risk in using an ordinary grease that it will clog threads. However, provided a product like Copperslip specifically designed for use on high temperature bolts is used it should be OK. They are often used on bolts on steam turbine casings etc, to ensure that items can be dismantled.

Regards

John S
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Mon 20 May 2002 10:35
Copperslip for Exhaust studs. - Toad, of Toad Hall.
Thanks guys!

If copperslip *is* appropriate for heat then I'm not gonna worry about over torqueing.

I'm a trfle heavy handed so I tend to over compensate by putting nuts on slightly looser so overtorqueing won't be a problem.


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Parp, Parp!
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Mon 20 May 2002 11:24
Copperslip for Exhaust studs. - jud
I have always used high melting point grease on both spark plugs and wheel nuts or bolts, extreme care has to be used with the Audi wheel bolts to only give them a very light coating to prevent the chance of contaminating the brakes,(yes i know the owners hand book says dont grease wheel bolts) but not using any results in rust and problems with removing the bolts at a later stage.Also i coat the wheel "boss",the car was only six months old when i had difficulty changing a flat tyre, the bolts were difficult to remove and rust on the wheel "boss" had eaten into the alloy wheel, not impressive for a 20k car.
While having a tyre fitted at my local fitting shop i had the chance to look at a BMW 3 series, again the wheel bolts and hub was merrily rusting away, in contrast the previous three jap cars had wheel nuts and studs all galvanised.
I've not found any means of stopping manifold bolts from corroding.
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Mon 20 May 2002 13:08
Copperslip for Exhaust studs. - borasport20
i've always used Copaslip on exhausts and wheelnuts !

liberally on exhaust nuts & bolts, more sparingly on wheel nuts, as it seems to help limit the corrosion common when you have alloy wheels and steel wheelnuts

Torquing the nuts may be an issue, but given that 70/80% of wheels were probably fitted by fast fit operations whose compressed air spanners only ever seem to be set to "MAX + a bit more for luck..." I wont worry to much
when you've got tired of driving ...
www.mikes-walks.co.uk
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Mon 20 May 2002 16:12
Copperslip for Exhaust studs. - Cliff Pope
I can't see what's wrong wrong with a tiny amount of HMP grease on wheel nuts or hubs. The temperatures surely are not so high, compared with exhaust studs?

I once had alloy wheels so rusted onto the hubs that no amount of leavering would free the wheel. The onyl way was to loosen all the nuts and then do some fast cornering. And that happened in the interval between brake inspections. So now I grease everything, but very sparingly.
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Mon 20 May 2002 16:32
Copperslip for Exhaust studs. - Toad, of Toad Hall.
I once had alloy wheels so rusted onto the hubs that
no amount of leavering would free the wheel. The onyl way
was to loosen all the nuts and then do some fast
cornering.


Ever considered a career in the Railway maintainance industry Cliff! ;-)

Or NASA? ;-)


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Parp, Parp!
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Mon 20 May 2002 16:45
Copperslip for Exhaust studs. - BrianW
I've thought about the advisability of producing a list of components which should be removed at routine intervals even if no service or repair is required at the time.
On the old forum I posted a thread relating specifically to underslung spare wheel carriers, having had to cut through the bolt where a retaining hook had rusted solid on the thread.
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Mon 20 May 2002 18:07
Copperslip for Exhaust studs. - Daedalus
ToTH

Copper slip is the very best thing you can use on exahust bolts and studs! Its just what its designed for, and does what it says on the tin, ie lets you get them off again latter. I made great use of it as an engineer in the Merchant Navy on exhaust bolts on both the main engines and the auxiliary engines. The main engines developed over 30,000 BHP and had exhaust temps of upto 600C. Copperslip on the bolts ensured that they where always easy to get off.


Bill
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Fri 10 Jul 2015 17:50
Copperslip for Exhaust studs. - RomanMicheal

I'm only 13 years behind with this thread, but here's my t'uppence worth.

Halfords says....."

Halfords Copper Grease

Halfords Copper Grease helps to prevent disc brake squeal and protects against seizure. It can withstand temperatures of -40C to +1150C and is ideal for use on wheel nuts and bolts, exhaust brackets, flanges and studs as well as external hinges, screws, nuts and bolts.

Halfords Copper Grease Extra Info
  • Protects metal against corrosion, heat and water
  • Withstands temperatures of -40C to +1150C
  • Does not wash or burn off in normal use
  • Handy 20g tube
  • Suitable for use on wheel nuts & bolts, exhaust brackets, flanges & studs
  • Also suitable for use on external hinges, screws, nuts & bolts"

I used to work in the spanner trade many years ago and we always used copper "slip" on the back of brake calipers and on exhaust systems, especially the flange bolts.

Edited by RomanMicheal on 10/07/2015 at 17:59

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Sat 11 Jul 2015 08:25
Copperslip for Exhaust studs. - edlithgow

I've used aluminium foil, PTFE tape, and polythene sheet (from carrier bags) on wheel studs and hub surfaces, usually to supplement a very light application of grease.

Polythene would melt and char on exhaust studs. I'd think PTFE might be OK but IIRC I've only used aluminium foil there.

They make Aluslip, and if I could buy either (as opposed to making my own) I'd still use it in preference to coppaslip, though the advantages are probably largely theoretical in most applications.

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Mon 13 Jul 2015 09:47
Copperslip for Exhaust studs. - edlithgow

I looked it up. PTFE starts to degrade about 250C. Exhaust manifolds can go about twice that.

Aluminium melts around 650C, so should be OK.

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Mon 13 Jul 2015 17:53
Copperslip for Exhaust studs. - freman

How about Molybden disulphide ? I'm told this will stand atomic radiation,but I dont know about temperature resistance

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Mon 13 Jul 2015 18:35
Copperslip for Exhaust studs. - galileo

How about Molybden disulphide ? I'm told this will stand atomic radiation,but I dont know about temperature resistance

Usually OK to about 200 C but I believe some formulations are OK to 530 C.

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Mon 13 Jul 2015 18:35
Copperslip for Exhaust studs. - galileo

How about Molybden disulphide ? I'm told this will stand atomic radiation,but I dont know about temperature resistance

Usually OK to about 200 C but I believe some formulations are OK to 530 C.

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