As per the title really. I know there are normally studs with copper nuts but are normal cap head bolts ok and would it be ok to mix and match?
Thanks,
Mark
I have! Stainless ones, though I would doubt it would make much difference.
Adrian
Copper is used to stop seizing.
quote:
Originally posted by AdrianH
I have! Stainless ones, though I would doubt it would make much difference.
Adrian
i was going to, but wasn't keen on screwing them into, and back out of a ali cylinder head, so someone suggested getting a length of stainless threaded bar/studding or whatever its called, and cutting it up into the right size pieces. the whole lot should cost about the same as 1 'proper' stud.
quote:
Originally posted by blakep82
i was going to, but wasn't keen on screwing them into, and back out of a ali cylinder head, so someone suggested getting a length of stainless threaded bar/studding or whatever its called, and cutting it up into the right size pieces. the whole lot should cost about the same as 1 'proper' stud.
ooh i thought they were just the job because they don't corrode? didn't think of galvanic corrosion, would have thought steel would have been more of a problem though?
Have a look at a galvanic series graph like this: http://www.corrosionist.com/Corros1.gif
The further the metals are apart (in mV), the greater the risk of galvanic corrosion. So yes, indykid is quite right.
Damn, i knew I shouldn't have use all those gold and platinum bolts!
I've just fitted a new exhaust front to back on the car and it had stainless studs and nuts between the manifold and front pipe. All three of them snapped like carrots and were impossible to drill out, I had to replace the manifold.
Cheers for the reply - so if I use normal 8.8 steel capheads and put some thread lock on to stop corrosion?
id have thought that if you use thread lock on an exhaust manifold when it gets upto temp it will just burn away?
if they're zinc plated steel, there's even less chance of galvanic corrosion
quote:
Originally posted by indykid
if they're zinc plated steel, there's even less chance of galvanic corrosion
Never had a problem with std steel studs, brass nuts and copper ease on the threads.
I think the 'copper' nuts are steel with a flash of copper.
[Edited on 16/6/11 by wicket]
quote:
Originally posted by Peteff
I've just fitted a new exhaust front to back on the car and it had stainless studs and nuts between the manifold and front pipe. All three of them snapped like carrots and were impossible to drill out, I had to replace the manifold.
I have found that using bronze nuts is the best thing for high temp situations especially on turbo's etc! They always come undone and my preference is for steel studs but A286 stainless is suitable if you want to go that route!
Why not just use what is recommended by the engine manufacturer, at the end of the day they are the experts.......
quote:
Originally posted by Greenie
Why not just use what is recommended by the engine manufacturer, at the end of the day they are the experts.......
quote:
Originally posted by indykid
Stainless in an ali head would be inadvisable. Galvanic corrosion will either eat the threads, or lock the two together solid.
You can always cut down long set screws if you want high tensile studs, or even socket caps if you want really meaty studs.
quote:
Originally posted by deezee
quote:
Originally posted by indykid
Stainless in an ali head would be inadvisable. Galvanic corrosion will either eat the threads, or lock the two together solid.
You can always cut down long set screws if you want high tensile studs, or even socket caps if you want really meaty studs.
Galvanic corrosion requires more than just two metals in contact! Usually road salt and water need to be added. So unless your exhaust never goes hot enough to dry the outside of the engine, and your using it in winter, you don't need to worry about this.
Stainless bolts will be fine, mild steel bolts will be fine. Its really nothing to worry about.
Normal BZP studs with copper washers and brass nuts is the correct way to do it. People on ebay even sell kits of studs and it would cost less than
£10 to do it properly, so why bodge it?
Stainless is a bad idea in an aluminium head, its ok if its somewhere you can use loctite which will stop any corrosion forming, but you can't do
that on exhaust studs.
quote:
Originally posted by flak monkey
Normal BZP studs with copper washers and brass nuts is the correct way to do it. People on ebay even sell kits of studs and it would cost less than £10 to do it properly, so why bodge it?
