Replacing exhaust studs

[Pistacchio sprint 72]

These exhausts studs are a pain. They make the removal of the manifold awkward.
On my xflow kent i use classic bolts instead of studs + nut.

What do you reckon?

[msd1107]

Allen head bolts.

[RogerFrench]

Your Kent has an iron head. It's not bad practice to use bolts into iron, but it's better to use studs into aluminium. I know some people fit bolts for their manifolds (often Allen screws which makes access, removal, etc. even easier) but it's too easy to damage and strip threads in aluminium. Studs avoid that risk as long as the nuts can be undone.
If I felt I had to have bolts, I'd be thinking about fitting helicoils or equivalent first.

No doubt there are many who disagree!

[Pistacchio sprint 72]

Ahaaa you re right!

[Pistacchio sprint 72]

My studs are all rusty. I beleive something bad could happen when i will try to unscrew the nuts which hold my manifold

[rgh0]

Studs into castings both iron and aluminium are certainly better practice especially in high torque / high load situations. However the ease of access using socket headed set screws on the exhaust has won the day in my mind and on my twin-cam engines for the last 40 years.

Provided the threads are in good condition and you use a good anti-sieze ( I prefer Loctite nickel anti-sieze) when inserting the hex socket headed set screws and you are careful not to cross thread or over tighten them you will not damage the threads in the head even with repeated removal of the exhaust. As others have observed you can always fit helicoils if you want, though I have found this only necessary when I have got a head that had pre-existing thread damage normally from removal of a corroded stud.

If you shorten the studs to their minimum possible length and use reduced hex jet nuts or similar you can make access easier while still using studs but it is still a pain to work on depending on the nut access and chassis clearance you have with you particular exhaust.

cheers
Rohan

[alan]

imho please don't fit screws , for sure you will at some time damage threads in head as sure as eggs are eggs .
Fit studs in good condition and put copperslip grease on threads in head .
Use BRASS NUTS with spring washers.
How often do you remove the manifold

[Pistacchio sprint 72]

Ok you all convinced me

I want to change my old studs/nuts when i will take the engine/gearbox out.

Where can i get studs and these brass nut springs

[Pistacchio sprint 72]

And the spring washers...

[robertverhey]

Got mine on eBay from goughie

As you need 8 of each he'll do you a special order on request

http://www.ebay.com.au/itm/CROSSFLOW-EX ... 1e92252358

[rgh0]

imho please don't fit screws , for sure you will at some time damage threads in head as sure as eggs are eggs .
Fit studs in good condition and put copperslip grease on threads in head .
Use BRASS NUTS with spring washers.
How often do you remove the manifold

Well in 40 years I have not stripped a thread in the head, maybe I am just lucky or don't have eggs. Every time you struggle to assemble or remove the exhaust..... just smile and remember there was a choice.

cheers
Rohan

[Pistacchio sprint 72]

Rohan, where can we get quality screws with allen female heads?

[elancoupe]

Reduced length stainless studs are available, DBE and RDent are among those who sell them.

[oldchieft]

Reduced length stainless studs are available, DBE and RDent are among those who sell them.

Or just use a hacksaw !

Jon the Chief

[robertverhey]

Rohan, where can we get quality screws with allen female heads?

Rohan may chime in with a Melbourne contact, but up in Sydney, I frequently frequent this excellent establishment. What they ain't got ain't made!

http://www.yellowpages.com.au/nsw/north ... sting.html