Best way to remove exhaust manifold studs from cylinder head

[Danez]

oreyt
been removing the head from my talbot express due to a holier than thou exhaust valve

Just wanting to remove these exhaust studs from the head now and wondering what's the best way to do it without snapping them?
i'm reyt chuffed that i've managed to get the exhaust manifold off without snapping owt, used a lot of heat mind

my first attempt would be with more heat and a set of mole grips, failing that a couple of nuts locked together and an ugga dugga or even weld a nut on
what do we reckon
i've used copious amounts of penetrating fluid to help too

cheers

 

[ajlelectronics]

Clean with a good wire brushing, add magic releasing fluid, lock two nuts together and have at it. I have also got a set of stud removers which have done a great job with studs that you don't want to keep.

 

[Morrisman]

I’d weld a nut on each one, get it nice and hot, then use that solidly fixed nut to tweak it back and forth tiny bits at a time. Don’t try to wind it out in one go, and even get the stud really hot with a blow torch, so the heat transfers into the head and expands it.

 

[Danez]

Clean with a good wire brushing, add magic releasing fluid, lock two nuts together and have at it. I have also got a set of stud removers which have done a great job with studs that you don't want to keep.

magic releasing fluid such as plus gas?

 

[123hotchef]

magic releasing fluid such as plus gas?

ATF and accetone mix works best plusgas second, id also heat them up

 

[ajlelectronics]

magic releasing fluid such as plus gas?

ATF / Real Acetone. You can't buy anything that is as efficient.

 

[addjunkie]

As its on the bench….heat and a bug pair of sthilsons!

 

[Danez]

cheers for the advice
they're currently soaking in some atf (don't have any acetone)

bonus pic: the reason this thread exists

 

[ajlelectronics]

ATF on its own is too thick. Try thinners, see if it mixes. Otherwise, diesel is a good one part release agent. The Acetone allows the ATF to get where it is needed before evaporating and leaving an oil film.

 

[arther dailey]

just remember , thinners ,plus gas are all highly flammable , so if/when you do put heat on...I would go double nut , if they dont move then weld on the nut the heat sent through normally does the trick.

 

[Red'n'Black]

bonus pic: the reason this thread exists

View attachment 459919

Blimey, that's good and proper mullered. Any idea what caused it?

 

[Danez]

ATF on its own is too thick. Try thinners, see if it mixes. Otherwise, diesel is a good one part release agent. The Acetone allows the ATF to get where it is needed before evaporating and leaving an oil film.

ahh i did think that..... i could mix it with some white spirit?

 

[Danez]

Blimey, that's good and proper mullered. Any idea what caused it?

nope! thankfully the piston is fine!

i can only guess the valve gaps weren't set correctly so maybe it got too hot? going to test the other valves with some fluid and compressed air.

the third position is proper clean so it must have been running on three for a while

 

[OJCar]

Any idea what caused it?

Mice

 

[ajlelectronics]

Mice

More like pedigree Siberian Hamsters.

 

[ajlelectronics]

ahh i did think that..... i could mix it with some white spirit?

Try it. It is a bit slower to evaporate but that may not matter so much.

 

[Memmeddu]

We use stud remover sockets at work.
We clean the stud using a wire brush on a die grinder.
We heat the head around the stud .
Then we use the socket to break it loose hopefully.
Back and forward applying WD-40.
Some of them snap anyways.
So we proceed to drill at tapping size, hopefully drilling through the stud core only.
Then we use a very thin semi round chisel made out a pin punch, to roll over the remaining threads on the stud.
Compressed air to make it pop out.
Sometimes we manage to use a pick remove the threads like a wire coil .
Once it's cooled down we go through the hole using a tap .
And if it cuts we have enough thread contact surface.
We try the new stud and if it doesn't wiggle in the hole we have succeed.
If not we cut the threads to apply an heli coil.

Not that easy to be honest as the best way is using an hand held drill .
Because they never snap flat and above the surface so even with a milling machine using short carbide drills is too risky to drill sideways or worst snapping the bit in it resulting in a pita, because nothing we have is capable to drill through a carbide drill .
So an hand held power drill with a bit of practice is still the best tool for the job
Because you are able to adjust the angle and drill through the centre of your broken stud .

You can get the job done with a very rigid set up on a milling machine, plunge cutting the first mm and then use a spot drill once found the perfect centre, and switch directly to tap size drill bits.
But this requires a lot of time to set up, tons of indicating all directions, assuming the sealing surfaces on the head are perfectly flat and square (very unlikely) , using a precision level ,a lot of bracing on the head to avoid chatter, dro runs , and your machine has to be perfectly square and leveled, bolted to the ground on a vibration deadening surface.
And most importantly minimal run-out.
We don't have any of those upmentioned requirements on our machines at work, plus we work in a hurry all the times, so no time to do all this for just a broken stud .

Hopefully you'll don't need to remove any broken stud on this job

 

[ajlelectronics]

applying WD-40.

Were they wet?

 

[Danez]

We use stud remover sockets at work.
We clean the stud using a wire brush on a die grinder.
We heat the head around the stud .
Then we use the socket to break it loose hopefully.
Back and forward applying WD-40.
Some of them snap anyways.
So we proceed to drill at tapping size, hopefully drilling through the stud core only.
Then we use a very thin semi round chisel made out a pin punch, to roll over the remaining threads on the stud.
Compressed air to make it pop out.
Sometimes we manage to use a pick remove the threads like a wire coil .
Once it's cooled down we go through the hole using a tap .
And if it cuts we have enough thread contact surface.
We try the new stud and if it doesn't wiggle in the hole we have succeed.
If not we cut the threads to apply an heli coil.

Not that easy to be honest as the best way is using an hand held drill .
Because they never snap flat and above the surface so even with a milling machine using short carbide drills is too risky to drill sideways or worst snapping the bit in it resulting in a pita, because nothing we have is capable to drill through a carbide drill .
So an hand held power drill with a bit of practice is still the best tool for the job
Because you are able to adjust the angle and drill through the centre of your broken stud .

You can get the job done with a very rigid set up on a milling machine, plunge cutting the first mm and then use a spot drill once found the perfect centre, and switch directly to tap size drill bits.
But this requires a lot of time to set up, tons of indicating all directions, assuming the sealing surfaces on the head are perfectly flat and square (very unlikely) , using a precision level ,a lot of bracing on the head to avoid chatter, dro runs , and your machine has to be perfectly square and leveled, bolted to the ground on a vibration deadening surface.
And most importantly minimal run-out.
We don't have any of those upmentioned requirements on our machines at work, plus we work in a hurry all the times, so no time to do all this for just a broken stud .

Hopefully you'll don't need to remove any broken stud on this job

bloody hell yeah i really hope they don't snap now after reading this
but yeah cheers for the advice

Try it. It is a bit slower to evaporate but that may not matter so much.

i've given it a go, cheers!

 

[Memmeddu]

Were they wet?

Probably
I think we use WD-40 because is manly solvents and it is very thin oil so it travels enough fast through the threads