Exhaust Stud Extractors

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the_priest
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Exhaust Stud Extractors

Post by the_priest »

Which are the best in terms of reasonable money. I have to remove all six from the Triumph's block as they are corroded and gaskets are blowing. I've got new studs, stainless nuts and new gaskets. They are 10mm into the block and 8mm blank and 20mm threaded for the nut.

I can loosen the radiator for access, should not have to take it off fully.

All advise welcome! Last resort is paying someone to do it, finances are tight after paying for son's accommodation for two weeks in Lyme Regis for his university project...
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Re: Exhaust Stud Extractors

Post by cheb »

First one one to try is two nuts wrung together, tightened up against each other. Heat will always help.
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Re: Exhaust Stud Extractors

Post by Le_Fromage_Grande »

Don't use a stud extractor, they nearly always break, the only way to get the broken stud extractor out is spark erosion, drill them out with a left handed drill bit.
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Re: Exhaust Stud Extractors

Post by Screwdriver »

I have found the best way to remove them is to weld a nut on and unscrew them while red hot.

Bring/send it here if you are able...
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Re: Exhaust Stud Extractors

Post by Mussels »

Have you snapped all 6 studs? If not do you need to remove them all?

ISTR there's a problem putting SS with Aluminium, they weld together. You didn't say what the new studs are made of.
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Re: Exhaust Stud Extractors

Post by mangocrazy »

Screwdriver wrote: Tue Jun 14, 2022 9:25 am I have found the best way to remove them is to weld a nut on and unscrew them while red hot.

Bring/send it here if you are able...
This is the only way that stands a decent chance of working. Stud extractors are a nightmare and will only make matters worse when they break. Avoid.

From what you say, all studs are still complete and not broken off? If so that gives you a better chance of success. The problem is corrosion between dissimilar metals (steel stud, aluminium cylinder head) and they effectively weld themselves together over time, heat cycles and corrosion. It's the fierce heat from the welding process that breaks the bond that has developed and allows you to unscrew the stud using the nut that's been welded on. As Screwdriver says, do this while it's still cherry red and before it cools down.

If it were me I'd remove everything in the vicinity including the radiator and especially any bodywork that could get damaged by sparks from the welding process.
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Re: Exhaust Stud Extractors

Post by wull »

When I had similar on a bike I managed to remove them all except for one with a snap on stud extractor set that I had borrowed. I had cheaper ones but these were the tits.

Drill the initial size then use the extractor.

The one remaining that was beyond gubbed I just drilled out then tapped a new thread and it was sorted.
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Re: Exhaust Stud Extractors

Post by mangocrazy »

A distinction needs to be made between stud extractors and 'easy out' extractors. This is a stud extractor:

https://www.lasertools.co.uk/product/39 ... ive-6-12mm

and this is an easy-out, also (euphemistically) known as a stud extractor:

https://www.toolstation.com/screw-bolt- ... set/p51010

Easy-outs are a complete waste of time, space and money. Avoid like the plague.

Stud extractors will do the job provided the corrosion between stud and head is not too bad. If the corrosion is bad enough it will have a sufficient grip on the stud threads that the stud will shear off when serious force is applied to the stud extractor. Either that or the stud extractor will slip, buggering up the stud thread. As you're replacing them anyway this isn't too much of a problem, but once the extractor has slipped its grip on the stud will be reduced.

It all really depends on the level of stud to head corrosion. If it's not too far advanced, stud extractors will probably work. If it's really serious I'd go straight to the nuclear option - weld nuts on the studs.
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Re: Exhaust Stud Extractors

Post by Druid »

I spend a bit of my working day removing corroded bolts and studs, this is the way I would do it.

Remove the radiator, it's a nuisance but it's more of a nuisance if you damage it.

Apply plenty of penetrating oil (not WD40) and allow to soak in
Two nuts tightened against each other on the stud. Give the end of the stud a good smack with a hammer, it often shocks the threads loose. Turn the stud bit at a time, working it back and forwards, keep applying penetrating oil. If the stud refuses to move do not keep increasing the force or you will snap the stud. This is the stage when you get the welder out.

Are the studs really that bad? Might be a better option to clean the threads up using a die and just replace the nuts. OE Triumph nuts are chrome plated steel iirc, or get brass nuts. I know stainless look good and don't corrode (much) but they're bastards for spalling if the threads are less than perfect
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Re: Exhaust Stud Extractors

Post by the_priest »

Screwdriver wrote: Tue Jun 14, 2022 9:25 am I have found the best way to remove them is to weld a nut on and unscrew them while red hot.

Bring/send it here if you are able...
Probably my very best option to be honest. I've just got to find the time and coordinate with you then, and a few beers and so on.

The studs are badly corroded, so much so that on the one side the nuts are almost gone. I've used some exhaust paste to bridge the worst of the gaps, but it is still blowing a bit. It would be easier to remove the radiator as well, so best I bring coolant for the refresh etc... fork oil? Hmm, not pushing my luck this time! :D :D
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Re: Exhaust Stud Extractors

Post by A_morti »

Screwdriver wrote: Tue Jun 14, 2022 9:25 am I have found the best way to remove them is to weld a nut on and unscrew them while red hot.
Can't be seized if it's a liquid!

Consider having a spray bottle handy, squirt only the studs as far as possible with the goal of cooling the stud while leaving the heat in the block. Yeh I know the block is aluminium and cools really quick but, in theory at least, you don't want the extra couple of thousandths thickness on the stud from thermal expansion but you do want it in the block.
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Re: Exhaust Stud Extractors

Post by mangocrazy »

A_morti wrote: Thu Jun 16, 2022 11:14 am
Screwdriver wrote: Tue Jun 14, 2022 9:25 am I have found the best way to remove them is to weld a nut on and unscrew them while red hot.
Consider having a spray bottle handy, squirt only the studs as far as possible with the goal of cooling the stud while leaving the heat in the block. Yeh I know the block is aluminium and cools really quick but, in theory at least, you don't want the extra couple of thousandths thickness on the stud from thermal expansion but you do want it in the block.
You're missing the point that the aluminium head will dissipate heat and shrink back to its former state more quickly than the steel stud, thereby clamping the stud. There's a reason for the old saying 'strike while the iron is hot'. I'd get the spanners on it and undo it as quickly as reasonably possible after welding.
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Re: Exhaust Stud Extractors

Post by the_priest »

And lo and behold, one stud is missing a nut! The other studs look more or less the same.

Image
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Re: Exhaust Stud Extractors

Post by maccecht »

Well you are the right man if miracles are needed 😇
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Re: Exhaust Stud Extractors

Post by Skub »

Is @Trinity765 not the resident expert on Triumph headers? :silent:
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Re: Exhaust Stud Extractors

Post by Trinity765 »

Skub wrote: Fri Jun 17, 2022 2:06 pm Is @Trinity765 not the resident expert on Triumph headers? :silent:
Indeed. Triumph studs are not designed to be removed by mere mortals - you'll need divine intervention for that.
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Re: Exhaust Stud Extractors

Post by MingtheMerciless »

I think rather than welding nuts on that's going to need Holy Water and a word with your Boss.
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Re: Exhaust Stud Extractors

Post by the_priest »

MingtheMerciless wrote: Fri Jun 17, 2022 2:38 pm I think rather than welding nuts on that's going to need Holy Water and a word with your Boss.
I can supply the Holy Water, but I reckon Screwdriver is most likely the best bet! Right now, I need to get through the next couple of weeks.
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Re: Exhaust Stud Extractors

Post by Skub »

the_priest wrote: Fri Jun 17, 2022 2:50 pm
MingtheMerciless wrote: Fri Jun 17, 2022 2:38 pm I think rather than welding nuts on that's going to need Holy Water and a word with your Boss.
I can supply the Holy Water, but I reckon Screwdriver is most likely the best bet! Right now, I need to get through the next couple of weeks.
A vodka & orange trumps holy water!

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Re: Exhaust Stud Extractors

Post by Le_Fromage_Grande »

If the rest of the nuts are there the header will stay in place, if nothing else the rust is going to hold it on :D
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