Snapped studs on exhaust/cylinder head

Deleted account 231205001

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Jul 19, 2003
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On my1100GS, I have three snapped studs (2 one side, 1 the other) on the exhaust manifold. Is there a way to repair them without taking the cylinder heads off ?. :confused:
Thanks for the reply. Will this method remove the old ones?. What I need it to do is remove the old snapped studs and replace with 'new' ones to secure the header pipes to the c/head.
If you haven't got any thread still showing your best bet is to buy some 'Easy outs'. These are like left hand thread taps. What you do is drill into the old busted stud as near to centre as you can, I recommend using a centre punch first, and screw the Easy out into the hole. As it is tappered and has a left hand thread the harder you tighten it the more you are trying to undo the old stud. One word of warning though, try to keep the turning movement as straight as possible because the easy out is made from a very hard steel and will snap if you try to bend it. It then is a bastard job to get the easy out, out. You can get easy outs from tool supplyers.

best of luck!
i have removed many snapped exhaust studs from vw boxer heads & would concur with paragon: heat head up & remove stud with lock nuts if possible (if it would have come out like that, it prolly would not have snapped) or with mole grips.

my tip: use really good grips. can be very dependant on quality of jaws. genuine "Vice Grips" are the daddy.

can take a long time to heat a head still attached to engine. oxy torch is handy if you know anyone who has one. be very carefull of melting alloy though :D

i would NEVER even consider using easy outs. if they snap, and they do, you'll probably be looking at a new head.
E-Z Out

Just check E-Z Outs in the following guide

The Mechanic's Tool Guide
Author unknown

Air Compressor:
A machine that takes energy produced in a coal-burning power plant 200 miles away and transforms it into compressed air that travels by hose to a Chicago Pneumatic impact wrench that grips rusty bolts last tightened 60 years ago by someone in Springfield, and rounds them off.

Aviation Metal Snips:
See hacksaw.

Battery Electrolyte Tester:
A handy tool for transferring sulfuric acid from a car battery to the inside of your toolbox after determining that your battery is dead as a doornail, just as you thought.

Craftsman ½ X 16-Inch Screwdriver:
A large motor mount prying tool that inexplicably has an accurately machined screwdriver tip on the end without the handle.

Drill Press:
A tall upright machine useful for suddenly snatching flat metal bar stock out of your hands so that it smacks you in the chest and flings your beer across the room, splattering it against that freshly painted part you were drying.

E-Z Out Bolt and Stud Extractor:
A tool that snaps off in bolt holes and is ten times harder than any known drill bit.

Eight-Foot Long Douglas Fir 2x4:
Used for levering a car upward off a hydraulic jack.

Electric Hand Drill:
Normally used for spinning steel Pop rivets in their holes until you die of old age, but it also works great for drilling mounting holes in fenders just above the brake line that goes to the rear wheel.

One of a family of cutting tools built on the Ouija board principle. It transforms human energy into a crooked, unpredictable motion, and the more you attempt to influence its course, the more dismal your future becomes.

Originally employed as a weapon of war, the hammer nowadays is used as a kind of divining rod to locate expensive parts not far from the object we are trying to hit.

Hose Cutter:
A tool used to cut hoses ½ inch too short.

Hydraulic Floor Jack:
Used for lowering a car to the ground after youhave installed new front disk brake pads, trapping the jack handle firmly under the front fender.

Mechanic's Knife:
Used to open and slice through the contents of cardboard cartons delivered to your front door; works particularly well on boxes containing such item as; leather seats, motorcycle jackets, plastic oil cans.

Oxyacetelene Torch:
Used almost entirely for lighting various flammable objects in your garage on fire. Also handy for igniting the grease inside a brake drum you're trying to get the bearing race out of.

Phillips Screwdriver:
Normally used to stab the lids of old-style paper-and-tin oil cans and splash oil on your shirt; can also be used, as the name implies, to round off Phillips screw heads.

Tool for calling your neighbor to see if he has another hydraulic floor jack.

Used to round off bolt heads.

Pry Bar:
A tool used to crumple the metal surrounding that clip or bracket you needed to remove in order to replace a 50 cent part.

Snap-on Gasket Scraper:
Theoretically useful as a sandwich tool for spreading mayonnaise; used mainly for getting dog-doo off your boot.

Timing Light:
A stroboscopic instrument for illuminating grease buildup.

Trouble Light:
The mechanic's own tanning booth. Sometimes called a drop light, it is a good source of vitamin D, "the sunshine vitamin," which is not otherwise found under automobiles at night. Health benefits aside, its main purpose is to consume 40-watt light bulbs at about the same rate that 105-mm howitzer shells might be used during, say, the first few hours of the Battle of the Bulge. More often dark than light, its name is somewhat misleading.

A tool for removing wood splinters.

Two-Ton Hydraulic Engine Hoist:
A handy tool for testing the tensile strength of ground straps and brake lines you may have forgotten to disconnect.

Used to round off bolt heads. If nothing else is available, they can also be used to transfer intense welding heat to the palm of your hand.

Whitworth Sockets:
Once used for working on older British cars and motorcycles, they are now used mainly for impersonating that 9/16 or ½ socket you've been searching for the last 15 minutes.

Wire Wheel Brush:
Cleans rust off old bolts and then throws them somewhere under the workbench with the speed of light. Also removes fingerprint whorls and hard-earned guitar calluses in about the time it takes you tosay, "Ouch...."
Thanks again for the replies. Have I got this right..... The stud itself ( IE the threaded bit x3 that sticks out of the cylinder head ) is actually screwed into the head and the exhaust header clamp slots over it and then you put a nut over that ???
If this is right, then a new thread will screw in and then I can simply replace the header pipe, clamp and then nut ( After the old one is removed of course ! ). Sorry, but my mechanical skills are basic to say the least.
I forgot to say, Halfords do a stud extractor set. I take it then that I should avoid this at all costs ?????
If the studs have snapped off within the head, get a new stud so you can see how much is left in the head. You can then get hold of a set of stud extractors (easy outs). select the best size to suit and then careful drill the end of the stud until you can get the easy out in with a good bight. (Practice on a old bolt so you know how much the drill bit may wander or how hard it will be to start it).

Then as Paragon said soak it all in penetrating oil for a couple of days then apply a bit of heat and ease the stud out.

A good coating of copper slip on the new ones and even the use of copper split nuts on the new ones should prevent this from occurring again.

Hope this helps.
Big Lad said:
One last thing. Do 'B*W' sell the replacement studs as parts ?

get some stainless studding from fastner shop & cut to length, then next time you need to take them out, they'll come out easy.

i can honestly say i've never had any success using penetrating oil. perhaps it's just me :rolleyes:
Cookie, I know I'm labouring the point........Is the stud threaded two ways, differing at each end, or threaded all the way in one direction. It's just that I thought the head stud was welded or something to the C/head, not actually screwed into it ????

PS. Sorry about not contacting you about MoH. We've not been able to get ourselves together. Have you got Call of Duty ?. Knocks spots off MoH. If you have, let me know. Cheers
just to clarify, as an airhead owner, i have no detailed knowledge of oilhead exhaust studs in particular. i do have a fair amount of experience of removing what i imagine are similar items from other machines though, and that is the basis of what i am passing on to you. i am not the best person i've seen at doing it either. best ppl are usually engineering shops. with big :GS:GS:GS:GS off pillar drills & milling machines.

a typical exhaust stud is an 8mm stud threaded M8 from each end, with an unthreaded shoulder in the middle. it is screwed into a threaded hole in the head & has a nut to hold the exhaust on.

if you cut a length of M8 threaded stud to the same length you can substitute it for a factory stud as the shoulder on the original serves little purpose.

although it is threaded from one end to the other, the threads will be the right way round when inserting into tapped hole in cylinder head or putting nut on to secure exhaust manifold clamp.

your stud may not be M8. it could be M6 which would explain why they apparently snap so often.

usually, if you get enough heat into the head + a really good grip on whats left protuding of the broken stud, it will come out. i've found that once the stud moves is a good time for the penetrating oil as occasionally the stud will turn half a turn & then lock solid like you wouldn't believe.
trouble is, the heat will boil it off sometimes.

other things i've learnt the hard way:

sometimes the thread in the head comes out with the stud.

sometimes it just will not come out & grips spin on stud

sometimes the stud snaps again flush with the head

any stud that is in well enough in that it snaps when turning on a perfectly good hex head in the first place will not come out by screwing a tapered bit of extremely brittle metal (easy-out) in to it and in so doing flaring the very thread you want to remove, so jamming it in even harder. easy my arse!

as you probably noticed, i think easy-outs are the tool of the devil.

i digress here but...there is a stud extractor system, that i have forgotten the name of, sold by snap~on & the like that consists of non tapered fluted tools that are driven into an exactly sized hole in the stud & then gripped with a special socket. these do work, but are very expensive. bit over the top for what you want to.

if the worst comes to the worst, you can drill out the broken stud & helicoil the probably knackered thread in the head. best left to someone who has done it before.
this may be possible with head on, but easier off.


i don't have COD & was off games, hanging on for half life 2. now that's gone to rat shit, i don't play much at all, not even MOHAA.

i did play max payne 2 wot i d/loaded & thought it was jolly good. not much use as it's single player only ;)

might consider COD. is it really different from MOHAA though?
I've now got the header pipes off to reveal the full horror of the damage.

The first pic shows where the thread has broken away from the head and the 2nd pick shows where it's gone !

The third pic shows the other port ( Right side sat on the bike ) with the other stud broken.

The question is........ Can the bit that's broken away be repaired or will I need a new head ?.... and can the other two broken studs be taken out using the methods shown earlier ?

I bought the bike in the summer with two broken studs, the third went recently. This is the first time I've ever had the pipes off. By the way, the wet stuff is WD40.

I'd appreciate any advice on repairs, but I think it looks as if I might need one new head for the left side.


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ooohhh! bl00dy hell - that looks a bit terminal. Quite a large chunk of head seems to have come away with the stud. Not many threads left to screw a new stud into - you now need a local engineering shop to advise whether the remains can be built up with alloy and re-drilled/tapped. 2nd-hand head may be cheaper, I suspect.

'kin hell :eek:

head must be made of cheese, and not much of it either round those studs. is this a common problem with oilheads?

if it were mine, i'd take the head off, get a REALLY good welder to build it up & machine it back again.

len at the cylinder head shop specialises in this sort of thing. not actually seen any similar repairs he has done, but he has done some other good head work for me.

if you do get a s/h head, make sure the studs aren't similarly bolloxed.
I was going to chane mine on an RS1100 but sold the bike before I did it.
bought studs,washers and nuts from Mwks.Not expensive.
Exhaust studs .30p+vat
Exhaust washers .33p+vat
Exhaust nuts £1.70p+vat
All bmw parts (never used them ,still here)
They list cylinder head at £97.50 s/hand if it is that bad:eek:
If it is any help:
The "bmw /motorworks supplied" studs I have are 4cm long threaded all along ,NO unthreaded shoulder.
good luck:)

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