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Author Topic: Exhaust stud removal  (Read 1577 times)

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Offline Sherlock

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Exhaust stud removal
« on: September 23, 2012, 04:19:24 am »
Looking for help and advice.

CB550f2 ss

Managed to remove 3 studs but the others are stuck fast. 

I have snapped 2 :-( the remaining 3 have been heated, soaked (for a week) and I've used various thread removal tools.
One of the studs has been replaced with a slightly larger one.
Can the sheared off studs be drilled out and Heli coiled?
Any other advice before I take it to a machine shop?



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Online Terry in Australia

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Re: Exhaust stud removal
« Reply #1 on: September 23, 2012, 05:13:31 am »
It depends on what equipment and skills you've got mate. If you can drill the broken studs out at the exact correct angle, then it's easy enough to go small-bigger-biggest with the drill bits, then use a helicoil kit to replace the drilled out threads.

You might get lucky and get the broken ends out with "Easy Outs" (a contradiction of terms, if ever I've heard one) but don't count on it. It's super important that the studs are drilled at exactly the right angle though, and if you don't think you're capable, take it to the machine shop.

How have you been heating the studs? You need plenty of heat, either a propane torch (good) or an oxy-acetylene torch. (better) Get them hot, not hot enough to melt them, but a nice "dull cherry" color is good. You can "double nut" them if you're gonna try to save them, or grab them with vice grips and undo them while they're still nice and hot. I've found that a combination of heat and quenching with WD40 works well for me, but there might be a better way. Cheers, Terry. ;D 
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Offline mono

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Re: Exhaust stud removal
« Reply #2 on: September 23, 2012, 05:53:48 am »
Yikes I'd be ultra careful using oxy-ace around aluminum!   

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Offline Retroben

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Re: Exhaust stud removal
« Reply #3 on: September 23, 2012, 04:06:04 pm »
The broken ones you're going to have to drill, and if you don't have precision drilling capability, you will only make matters worse. Take it to a machine shop. If you do have a good precise drill press and the right bits, you might try drilling very small in the center of the broken stud, then gradually larger until you get large enough to insert the smallest size (professional quality!) screw extractor you can find - after soaking with penetrant and heating. But remember this steel-to-aluminum can stick incredibly tight, so you might then end up with more trouble in the form of a broken extractor ("easy out", right, like diarrhea).  Unless you're a machinist, don't be penny-wise on this one. Trust me.

If you're taking it to a machine shop anyway, let them do the whole job - including removing the remaining studs (if necessary). You might order the studs in advance and take them in with you, unless your local machine shop has the equivalents in stock (don't count on it).

My two pence/cents/pesos worth.


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Re: Exhaust stud removal
« Reply #4 on: September 23, 2012, 06:19:59 pm »
++++1. I would not attempt the extraction without the right equipment and expertise.
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