Author Topic: 750 cylinder stud removal (Read 4892 times)

NickO · « **on:** February 07, 2012, 01:09:28 PM »

I've tried to do my homework and search this entire forum for advice on this and the posts seem to be how to remove a stud that has already snapped off?

I have successfully removed 15 of the cylinder studs. All but three came out without too much bother, (but were bloody tight). This was achieved by tightening each stud across its entire length in a 6" bench vice and turning the upper case. Each one gave a real "crack" as the thread "broke free" in the case. Two of the remaining three which would not respond to the above, were removed by heating the case around the base of each offending stud with a blowtorch until the oil residue around the top of the thread started to bubble and weep-out. This was followed by a sharp thump with a hammer on the end of the stud and then repeating the bench vice trick as above.

The last remaining stud will not budge, (despite two/three heat cycles). Each time I am rotating the upper case by approx. 1/8 of a turn (in both directions), but I can tell the stud is twisting and I DO NOT want to snap it off!

Has anyone any magic advice before my persistence ends in tears?

Sam Green Racing · « **Reply #1 on:** February 07, 2012, 01:19:02 PM »

No, it will snap in time. I removed several studs that were stuck when I was at Mikes, just soaking overnight with a proper penetrating oil (not WD40) and then heat. Only way I know Nicky. Try to heat the alloy not the stud.

Sam.

Darvill Racing · « **Reply #2 on:** February 07, 2012, 01:23:54 PM »

I have also used electrical circuit freeze spray on the stud just after heating the alloy in the attempt to cool the stud down quicker that the surrounding material...

Its worked thus far, maybe worth a 'punt' if all else fails.

Regards,
A

Doctor_D · « **Reply #3 on:** February 07, 2012, 01:29:45 PM »

There's a trick I got for a bicycle frame builder named Richard Sachs. He told me to pack dry ice around seized parts, and cover them with old towels to insulate them a bit, then smack the part with a deadblow. When I've had the patience to try it, it's worked.

At the shop we have a Milwaukee cordless impact driver that makes quick work of double-nutted studs as well. It's also great at removing those pesky Honda philips head screws.

Sam Green Racing · « **Reply #4 on:** February 07, 2012, 03:28:54 PM »

Quote from: Darvill Racing on February 07, 2012, 01:23:54 PM

I have also used electrical circuit freeze spray on the stud just after heating the alloy in the attempt to cool the stud down quicker that the surrounding material...

Its worked thus far, maybe worth a 'punt' if all else fails.

Regards,
A

Nick, I think the freeze spray might transfere to the alloy and make it contract to quickly, you just need the right amount of heat and a stud extractor close to where the stud enters the case, that should do it.
Have you got a stud extractor tool? I've got one if you need it.

Sam.

Sam.

Sam Green Racing · « **Reply #5 on:** February 07, 2012, 03:43:47 PM »

Nick, I also have a blow torch with a fine flame that can target the area without getting to much heat into the stud as well as the extractor. If you want to bring it round, you are welcome. Two pairs of hands are better than one.

Sam.

NickO · « **Reply #6 on:** February 07, 2012, 03:48:58 PM »

You are welcome anytime Sam. Have you got a Liverpool Visa, (being a "Manc" and all that)?

Sam Green Racing · « **Reply #7 on:** February 07, 2012, 04:06:34 PM »

I'm not a Manc

I just live quite close to the border.

I'm in Warrington a couple of mile off J21 M6.

Sam.

Darvill Racing · « **Reply #8 on:** February 07, 2012, 10:49:37 PM »

Sam to the rescue ;o)

lordmoonpie · « **Reply #9 on:** February 09, 2012, 03:24:03 AM »

I had the same problem - one flamin' stud stuck and the stud extractor would just twist the stud. I used PlusGas fluid and soaked it once a night for three weeks. It eventually gave way by actually tightening the stud first and once the corrosion seal had cracke it cam out easily with the plus gas. Patience is a tool I rarely find in my garage but it worked this time :-)

Jim F · « **Reply #10 on:** February 09, 2012, 05:56:54 AM »

Ive got 2 that are stuck on my build and have soaked them for a few days
I think its time to get the torch out and throw some heat to it

I have some stud removers but like Sam said
they just start to twist the stud

Jim

NickO · « **Reply #11 on:** February 09, 2012, 01:47:01 PM »

So the b*st*rd snapped, although it was inevitable as I could feel it twisting all along! This was depite loads of heat on the case and some instant freezer on the stud!

There was about 3mm remaining above the deck and it was a clean flat break and I managed to drill right down the centre of it by holding the upper case deck perpendicular on the pillar drill, (with a spirit level).

There was a noticable escape of trapped gas underneath the stud when the drill broke through, (anyone want to bid on ebay for some genuine 35 year old Japanese air?)

So now I have a 6mm hole right through the stud (15/64") and a size 4 left hand threaded stud remover tap, but the sod still won't budge. Anyone know how much safe torque you can apply to a size 4 stud remover before I have a set of scrap cases?

markb · « **Reply #12 on:** February 09, 2012, 01:53:23 PM »

I had one snap off too. Easy fix is to bring it where they can EDM (Electrical Discharge Machining) it out. Actually as long as you're drilling, and you're right on center, you might as well drill out the stud with the tap drill size and then just pick out the threads.

NickO · « **Reply #13 on:** February 09, 2012, 01:57:55 PM »

Mark,

I'm not 100% certain that I am bang-on centre, (very close, but not quite there). At 6mm there is no break through to the aluminium. Unfortunately, I do not have the confidence to drill-out to 6.8mm.

That stud must be really glued-in fast!

markb · « **Reply #14 on:** February 09, 2012, 02:03:29 PM »

I'd EDM it then. I don't ever trust those stud removers although if that breaks off you can still EDM so probably nothing to lose.

turboguzzi · « **Reply #15 on:** February 09, 2012, 03:51:23 PM »

stud removers are VERY limited in the ammount of torque they can take, never had much luck with them on really stuck studs.

Jim F · « **Reply #16 on:** February 09, 2012, 06:22:28 PM »

ok got one out and one to go

time to get the torch out

Jim

cougar · « **Reply #17 on:** February 09, 2012, 09:39:04 PM »

Hey 62tt ; On rare occasion. I've found that you can weld a nut around a stud or bolt down close to the place it's stuck. This will give you some extra torque close to the offending spot. Just a twisted thought. ...cougar...

NickO · « **Reply #18 on:** February 10, 2012, 01:13:19 AM »

Cougar,

The stud snapped-off less than 1/8" above the deck, and now it's got a 15/64" hole right down the centre!

markb · « **Reply #19 on:** February 10, 2012, 06:30:25 AM »

The welded nut is a good idea too. I've used that before with good success. You just might have enought sticking out to plug weld the nut to the stud. I let it cool about 15 seconds and then try while it's still hot. And if that breaks off you can still EDM.

MRieck · « **Reply #20 on:** February 10, 2012, 07:48:22 AM »

Quote from: turboguzzi on February 09, 2012, 03:51:23 PM

stud removers are VERY limited in the ammount of torque they can take, never had much luck with them on really stuck studs.

You and me both. I have somebody tig a nut etc (as mentioned) on there. The intense heat of the tig also helps to free up the stuck piece.

turboguzzi · « **Reply #21 on:** February 12, 2012, 07:43:41 AM »

welded nut idea sounds good to me! another little useful trick

bwaller · « **Reply #22 on:** February 12, 2012, 08:39:38 AM »

Right on welding on a nut. While it's hot work it back n forth gingerly and spray the loose nut to it. Hasn't failed yet.

Pecantree · « **Reply #23 on:** February 12, 2012, 11:42:39 AM »

After you TIG the nut to the stud, Whack it a couple times. It often will break free!
Good Luck
Steve

Jim F · « **Reply #24 on:** February 13, 2012, 07:45:16 AM »

I went and got some BP Blaster penetration fluid
soaked it for a night and put heat on
the next day. the last stud is out
good stuff

Jim

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Author Topic: 750 cylinder stud removal (Read 4892 times)