Immovable stud

A hot air gun isn't really up to the job. You need a butane torch and getting the surrounding alloy so hot that oil (engine oil, not WD40 or the like) bubbles out from the threads surrounding the stud. Then there is a fair chance of shifting it. You may have to repeat the operation several times.

The hammering does sound like desperation.

Hello Can I askwhat condition the Stud in at this moment and the alloy around it First you need to flat off the stud, and then fit it under a pressdrillso it can not move, and find the centre of the stud and with a 1/8 cobalt Drill try drill a hole down the centre of the Stud you need to be down some 1/4 of an inch to get an easy out in, but first heat the the whole thing in the oven at full temperature for 20 min or so welder glovescomes in here and then clap it back down so you can get a Stud remover in has its hot then it should with any luck come out , all the best George

Hello Your going to ask me why put the whole thing the oven well alloyand steel expands at differentrates when heated in an oven so the steel will not expand has quick has alloy will and the heat will break the bond in the threads of the stud you need to take care and patients to remove it ease it a bit at a time you may have to heat it more than the once , but do NOT USE A HAMMER ON IT AT ANYTIME THIS ONLY MAKES THINGS WORST NOT BETTER YOURS ANNA J

Previously anna jeannette Dixon wrote:

Hello Can I askwhat condition the Stud in at this moment and the alloy around it First you need to flat off the stud, and then fit it under a pressdrill so it can not move, and find the centre of the stud and with a 1/8 cobalt Drill try drill a hole down the centre of the Stud you need to be down some 1/4 of an inch to get an easy out in, but first heat the the whole thing in the oven at full temperature for 20 min or so welder glovescomes in here and then clap it back down so you can get a Stud remover in has its hot then it should with any luck come out , all the best George

I have used Anna's technique many times successfully but I use a vertical mill. There is no chance of the hole wandering. The end mill goes right through the middle of the stud with no damage to the thread at all.

Hello George.

glad your helicoil went ok. i had the same with a rocker box stud. i tapped it up from the bottom not realizing it would get trapped it may have been bent i dont know. i found it better to tap it down . having said that i eventually welded a nut to the stud and also heated the cover up and gently rocked the stud from side to side with the spanner on the nut until it freed up then it came out ok .then fitted a new stud.

Baz

Be careful of what type of stud extractor you use if you go that route. The left hand thread variety have this habit of expanding the stud you are trying to extract and making things worse. The ones with a gentle taper and 4 crosswise projections in my experience are rather better.

HI George,

If it isn't threaded in, then why not try it under a press?

Even a large vice with some tubing over the stud to allow movement should do.

Good Luck,

George.

Loads of cycles of butane torch and oil first! You do need to get the stud and surrounding area really hot. If all else fails, you can drill the centre of the stud out - the heat and vibration of the drilling helps loosen it and it does take some of the internal stress off the stud. Then it should press out.

Previously George Phillips wrote:

Looks like a press is something else I've got to invest in! I'll have look at the vice idea (after cooking it) but it is the centre rear exhaust stud so is in a difficult location for fitting into a vice but I'll give it a go - any port etc....George

If the threads are OK, you can try using two nuts, locked together. Then, after cooking the rocker box as above, you should be able to get a good turn on the stud. Saves getting a press! Good luck.Kevin

How did you manage to remove the rocker box if the stud is stuck ... as it needs to turn to remove from cylinder head ????

Previously George Phillips wrote:

Hi Robert 'Cos the thread had stripped in the cylinder head so the stud just pulled out. It was the cause of the oily mist over the top part of the engine. I still haven't got it out despite having baked the rocker box. Tried drilling it with no success at all.Note to Anna - do you still give a hand with magnetos? The whole project is going pear shaped! George

Hello yes I still do Magento'sI rebuilt the one for my Norton Dominatormodel 88, 1954 vintage it had got some oil inside the mag now sorted and a nice big fat blue spark I am going to run the bike on these new plugs Champion N9BYC same heat range has Champion N5 but these new type are for ethanol fuels and made for a magneto no suppressor fitted, way not sent the lot to me and I sort for you, only pay forany parts used my time comes free to members yours Anna J email annajeannette@btinternet.com

just a thought George if it is stud 3 or 4 on the photo, if the stud has been drawn out before the others theres a possibility it may have threaded its self into the rocker box because the thread is the same size as the others but the stud is smaller so is the hole in the rocker box i looked at your explanation of which one you say it is but couldn't work it out hence the photo . Baz

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Hi George,

Are there any small general engineering companies near you? I'm sure that the cost of getting them to use a press on it would be low. What about your local car body repair shop _ would take seconds to weld a nut on it for you.

Alternatively, are there any other club members within a reasonable distance with good workshops that could help? Even if it is only for a second pair of hands.

A trouble shared is a trouble doubled (or something like that)!

Regards, George.

anyway George i get the feeling that you don't want my help so i will bow out and i wish you all the best with your project . Baz

Where abouts are you in the country George?

I brought this issue to an engineer friend (also a Norton builder) who suggested the stud may be "glued" in the rocker box to hide the stripped thread. He suggested it be bored out with a milling machine not pressed as that may destroy the casting. While he has a milling machine and would willingly help... he isn't in the UK.

Best of luck.

Previously George Phillips wrote:

Success! I finally managed to hold the rocker cover onto the plate of the press drill and after applying a fair bit of paraffin I was able to drill down and then twist and cajole it out. I'm really grateful for all the input, guys. Just got to sort out the magneto then put it all back together. Cheers - George

Congratulations! So it wasn't "glued" in, that's great.

Previously George Phillips wrote:

Success! I finally managed to hold the rocker cover onto the plate of the press drill and after applying a fair bit of paraffin I was able to drill down and then twist and cajole it out. I'm really grateful for all the input, guys. Just got to sort out the magneto then put it all back together. Cheers - George

Good to hear. Well done.