Broken head stud mk 2

I was in the engine bay the other day doing a bit of cleaning , when one of the cylinder head nuts came off in my hand with a piece of stud inside it . One of the long studs with the lifting eye on it . I cut through the eye , thinking to use the rest of the thread and screw on another nut . No good , thread buggered ! There’s about an inch of stud sticking up above the head , what are the chances of getting it out without lifting the head ?

If you can restore the threads with a file (thread file or key file), what are the chances that you can fit two nuts on the remains? And why did it break i the fist place?

Hi Ken

Why did it break? Rotten, or excess force used tightening it? If the stud is rotten I’d soak it for a week with Plusgas or a mixture 50/50 of auto transmission fluid and acetone (nail varnish remover). I’ve read glowing reports about that mixture but haven’t as yet tried it myself so I’d do some research first to make sure that won’t eat the aluminium.

Then I’d use a pipe wrench to try to turn it but without too much force. Pipe wrenches get a really good grip but I don’t mean those you squeeze the handles, I mean those with a movable head which tighten up more as you apply more torque.

If it doesn’t move I’d repeat the operation.

Then, if it still won’t shift, and to avoid damage, I’m afraid I’d take the head off and send it to an expert. If it’s rotten this might give the best result anyway as others may be in the same condition and could fail at an inconvenient time.

But if it’s just had the thread stripped then get the pipe wrench on it straight away.

I would spray de ruster down the stud , leave over night , weld a nut on the stud , run engine till hot , then remove stud with nut , buy a new stud , easy lol


I think Ian’s idea of a welded nut is better than my pipe wrench :smiley:

It was rotten Bob , trouble is , there’s not much room to swing a wrench ! You mean a stilson wrench , used one of them to get the old studs out of the mk 7 , but the head was off , easy peasy ! If only I had a welder and was able to use it :frowning:

Positively no chance to double-nut then?
Atf-acetone won’t damage the aluminium.

Yeah, stilson is the word.

Had a bit of a word fart there, if it’s rotten you won’t get the head off as it will be stuck to the stud so it’s the whole thing off to an expert.

It’s easy to do more expensive damage if you try to use too much force either turning the stud or trying to lift the head while it’s glued to the stud. I speak from experience :rofl: :rofl: :rofl:

MIG welders are fairly portable (my brother has one) so you could ask your local garage nicely and I’m sure they would oblige.

But you have to soften that glue first!!

No David , thread useless .

Worth a try :thinking:
Stud Extractor – 12mm – M12 – Stud Remover | eBay

Would wd 40 do the trick ?

Maybe. I’ve used it to great effect over the years but it won’t get a long way into a seized up area whereas plusgas will, and I’m told that the ATF/acetone will actually eat the rust

Thanks Ian I will get one , worth a try .

What did you decide for your seats Bob ?

I’m committing the ultimate sin!

I’m looking for some more modern light coloured heated seats which I will make a bracket and sort some wiring for.

I’ll dye them and the rear seats a matching mid-blue.

I’ll keep the old ones in case the next owner wants them.

It will cost about a third of the cost of recovering just the front seats, and the (perfect) rear seats would have to be dyed to match the new front ones anyway.

They will be heated, which means i won’t have to mend the heater so soon.

Depends which stud Kenny, the stud second from the front, left side, has a locating boss at the block face, this prevents extraction through the head.
Some engines have a second stud with a boss at position 6 from the front, R / H side.

Hi Peter , it’s one of the centre pair . Going to try stud extractor first with gallons of plus gas :grin:

Putting a leaper on the bonnet would be worse :grimacing:

This toy is on my birthday list; watch the short video to see how it heats up the area and then the cooling effect would loosen up old rust and make removal a bit easier. It does sound like many other bolts cold also be suffering the same ultimate demise.


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Strange, the lifting hook/s usually are not fitted to the center studs, did you fit the longer studs to this position, and is the hook the MK2 Ali type or the later XJ steel type ?
I use one of the Snap On changeable collet type extractors that grip the thread, but if the thread can’t be chased.:slightly_frowning_face: