How much heat to head stud?

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1

69 Coupe

Doing a lot of different things lately as I re-assemble. Have been squirting acetone/atf mix on my long studs for a month. No budge yet!! The first one broke about 1/4 " above block, at bottom end. Can anyone provide an idea of how hot I can heat a stud, thru the core plug area, without causing block damage. ie., red hot, x degrees via heat gun reading, etc. I have read EVERY thread, current and archive on this topic. If this doesn’t work, off to a Jag machinist, but I’d rather not.

Mark
Murrieta, Ca.

2

I had one stubborn remaining stud that I used the “dbl-nutted with an impact wrench at 2 sec bursts” method over a period of one week and a concoction of 3 penetrating oils. It finally conceded.

3

If you can aim a direct heat onto the stud with oxy just run it up to red hot and try turning the stud.

4

I am still allowing mine to soak…just haven’t had time lately, so hot these days here, and perhaps savoring my victories thus far with the A+ condition of block, bores, and head…

Iron is quite resilient…should be no problems heating that up well at the base. Heating red hot shouldn’t be necessary. Ok if only done a couple times…
However i would (and intend) to spray it down and cool first with lubricant prior to attempting to loosen.

Keep an eye on it below while attempting to turn so not to snap it.
Still not giving? Repeat ad nauseum. Doesn’t have to get red hot. I intend to heat only the stud end where attaches at block.
They should give eventually unless completely bonded.

If giving only a little, stop, and tighten again, repeat.

It’s what an old friend, the master mechanic at classic jaguar in Austin taught me as a kid many lifetimes ago (and different management fyi).
Always worked with everything and he knew his stuff. Has his own shop now i think.
Strange, i can still recall that smell as it evaporated. Funny.

Perhaps it was smell of victory!

Despite the condition of my studs (see my thread), and a couple down to pencil widths on intake side, they did come out without heat.
Haven’t done exhaust side yet, which although more robust, were really rusted. Bonding concerns me there.

Definitely intend to heat thos prior to attempting.

Also, i have been recommended kroil here and by those in the know who swear by it.
I intend to try it worse case…

UTube has some interesting vids for motivation if anything.
One needs it often times with these things.

Please update how it all goes for you.
Kind regards

5

I would slide a nut over the stud and weld it together with the stud. This would induce enough heat into the whole remaining stud in the block. Then use a socket to remove the nut and the stud.

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6

Doubtful on a long stud engine, the heat has a long way to travel down to the base of the block.

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7

How about trying the candle wax method? Seems to work on the most stubborn nuts.

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8

Sorry to be blunt but stop messing around and give it to a professional.

If in trying to get those studs out you crack your block it’s a throw away.

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9

Do you have an arc welder?

Connect the ground clamp to the block, and the rod clamp to the stud: apply juice (if a pedal-operated one— for about a second, then try it.

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10

clamp right on the stud, no electrode, eh? First time I heard that one. What do you do if you don’t have a pedal operated arc welder? Can you flick the switch on/off without disaster and how many amps are we talking?

11

Also commonly used by plumbers to thaw frozen pipes.

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Id use 20-30 amps, and yes, just turn on switch. No more than a second or two.

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69 Coupe

Thanks for all the comments! To Abowie,…down deep, I have to agree with you, however, it’s hard for me to do unless, all hope is gone! Additionally, even though I live in Southern California, I have had difficulty locating a shop that I KNOW has the ability to work on Jags. Right now, my #1 option would be to either crate the block and send to XK Unlimited or drive it up myself (about 4 hours north of me). I wrote to some members of the San Diego Jag club, but never received any definitive info!

I read about everyone who has had difficulty, but after time and soaking etc., they were able to extract them. I’m going to try the electrode thing! I will re-post if any luck, or not! Again, thanks to everyone who has offered assistance.

Mark
Murrieta, Ca.

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Four hours each way is a small price to pay to have it done right. That said, I’d be surprised if there isn’t a quality shop in the San Diego area or further north in LA.

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69 Coupe

John, you and all the rest are right, I know it! It’s just real hard to not keep trying. I just think, one more time and it will give! One more time, etc etc. I’ll post when I have finally thrown in the towel, yelled Uncle and loaded it up for transport!

Mark
Murrieta, Ca.

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16

Fwiw, your thread motivated me to take a moment and try one of the exhaust side studs as described which i feared could be fused.

Heated and cooled a couple times as described, repeating when i reached a rough patch did free it using a stud puller (concentric lobe type).

So there is hope.

17

Years ago I wrote about my experience with my rust eaten stud. Soaked and used heat for weeks. As a last ditch effort I cut the top of remaining stud with dremel tool. Proceeded with a long drill bit to drill out. In the process of the drill turning clockwise I saw movement of stud. Came out with my fingers.
I had also cut a slot on top with no success. Try tightening the remaining stud.
Glenn

18

I think you have to plan ahead to avoid making things worse. If the stud is sheared 1/4” above the base you have to expect that it will need drilling out and helicoiling. Since it will be subject to large loads it can’t be bodged like, say, a timing cover or sump fastener might get away with. To do the helicoil as good as new will need special adapted drilling/tapping and insertion tools. Unless you are certain you can perform pro-quality repairs you’ll need to pass the block over at that stage anyhow so hoi might as well give them the extraction job too. If you’re unlucky, arc welding can leave hard crystalline spots that make subsequent operations far trickier.

Basically, if you can’t resect the appendix, don’t open the abdomen.

If you can, pm me for a lead on the tools.

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19

Hi Mark, I feel for you…I was lucky…all my long SII studs came out with a stud remover. I used penetrating oil and a propane torch. I wonder if there is any benefit from using induction heating on the remaining studs. I think Pate said it all re the broken one.

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20

69 Coupe

Final comment on this subject, then we can all move on to other issues. I tried heat/cool, heat cool etc one more time last night on the least corroded stud. Above the block deck, the stud twists as tension applied, but nothing at the base. At 0130, I officially threw in the greasy towel and cried Uncle!

I chose the one that broke because it was more than 1/2 gone at the base and figured that if that didn’t move, the rest surely wouldn’t either. I’m not going to spend 4 years taking it apart and then back together and not do it right! There are some things, externally that can be changed later, but turning the key for the first time and hearing a “bang” or some other not-so-good sound after all this work is not what I’m working toward!!

I will post a pic of the block when I get it back to show that I did, in fact, cry Uncle! Thanks for all the help!

Mark
Murrieta, Ca. ** cooler today; only gonna be 101 degrees