Extracting broken head studs with the engine still in the car

[proporsche]

Originally Posted by Rick Cabell

In no way do I want to rain on the parade of this thread. Hats off to the clever work.
But, I don’t want anyone who is new to this to think it is this easy.
I have replacing broken Dilivar head studs since the 80’s. I would say only 5-10 % can be removed using this process. The rest are in tight with locktite from factory. Last week I took apart a 3.0 SC engine. All 12 lower studs were broken, never seen that before.
The typical method with engine disassembled without pistons and cylinders is patience.
First I cut the stud if needed to about 3-4 inches remaining, if you have that much. Then weld a 10mm nut over the top of the stud. Yes, you can weld to dilivar. Then take an acetylene torch with a rosebud tip and heat the bottom of the stud in the cylinder opening. I keep a temp gun handy to monitor the temp as if you melt the aluminum, you are done. Once about 275-290 degrees the locktite gives. Still you have the work the stud back and forth slowly u till you can see you are home free and back it out the rest of the way. That is with a long ratchet over the end of the 10mm nut.

that is a lot of studs..12. the most i have seen is 6...i use the torch technique and Stahlwille stud removal tool...the biggest PITA is when the stud is broken flush against the case....

[Rick Cabell]

I use the snap on collet tool,if there are threads. If no threads to grab on to, I weld the nut. Never seen anything that will grab the stud good enough if there are no threads. Also, when you weld it shoots heat to the base to pre heat the locktite before the torch.

[Rick Cabell]

I was intrigued by your tool so I googled it. I went to 3 different vendors and they all said . Discontinued item. I see it has good internal teeth to bite.

[bkinghor]

Originally Posted by Rick Cabell

I was intrigued by your tool so I googled it. I went to 3 different vendors and they all said . Discontinued item.

I got through to the ~pay now button for the Koken 3128.80-8 for $36.98 at
https://palmac.net/koken-3128-80-8-3-8-nuttwister-long-type/ I have asked them about discount for bulk ... after a request I might make up a few stud extractor tools. At cost, plus a beer. However, not too difficult to make one for yourself. Ideally with a lathe, but possibly reducing the nuttwister with a fine-stoned bench grinder while spinning it in an electric drill.

[Nditiz1]

I'm in for an extractor tool. Tell me where to send the money and beer.

[john walker's workshop]

Originally Posted by Rick Cabell

I use the snap on collet tool,if there are threads. If no threads to grab on to, I weld the nut. Never seen anything that will grab the stud good enough if there are no threads. Also, when you weld it shoots heat to the base to pre heat the locktite before the torch.

An 8mm stud remover with the 3 rollers inside works great. AST among others.

[hienz]

I do not think this will work for the reason: How are you able to put the new o-ring in without removing the cylinder???????

[Rick Cabell]

John, I have used that 3 roller tool before, works some times, but not on the stubborn ones. Smooth rollers, smooth stud = no traction. I believe the other stud remover mentioned above has teeth inside to bite onto the smooth stud as you attempt to back it out.