A rider ...

[ndian22]

Agreed, if the stud breaks at a point which leaves just enough room to manage a weld but on a stud that's stuck tight enough to twist off using a "ultra small" wrench in the first place there's a high percentage chance the stud will shear again & this flush with the block. I've owned machine shops most of my life & almost every sheared stud that was brought into the shop was as a result of a home mechanic wanting instant results and twisting off multiple studs flush & requiring the head to be pulled in order to properly correct...very expensive mistake. Caution, patience and time prepping the effected stud with a good lubricant repeatedly & over an extended period...before using the above mentioned techniques will ensure easy removal but it's not quick & most won't wait for results. If you could be certain that the stud was a grade 8 steel then brute force would win out, but unless it was replaced at some point after the factory I'd bet that's a "butter bolt" stud...just saying. Small diameter ease outs are hard but snap easily wear eye protection if attempting cause those fragment like a small grenade. A a high grade left twist drill can be used more effectively as an ease out than the EZ- outs & are not quite as likely to snap ...drill outs can be difficult even when mounted on a vertical mill...home shop drill press not so good. Good news is if the stud snaps under moderate pressure it's really soft and will easily drill out, even at home.
Best advice don't twist it off, lol.     Rick C.  

[pd]

The kind of luck I've been having with this motor , I'm thinking I'll leave well enough alone and leave the studs be . I'll toss the insulator in the 'ideas that didn't work out bin' and try something else . Maybe see if the manifold gasket surface can be built up a bit to add some strength and to help curb warping . Maybe just double up on the manifold gasket .

How thick are the OEM mounting 'tabs' on the exhaust manifold ?
I've trued the gasket surface , but I'm wondering if the tabs are too thin ?

Pete .

[kartjockey]

Right before you gave up on the studs (probably the safest thing to do) I was about to offer an old trade secret that is so phenomenal I have had to kill (at least maim) anyone who repeated it!

[Ricks]

Right before you gave up on the studs (probably the safest thing to do) I was about to offer an old trade secret that is so phenomenal I have had to kill (at least maim) anyone who repeated it!

Send it to a machine shop?  LOL

[carryall]

    Does the "secret" involve applying powdered Liquid nitrogen, mixed with 50% unobtainium on the stud with a chicken foot?  LOL.

[pd]

Thanks anyway , Tom .
I'm in sorry enough shape . I don't need any maiming anytime soon . At least I don't think I do .

Rick ,

 I'm taking the crank case to a shop anyway , as I've found what may be a crack . I obviously missed it and don't recall ever seeing it before . It runs about 1/2"  from the front corner of the control cable mounting block , slightly forward and up toward the right front cylinder mount bolt .

I'm not positive that it is a crack , but I'm having it welded , just to be sure . Unless there's a good reason I should do something different . If so , please tell me .

There's also a crack in the right rear case mount rib that has to be welded , too .

Pete .

[kartjockey]

Where as aluminum can be dangerous with a torch (because it doesn't change colors and can melt before your very eyes!) heating the stud quite often is the answer.  Jamming two nuts on it is perfect if needing to re-use the stud. So once this is done find some paraffin wax.  I get mine in the canning section at the grocery store(gulf wax).  Heat the stud  up so much that when you touch the wax to it it flashes to a vapor.  Not much more then that though. This will let you know the temp is coming down to where you want it to be. Keep touching the wax to the stud until it quits flashing off and just melts.  The heat of the stud is now perfect and the wax can flow down into the threads to help lubricate the stud to screw out. At times more than one go at it is necessary but quite often proves successful.  And remember...patience is still a virtue so if you get frustrated just walk away for awhile.  Sometimes cooling all the way down and heating back up does the trick too.  Just my 30 year tenure chasing busted manifold studs out in my automotive life!

Carryall..where do you get your chicken feet from!?

[Ricks]

Pete, post a picture of the suspected crack.

[carryall]

 prescription from my new HMO witchdoctor.  I think Obamacare can hook you up too?

[pd]

Here are a couple pics of the 'crack' . Not as precise as I'd like them , but :





Basically , all that's visible is a shiny line .

Pete .

[Ricks]

Yeah, hard to tell if that is a crack or not.  Can they magna flux that?

[kartjockey]

hasto be magnetic to magna-flux.  There was a process that was mediocre at best but used a penetrating fluid that lit up via a blacklight.   Maybe could make up some plates to pressure test crank case.  Looks superficial tho.  Maybe take some clear acrylic seal like the ladies use to tier nails up.  And paint them closed to make sure if you don't test.  I like to drill and tap for tiny screw at end of crack to stop it ten seal.  If you know a good aluminum tigger thats a plus.  What does it look like on the inside?

[carryall]

    A couple other unconventional methods I've used before are...Honey.  Because of it's specific gravity, it will penetrate cracks/seams that water wont.  Also, I've used a small suction cup (kids dart gun, valve lapping tool, etc.) and see if it holds suction.  Because of the radius, and the slightly rough surface, a tiny amount of Vaseline on the edge of the suction cup MIGHT work.  Just a thought?

[pd]

I can't really see the imperfection in this pic ( 3 years ago ) , even after I blow it up . Unless I use my imagination .



I'll have to finish tearing the motor apart to get a better look inside , but I do see what looks like casting 'snakes' ( those little raised squiggles on some old aluminum castings ) . I suppose that's what is visible on the outside , too , but

There's actually a double radius : front to back and from the corner of the mount block where the line seems to originate .
Not sure I could get a cup to hold . It would have to be a pretty small cup .

Pete .

[carryall]

I see what ya mean.  Well...I hate to say it but... Ya might just have to put your lips on it and....suck on it?  LOL.  Please post pics,  if you would?  LOL