I'm in H...........perhaps you'll join us when we go down to the Road to the Sun...........Ed wants to ride.

Re. welding...............aint gonna happen; no welding equipment here and I have no skills in that dept.

Drilling and soaking, soaking and drilling................frig!

 

Ya got to be tough man.

The thermal shock is what breaks the corrosion, or at least that is my theory on why it works so well.

 

My 928 cents on this:

Given the picture wherein there are a few threads left on the bolt, the QuickCenter tool will work perfectly to enable a pilot hole to be drilled exactly on-center. Thus, subsequently drilling with larger and larger bits will very likely allow the shell of the bolt to be turned out with an easy-out, or, worst case, enable the bolt to be drilled-out right to the threads at which point a tap can clean up the remainder.

The other methods suggested, may work, but if they fail may destroy enough of the portion of the bolt now protruding from the block that later use of the QuickCenter tool becomes more difficult.

However, it isn't going to be fun to drill. You'll need a right-angle drill, will need to remove the radiator, and maybe even the condenser. Or, perhaps, a Dremel with the right-angle attachment.

Lok-tite "Green" might secure a nut to the remainder of the bolt. If it works great. Alternatively, the rest of the bolt might snap. It all depends upon what's going on with the remainder of the bolt. And you'd have to be careful to not lok-tite the nut to the block.

I suspect, and have been told, but never tried it myself, that the best way would be to weld a nut to the remainder of the bolt and then attempt to turn it out.

 

Greg beat me to it. And is the source of the not-yet-tried-by-me method.

 

I had to pull the alan bolt that held the front of the A/C expansion valve, and the head was stripped (well done, PO, well done). I tried everything I could think of, and the thing that finally worked was drilling a hole through the head and inserting a steel rod and using it to apply constant pressure while tapping gently on the face of the bolt head and applying generous amounts of penetrating oil. I can't tell if there is enough room to try this, and it's definitely a last-resort sort of thing, but it might work.

Edit: In regard to thermal shock, if you heat the unit up with a hand torch (kinda risky given that you'd be putting a flame on a gasoline engine), and then you can use a mixture of dry ice and acetone or denatured alcohol to cool it rapidly. You can switch back and forth between the two to generate thermal shock to break it loose

 

A MIG is cheap, and you to can learn to weld with one in maybe 15 minutes.

Everybody that works on old cars should have a welder.
It is one of the most used tools in my shop.

EDIT: I can say the welder is the most used tool when working on old Muscle cars and many others, but after owning a 928 for a while and if we are talking about just 928's, I think the multi-meter gets pulled out a lot more than the welder for it.

 

Dave great post. I was thinking, if you could loctite or weld that nut on, THEN centre punch and dril, and insert an easy-out or any sort of item you control, you theoretically have 3 good things going for you:

1) relieve pressure in the threads from the inside of the stud
2) control the inside of the bolt core
3) have as much as possible grip on the exterior of the threads.

So if you could manage to turn the inside (easy-out) as well as the nut (outside) you're in about the best shape you can be? Don't ask me, I'm just a computer security guy

 

At the meta-level the point of my post was: if you don't first use a method that's virtually-certain to deal with the bolt, other, less-certain methods may damage the bolt to the point where the original virtually-certain method is now not-so certain.

I'd never use an easy-out until I'd drilled a crap-load of the bolt out. And then, if the e-o doesn't work immediately I'd think of something else. Have you ever tried to drill-through an easy-out that snapped off and seized IN the bolt? I have. A long time ago. Learned my lesson. Never again. Easy-outs are really not meant for extracting things...

 

Note to self: buy a welder.

 

Anything that can grab either the inside or outside surface of the bolt, and grab as much as possible of it, has the best chance. So, if you can grab the inside of the bolt all the way along its shaft, even with a broken easy-out, you're best off. I have sucessfully drilled out the inside of a bolt, inserted a couple of drill bits, and shoved a screwdriver between them, to turn them then with suitable grip on the screwdriver.

 

ok.............just back from the garage.

After a few hours of soak I gingerly tried to move the FBB with Vgrips.............no budge. I didn't try to hard so I'll go to the local farm store tomorrow and seek a version of the QuickCenter tool..........I know they have big assed farm welding equipment

Ceasar time..............its a Canadian thing.

 

But, - and I think we are on the same page here - absent a welder, the most-certain methods involve drilling. I would not try lok-tite with a nut as my expectation would be that the rest of the bolt would just snap-off at the block. At that point, using the QuickCenter tool in that specific location is going to be a lot harder and the chance of not having a perfectly-centered pilot hole increases.

 

I should also add the rad is out and the 'old' WP could be used as a drill guide?

While we're on topic the 'old' pump is smooth casting so I assume Porsche but it has a 'cast' impeller..........is it a rebuild or an old original?

 

Malcolm,

I have a very lightly used small MIG that would be perfect for this type of work. I dont need it as I have a Miller 252 now. I would let you have it for $600, comes with everything but a bottle. For some gas money I could even drive it out to you this weekend and help you zap a nut on and get that out.
If it doesnt work. I have drill bits and a helicoil of that size.

Shoot me off an email if you are interested.

 

Porsche pumps come with either, your choice. Rebuilt ones have a clear sticker on them to that effect