Oh boy...disaster.....
After 24 hours of pb blaster stuff on the cylinder studs, 13 of them came out easily. The next two came out with a bit of heat and some more strength. The last was very stubborn. I let it sit pb blaster for another night. This morning, I hit the engine block around the stud with heat, gave it another go with the stud extractor and bang....it snapped off at the base!
I drilled into the center of the stud, but have not gone any further (didn't drill all the way through the tip of the stud I mean). At this point, there is no damage to the engine block, so I thought this would be a good time to figure out what to do next.
Options as I see them:
- Use a screw extractor. I've had bad luck with these. With all the pressure that this stud withstood, how could a small screw extractor work?
- Drill out the screw entirely and (likely) helicoil the hole. Can you heli coil a cylinder stud? I'm betting the answer is no.
- Bring the engine block to a machinist to have it professionally removed.
I'm thinking that last option is the best. Thoughts?
Not as serious as it seems: on the flush-broken ones, drill thru the stud so the penetrant can work from both ends. The bottom end is usually stuck because it never had lube inside, corroded a bit. Even if you have to drill to the threads to remove these, they are easily Helicoiled later: I have done many.
A comfortable 'tip': hi-perf kits used to have mention of drilling these stud holes to a larger size, then Helicoiling to fit larger studs (custom, not available off-the-shelf) for use with turbo and real high-HP engines. Plenty of options available!
If you have stubs, have your welder ground TO THE STUD and weld a nut on the end. The heat expansion and galvanizing action of the current will break up the corrosion and they will come out much easier.
