Lebro Posted April 10, 2022 Report Share Posted April 10, 2022 If you look at my photo above, you can just see a stud remover with serrated cam hiding in No. 1 cylinder ! (It didn't work - just ripped up the stud surface) Bob. Quote Link to post Share on other sites
Brian Eldred Posted April 22, 2022 Report Share Posted April 22, 2022 On 4/10/2022 at 8:39 AM, Lebro said: If you look at my photo above, you can just see a stud remover with serrated cam hiding in No. 1 cylinder ! (It didn't work - just ripped up the stud surface) Bob. Well it worked for me, that stud removed successfully My problem is the one that's sheared off about 3mm above the block face. It's the rear stud by the heater valve. I've bought a fluted extractor kit, the American Pro one. Took a while as the first supplier was out of stock. However I'm making no progress drilling the stud. First I used a nut over the remaining stud and one of the guides in the kit, with a hand drill - there's no room for my drill stand. The drill snapped. Tried another drill but made no impression. I then ground the stub flat, centre punched it and tried a smaller drill, but all I've got so far is a dimple. It seems very hard, so I guess I need better drills than standard HSS. Would Cobalt do the trick? Though I believe they snap easily. That magnetic drill press looks good, but a tad expensive to drill one hole! Brian Quote Link to post Share on other sites
Lebro Posted April 22, 2022 Report Share Posted April 22, 2022 It sounds wrong, but try a masonry drill, they have a tungston tip, & I know the ground angle looks all wrong, but they will work. Just last week I was helping a fellow TR owner change an anti toll bar link on his Mitsubishi Shogun one nut would not undo, so we ground off the end. Which left a trapped hard steel threaded part. I tried a selection of hss bits all of which just got blunt very quickly, then tried a masonry bit, which worked. They don't produce the normal swarf, more like a powder. Quote Link to post Share on other sites
Brian Eldred Posted April 23, 2022 Report Share Posted April 23, 2022 I tried a masonry drill, but don't have any new ones and it didn't make much impression. But then i found a set of cobalt stubby drills I forgot I had, and these are working fine. However I'm now wondering which size extractor to use and how much torque they will take. I've drilled out to 1/4'', progressively up to 6mm then using the 1/4'' drill that came with the kit. However the hole has wandered off centre somewhat and I'm concerned that the next size up, 5/16'' might hit the threads. Also I have a 7mm cobalt drill, but 5/16 is just under 8mm so would again have to use the HSS drill that's with the kit. I'm tempted to try the 1/4'' extractor, but I guess once they are banged in they are hard to get out again? I can't find anywhere online that says what torque these can take, and the worst scenario is that I snap it . Anyone have any experience with these on a 1/2'' head stud? Sorry I hi-jacked the original topic.... Brian Quote Link to post Share on other sites
Howard722 Posted April 23, 2022 Report Share Posted April 23, 2022 I wouldn`t try a conventional left hand pointy type extractor. in my experience they snap! If your hole has wandered off centre the best solution I have found that has worked for me is to get hold of a rat-tail round file, or maybe a bit bigger, and cut a length of with a grinder so that you can mount it in in your power drill chuck with enough exposed length to reach down your bore hole. Now with patience power up the power drill which is now a rotary file and bring your hole back on centre by eye and persevere gently until you get it right then go for progressively bigger drills. A combination of effort should eventually see the old stud thready bits break apart and you can fish them out and eventually bring a tap into play or a matching bolt with generous vertical slots cut into it to clean up the thread and help with the broken thread bits. Quote Link to post Share on other sites
Brian Eldred Posted April 23, 2022 Report Share Posted April 23, 2022 8 minutes ago, Howard722 said: I wouldn`t try a conventional left hand pointy type extractor. in my experience they snap! If your hole has wandered off centre the best solution I have found that has worked for me is to get hold of a rat-tail round file, or maybe a bit bigger, and cut a length of with a grinder so that you can mount it in in your power drill chuck with enough exposed length to reach down your bore hole. Now with patience power up the power drill which is now a rotary file and bring your hole back on centre by eye and persevere gently until you get it right then go for progressively bigger drills. A combination of effort should eventually see the old stud thready bits break apart and you can fish them out and eventually bring a tap into play or a matching bolt with generous vertical slots cut into it to clean up the thread and help with the broken thread bits. Hi Howard, it's not a pointy type extractor, it's the parallel fluted type with a nut that Mick pictured above. I might try your tip to enlarge the hole though, as the larger the extractor the less scary! Quote Link to post Share on other sites
Motorsport Mickey Posted April 23, 2022 Report Share Posted April 23, 2022 Hi Brian, so the rear short stud by the heater hole has been flattened just above the block surface and then partially drilled but the drill has wandered slightly off... always a problem, and not helped by the engine angle tilted backwards which throws off your eye when drilling freehand. Pity you couldn't get your drill stand onto the top block surface and then strapped down with cargo straps... sometimes even a magnetic DTI stand clamped to the block is enough to abut the drill stand against providing a solid surface to strap against movement. I would continue as your above conversation and see if the hole can be recentred and then try drilling again opening out the hole to leave the minimum of material around the threaded form in the block, then try entering a tap (taper first ) and pick up the thread leading edge exposed before gently turning the tap into the thread form and hopefully ejecting the stud remains from out of the thread. If the above can't be done then the recentering of the drilled hole (the above method with rat tail file sounds...interesting and hopefully works) should allow another drill to be passed down the centre of the stud and the appropriate flute selected to go with the drill size. As I've said I've used these extractors to remove a 3/8th sheared bolt and I anticipate it came out with about 60 lb ft but because of lack of repeatability of sheared bolts I think applied torque is down to the operative. The torque needs to be varied on-off and as the flute flexes (they are tough rather than hard) the applied load needs "feeling" and occasionally held on to give the stud a chance to submit. If in the event you do shear off the fluted drive they are in no way as hard as a tap or there aforementioned "easy outs" and should be able to be cut flush for operations to continue against the sheared stud. For inspirations check out this out https://www.youtube.com/watch?v=7JCfEMrCjhc Mick Richards Quote Link to post Share on other sites
Brian Eldred Posted April 23, 2022 Report Share Posted April 23, 2022 Thanks Mick, I was hoping you would chip in with your pearls of wisdom. I'll look for a cylindrical file drill attachment first before trying to make my own I think. Maybe a job for the Dremel. I'll be taking the 4a out for Drive It day tomorrow! Just put the battery on charge... Brian Quote Link to post Share on other sites
Brian Eldred Posted April 27, 2022 Report Share Posted April 27, 2022 Update: it's out! . I used this 6mm tungsten carbide grinder in my Dremel (first one I bought was the wrong size) to centre and open out the hole to near 5/16'', then drilled out with the 5/16 bit that came with the kit. Was a bit nervous hammering the extractor in as it was reluctant and only went in half way, but I shifted it with a ring spanner on the slip over nut. Huge sigh of relief... Quote Link to post Share on other sites
Motorsport Mickey Posted April 27, 2022 Report Share Posted April 27, 2022 Yep… these fluted extractors give you the best chance when you have a sheared bolt, they are tough and will take a good torque. Good result. Mick Richards Quote Link to post Share on other sites
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