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Conquistador_del_mar
04-23-2010, 11:18 PM
Whenever I have had to remove a broken bolt in an engine block, I always used a drill and an easy out. When I discovered that one of the water pump bracket bolts was broken off in my Cigarette, I told my welder who was about to do a small job for me. He asked if I wanted him to use his special rods to get it out since it was very difficult to get a drill down there. Maybe some of you already know about this procedure, but it was new to me. Don had a case of special rods for rebuilding the shanks on a broken bolt that he then welds a nut on to it for removal. It worked like a champ - broken bolt came right out!! Bill

superhatz
04-24-2010, 01:31 AM
I'm usually digging a broken stud out of aluminum....so I MIG weld a nut on and most times, it comes right out....:)

Good times!

MOP
04-24-2010, 07:20 AM
If they break below the surface try a set of reverse (left hand turning) drill bits, between the heat from drilling and the rotation most wind right out. Then there is the trusty old blue wrench, I would not be without a B tank!

Conquistador_del_mar
04-24-2010, 09:52 AM
I'm usually digging a broken stud out of aluminum....so I MIG weld a nut on and most times, it comes right out....:)

Don mentioned that a neighbor of his wanted to hug him after he used the special rods for this procedure to remove two broken bolt studs in an aluminum Volkswagon block. Do you use any special rods for building the shank to the nut?


If they break below the surface try a set of reverse (left hand turning) drill bits, between the heat from drilling and the rotation most wind right out. Then there is the trusty old blue wrench, I would not be without a B tank!

What is a blue wrench? In my case, the bolt was broken below the surface. It was the lower bolt below the water circulating pump neck on a BBC so it was difficult to get there. My drill would not even get there due to the engine compartment bulkhead without trying to use an angle drill. Don had to cut his rods in order to get the stinger to clear the bulkhead. It only took about 45 minutes to do the entire procedure and he let me wrench the bolt out. Highly cool - :yes: Bill

wufwee
04-24-2010, 10:10 AM
I agree left-handed bits really work. I use a small pneumatic 90% drill, center punch the stud, drill a small hole (slow and steady wins the race). I drill completely thru the stud, spray pb blaster in there. The I use the next size bit, and when it bites, it turns (usually) the broken stud right out whether it's in cast iron or aluminum.

MOP
04-24-2010, 11:29 AM
Another good tip, use a drift pin punch and tap the broken bolt fairly hard. Think for a moment when you tighten something the upper thread surface of the item contacts the lower thread surface of the item you are screwing into. That is what creates the stiction that holds it tight, by giving it a shot with a punch you break that stiction making it easier to remove when you do get a grip on it. Standard easy outs many times make it harder to remove things as the expand the item, always leave enough meat to try to alleviate that problem. Another trick I learned from a machinist buddy is to make up cutter type easy outs out of square tool stock, I only have a few but I made them over 30 years ago they all still look new and I have never broken one. Now we all know how sweet it is to break one of the hardened spiral type!!!!

Having worked in salt all my life I learned a few other tricks, one is to hit a bolt head with a punch from side to side this breaks the head stiction making removal easier, I proved this to my buddy who does old boat restorations. He had a big old flat head six that sat out in his yard for a few years, he said it was juck and going away. I asked why he was not going to rebuild it, said can get it apart!! I said if I get the head off will you have it done over, well not thinking he said $20 it is not going to budge! RLOL 30 minutes later the head was off including three bolts he had rounded off trying, we could not believe our eyes the engine looked bristol inside no rust no scoring. I said get a bar and lets roll this thing over, a 1-1/2 foot piece of heavy rod stuck in the hand crank dogs and it rolled over real nice, it has since been gone through and is in some old saw dust bucket roaring along!

Oh almost forgot the "Blue Wrench" the B tank should have been the tip off HEAT is your best friend working on this stuff.

Dr. David Fleming
04-24-2010, 11:47 AM
Often when I am restoring an antique boat engine - 80years old I will find a steel bolt broken off in an aluminum casting. Could be steel in iron or whatever. This broken bolt often has had enough corrosion over the years to really present a serious removal problem.

An industrial service offered in the Detroit area for manufacturers in this situation is called EDM - Electrolic Discharge Machining. It is often used when a major industry must sacrafice an expensive machine or part because a tap or drill or bolt has broken in a critical location. They ship the part and it is removed by a process which is the reverse of welding.

Tasty way to fix an irreplacable engine part.

superhatz
04-24-2010, 12:15 PM
Often when I am restoring an antique boat engine - 80years old I will find a steel bolt broken off in an aluminum casting. Could be steel in iron or whatever. This broken bolt often has had enough corrosion over the years to really present a serious removal problem.

An industrial service offered in the Detroit area for manufacturers in this situation is called EDM - Electrolic Discharge Machining. It is often used when a major industry must sacrafice an expensive machine or part because a tap or drill or bolt has broken in a critical location. They ship the part and it is removed by a process which is the reverse of welding.

Tasty way to fix an irreplacable engine part.

EDM is great if you can ship or bring the part to someone....the machine shop two doors down from my shop has one....:)