Bolt removal with flux core mig
johnott
07-18-2020, 03:35 PM
While installing a water pump on an 02 Sonata, one of the lower 8mm mounting bolt broke as I was torquing it to spec.
About 3/8" protruding. Tried vice grips but they just rotate on the outside and chew up the bolt.I then decided to try my 90A HF flux core Mig welder. Tried about 8 practice welds with spare bolts and nuts but in every case the welds break before I reach 10 foot pounds (I need about 20 to free the bolt). Made two attempts on the actual bolt, same result. (I always let it cool down before attempting removal.) I am able to thread a nut onto the shaft a turn or so which holds it in place as I weld. But it is never strong enough. Thinking of moving to an extractor unless I can resolve the weld issue.
I don't have a lot of room, clearance directly in front of the broken bolt is about 5 inches from the fender wall. I can reach it by going in under the bottom edge of the fender and reach up... I never have a dead center shot, I'd say about 15-20 degrees below horizontal.
Is my welder under-powered for this job or is the bolt size too small to get a large enough accumulation for the weld?
If there is anyone with experience in this process, I'd like to hear your feedback. Thank you.
About 3/8" protruding. Tried vice grips but they just rotate on the outside and chew up the bolt.I then decided to try my 90A HF flux core Mig welder. Tried about 8 practice welds with spare bolts and nuts but in every case the welds break before I reach 10 foot pounds (I need about 20 to free the bolt). Made two attempts on the actual bolt, same result. (I always let it cool down before attempting removal.) I am able to thread a nut onto the shaft a turn or so which holds it in place as I weld. But it is never strong enough. Thinking of moving to an extractor unless I can resolve the weld issue.
I don't have a lot of room, clearance directly in front of the broken bolt is about 5 inches from the fender wall. I can reach it by going in under the bottom edge of the fender and reach up... I never have a dead center shot, I'd say about 15-20 degrees below horizontal.
Is my welder under-powered for this job or is the bolt size too small to get a large enough accumulation for the weld?
If there is anyone with experience in this process, I'd like to hear your feedback. Thank you.
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