woodycooper
Seaman
- Joined
- Sep 6, 2022
- Messages
- 54
Center punch and drill out. Tough slow job.Removed the heads to unclog the passages and I broke a bolt. What are my options here?
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good idea never heard of that before. makes sense!The welded nut option works well. The heat from welding helps loosen it up as well.
If that fails put the head back on find a section of tubbing that fits the bolt hole in the head perfectly then a drill bit that fits the tubbing perfectly and that will get you a perfectly centered hole then you can drill the rest out.
Best of luck
Penetrating oil and a heat gun on and off for a week....There's several ways to skin this cat...
If it were me I'd take my Dremel and cut a slot in the bolt for a large screwdriver tip. I'd then knock off all the salty junk off around the screw. Then I'd douse it in penetrating oil and let it sit for a while. Eventually I'd use a large square shaft or bolstered screwdriver and wrench to hopefully break it free.
I this doesn't work out then I'd either use the drilling or welding method.
In this perticular spot you want to heat the bolt and let it cool over and over again.Well I spoke to the local boat yard and they seemed to think torching an aluminum block will damage it. Other guys on various forums all say otherwise. I also asked a mobile outboard mechanic who was onsite and he said heat and try to grip it with vice grips. I'm taking it to the local jack-of-all-trades-boat-guy on Monday. Each person I asked referred to him first saying "have you spoken to XXX?". He's competent and won't give up. Looks like I have several valid answers, thanks all.
Recap: I took it to a welding shop who said they could get it out. They tried welding a nut onto it etc but it was too brittle and kept breaking. So they drilled, punched, drilled, punched and used several grinding and drilling bits. Finally got through and they decided to run a tap into the threads in case any got boogered up. Tap went in just fine and when he went to remove it the tap broke off flush with the block! He wasn't applying much torque at all ... They ended up re-drilling and tapping the hole. Took them three days since they were working on it between major jobs. Now just waiting on the new thermostat seals and I can put them back on.In this perticular spot you want to heat the bolt and let it cool over and over again.
Letting someone more experienced do it is the right call. In the mean time getting it presoaked will save him some time.
Ouch, I broke an easy out once and it wouldn't drill out. Total disaster.Recap: I took it to a welding shop who said they could get it out. They tried welding a nut onto it etc but it was too brittle and kept breaking. So they drilled, punched, drilled, punched and used several grinding and drilling bits. Finally got through and they decided to run a tap into the threads in case any got boogered up. Tap went in just fine and when he went to remove it the tap broke off flush with the block! He wasn't applying much torque at all ... They ended up re-drilling and tapping the hole. Took them three days since they were working on it between major jobs. Now just waiting on the new thermostat seals and I can put them back on.
mercury casts an alloy in all there aluminum blocks so this problem never happens as aluminum corrodes and seizes any bolt so you were lucky to have only one broken - the best way for a pro repair, grind the top of the stud (broken bolt) so its pretty flat, center punch the center , using a small center drill drill the center not all the way , using smaller drill bits drill through the stud and no further you will feel it when it drills through the stud , next get the tap drill and drill through the stud, using a countersink or larger drill bit just use it to chamfer the radius of the new hole, basically just cleaning up the top of the hole then use a 3 flute taper tap same as your head bolts use some cool tool or cutting oil to aid in tapping and just a bit at a time in and out clearing away any chips ,i say use a 3 flute as the 4 flute taps bind up and may break , i cant stress enough take your time and if you dont have a drill press drill straight not crooked, dont weld anything to the existing stud as you may get into a bigger mess, when the tap starts to tighten up back it out air blow the hole to clean out metal chips and proceed until your through and done! a pro job!!Removed the heads to unclog the passages and I broke a bolt. What are my options here?
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