Broken bolts in the bellows housing

[dlogvine]

I'm replacing the bellows housing and transom plate for Alpha One Gen 2 outdrive. When I removed the v-pipe I saw that two bolts on the bottom were broken. When removing the trim sender, another bolt broke. Two of the V-pipe fastener bolts im planning on removing by welding a couple nuts on the top and using the impact driver to break the fusion. For the trim sender retainer bolt, i tried to remove it by drilling it out, but first the bolt extractor broke and then the drills started breaking like crazy. I managed to frill out about 1/2" hole that will fit the bolt, but the remainders of the bolt extractor or the bit were stripping the tap. I managed to get a thread strong enough to hold the bolt, but I wonder if there is a better way to fix it?
For the V-pipe bolts I think welding the nuts will heat up the bolts enough to break them lose, but I saw people using the 12V battery to heat up the bolts via current and break the fusion. Is it a feasible way?

 

[Bt Doctur]

With the motor out ,2 of the Y pipe bolts are broken in the transom housing? Trim sender and trim limit swith screws usually do just break and all you do is relocate the holes by redrilling and retapping them.

 

[dlogvine]

With the motor out ,2 of the Y pipe bolts are broken in the transom housing? Trim sender and trim limit swith screws usually do just break and all you do is relocate the holes by redrilling and retapping them.

Thank you, I tried to drill the trim sender unit hole in the same location and it was difficult because of the other screw. I was not sure if different screws location will affect the position and the functionality of the sender unit. Should I drill the holes as close to the old ones in 1/2" from the old locations or it does not matter much?
As for the Y-pipe bolts, the two on the bottom had broken heads. But they had about a 1/2 left of thread so im planning on welding a nut on the top of each and use the impact driver to remove them.

 

[Bt Doctur]

dosent matter where the holes are drilled, you reset the index center to match the new location.
Are you saying you have the housing aleady off ?welding may work ,maybe a HOT torch but can also make it flush, center drill , drill and retap to the correct size

 

[dlogvine]

I was switching the housing and outdrive from the old 1993 larson boat to a new 2005. So the housing is off the boat which makes the replair much easier to do. Will take it to our studio in community college tomorrow. They have a bunch of welders and I can use a TIG welder to do the job. If it wont work well, will use a hot torch or connect the tip of the bolt to the car battery with the second terminal of the battery connected to the housing as close to the stud as possible. Just need to watch to make sure aluminum housing wont start melting.

 

[Rick Stephens]

I would probably mig it instead of tig it. Stick a 3/8 nut over top and run the wire right down the middle. It goes really fast, plenty of heat to expand the broken off part of the bolt and free it up. Problem with tig is so slow you end up with too much heat on the aluminum. You only want the SS bolt hot.