First Time in Lower Unit - Broken Bolt

[stevedar]

Working on an Alpha One Gen II and trying to split the case on the lower unit to service the water pump, but the shorter bolt that ties them together from underneath near the pin in back has broken.

I've found some good links on how to take out a broken off bolt and if I don't have left hand drill screws I will buy them, but is there anything to watch out for or make the job easier? What about applying heat from a propane torch - good idea or not?

http://www.secondchancegarage.com/public/671.cfm

http://www.madelectrical.com/workshop/broken-bolts.shtml

 

[Bt Doctur]

Re: First Time in Lower Unit - Broken Bolt

Do you mean #66 http://mercstuff.com/fichef.htm

 

[stevedar]

Re: First Time in Lower Unit - Broken Bolt

Yes, sir, #66. I have the upper part of the stern drive upside down and that one didn't come out. My son broke it long after I went to bed, but I know it was very difficult to remove even with PB because I was holding the unit for him earlier in the evening and it just would not let go.

I haven't filed it down yet, so I still have a small "tab" near the edge to try the vice grips (which all my good tools are at the rental right now), but any other good "tricks" to get it out would help. Thinking about the one hyperlink, if it comes down to drilling it out with LH bits, I was hoping to drill a pilot hole with 1/8" bit and using a 1/4" bit with reverse threads to get it out? A little worried that my Harbor Freight corded electric drill will have the umph at low torque, but we shall see soon enough.

 

[Bt Doctur]

Re: First Time in Lower Unit - Broken Bolt

The Best way is to file it flat, center punch it , drill straight , going up in small increments so as not to break the drill bit untill you reach the correct size to re-thread it.