1993 Yamaha lowerunit bolts HELP PLEASE

[hurricane34]

Got a saltwater motor.Trying to take the lowerunit off in the process two bolts broke off on the right if you are facing the motor.The first and last bolt broke off.The bolts broke off at the threads in the hole.No what any help would be greatly appreciated I did a search but am a little confused on what to do.I did heat the bolts up and use pb stuff from autozone worked on all but two of course.I know maintenance would have prevented this but i just got the motor.Any help would be greatly appreciated thanks.

 

[rodbolt]

Re: 1993 Yamaha lowerunit bolts HELP PLEASE

finnish removing the unit and drill and tap or heli coil the broken studs, I use oxy/acetylyne and heat the midsection hot enough to pull the thread out with the bolt and heli-coil the hole. but I have delt with saltwater a long long time.
for drilling try to use a bullit point type drill and start with the tap drill size, works eaiser.

 

[hurricane34]

Re: 1993 Yamaha lowerunit bolts HELP PLEASE

You say finish removing the unit.What do you mean by that?There no other way to get to drop down with out drill and tapping the holes right?Besides heating it up that I dont know how to do and dont want to do that.

 

[mikesea]

Re: 1993 Yamaha lowerunit bolts HELP PLEASE

It depends on where the bolts actually broke.If part of the bolt is still in the lower unit housing you may need to heat the area round where the bolts are stuck and tap the unit down CAREFULLY not to breal any aluminium plates.If ALL bolts are removed and the bolts broke off as they enter the midsection(part abvoe the lower unit)the lower should drop.Did you remove all bolts"dont know you hp,but on the underside of the lowerunits there are other mounting bolts ,even UNDER the trom fin ,(the little triangular piece,on larger engines that is removable from the top,there may be a rubber plus that is also triangular,pop that off and you will find a 13 mm bolthead under it.But it seems like you may need to bring it to a shop.You will need to drill out the remaining bolts pieces.I like to use COBALT bits,starting small ,drilling center of bolt and going up in size to closest to bolt dia.Then I use a reverse bit,running my drill in reverse OFTEN causes the last bit of thread from the bolt to drill out.then follow with an appropriate tap.

 

[hurricane34]

Re: 1993 Yamaha lowerunit bolts HELP PLEASE

Got one of the bolts out.I was wondering if it was ok to run without one of the 7 boths that go on the side there three on each side one under trim tab.The one I would run with out is closes to you if standing in front of the motor on the right side.

 

[rodbolt]

Re: 1993 Yamaha lowerunit bolts HELP PLEASE

if 6 wont hold it 7 is meaningless, but if the unit is off its just to simple to eaither heat it or drill it, pay no attention to the above post about over heating, your heating a very large heat sink. if you actually start to melt the housing simply move the flame away and it quits melting immediatly, cause your heating a heat sink.
work with junk saltwater motors for 30 years and smoke dont scare you, in fact it becomes your friend .