I knew I would screw something up

[SeaKing15hp]

I posted in the past that I was going to replace a lower unit on a 1969 Evinrude 18hp Fastwin. Well, when the time came to do it, all was good until I snapped one of the 1/4-20 stainless bolts off in the cast aluminum leg. Luckily, I was able to complete the rest of my little project without a problem. I believe that I will be ok running this weekend with it broken, but how should I get this bolt replaced?? I have thought about having a buddy AC (I think) tig a nut onto it, since it is a pretty flush break, and just twist it out. I have done this before on cast iron and steel, but I am afraid that the aluminum will melt. Right now, the only way I can think of getting it out would be having some luck with an easy out. Has anyone ever been in this situation?? How should I go about fixing this? <br /><br />Thanks!<br />-Jacob

 

[R.Johnson]

Re: I knew I would screw something up

What ever you do, don't try an easy-out. Here is one way I do it, but it require's the use of a lathe. I make up what is called a drill bushing. With the gearcase held in place with the remaining bolts, a bushing is made up that would be a tight fit in the hole of the gearcase where the broken bolt went in. This bushing would have a 3/16" hole drilled through it. This bushing will guide the drill down the center of the broken bolt. The bolt then can be drilled out the rest of the way until just the threads remain which can be cleaned out with a tap. I removed two broken head bolts this way just last week. You will need a right angle drill, or die grinder to have enough room with the gearcase in place. Let us know what tool's you have, I can probably help you out.That bushing only takes a few minute's to make.

 

[G DANE]

Re: I knew I would screw something up

The welding method it far the best in my opinion, I've done this dosins of times. Use TIG weld. The heat will expand the rust and to now I never tried a bolt that didnt just turn out after cool-down. The flame doesnt seek the aluminium at all, I've sone some that were slightly under surface too.

 

[SeaKing15hp]

Re: I knew I would screw something up

My options are pretty much enless as far as tools go. I have even done a little lathe work my self in the past, although I dont have one right now. I think that I will try to have a nut welded on. The guy that I bought my motor off of (my buddy)runs a metal fabrication shop, and I may just pay him to weld a stainless nut on it. I figure as long as the heat doesnt melt the aluminum, it will help it to come out easier too. Thanks, G Dane for letting me know that it wont hurt the aluminum. <br /><br />Thanks!<br />-Jacob

 

[rodbolt]

Re: I knew I would screw something up

you will be amazed how much heat that heat sink will take. here in the salt pond oxy/acetylene is part of the removal procedure on a daily basis.<br /> the weld a nut on trick usually works but for 1/4 20 bolts I just use a drill and a bullit point 7/32 bit and drill them out. its faster than setting up a welder.