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1974 Johnson 15 hp Removing broken bolts

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Bullie

Regular Contributor
When I was removing the LU one side of the bolts broke off. What is my best course of action to remove them?


Also the cooling system is full of dirt dauber nests. Best way to get them out? Already removed these but they are in the upper vents too.
 
Before the first one broke you should have used heat !-----------Now use plenty of heat from a propane torch to heat the area around the 2 that are sticking out.------Then when hot use a vicegrip to get them out.
 
I'm learning. Not a mistake that I will ever want to repeat. These were the first ones i have ever had a problem with...not that there have been many.

There are actually 3 of them. The one on top doesn't have a lot of bolt protruding. Should I replace all 6 bolts? I have a good local hardware store with an excellent assortment of bolts. Are these common enough that I could likely purchase them at a hardware store or are they some special thread?
 
Yes I can count !! ---------That one will likely need to be drilled out --------Use 1/4-20 stainless as replacements.
 
Use Seafoam Deep Creep or PB blaster. Spray them liberally and let it soak in for a day if you have the time. After the soak use the torch to heat and vicegrips to get out or better yet a stud extracor. For the one that is broken off flush again use heat after the seafom soak and use a twist in style bolt extractor (you will have to center and drill into the bolt) the extractor you use will specify the proper size drill bit you use. Good Luck :)
 
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I have a MAC tools set I use. I have always used the proper size and have neve had one break. I wouldnt go buy something made in Tiawan.mac.jpg
 
Well, I am officially screwed then. I got the center one out. Before I read any of this I bought the easy out things and all I succeeded in doing was making a smooth hole in the lower hole and breaking a drill bit off in the upper one. How screwed am I?
 
Can you post another pic? What ez out did you buy? You may be able to still use a carbide drill bit and some cutting oil to drill out the one you broke. Is it centered atleast?
 
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Deano27, I think the kit I bought was made by Irwin...four different sizes.

#1 Bolt This is the one with the bit broken off in the top. Approximately 1/4 inch of bit maybe.


#2 Bolt Drilled completely through. I am not certain but I don't think, at this point, that I screwed so off center that I got the threads in the casting. Some of what you see there at the top are threads from the bolt that I pried loose from the side.
 
With all due respect to the guys that like their screw extractors, if the bolt itself wasn't strong enough to come out without breaking, how do you expect the smaller easy out to get it out? OK, I've said my piece on that, and back to the problem. A drill bit normally will not drill another drill bit (or easy out). What I'd do to save that situation is grind away the aluminum alongside the broken bolt, remove the bolt sideways through the ground slot you made, then take it to a qualified aluminum welder to fill in the slot. Then redrill and tap the hole.
 
fdrgator said:
With all due respect to the guys that like their screw extractors, if the bolt itself wasn't strong enough to come out without breaking, how do you expect the smaller easy out to get it out? OK, I've said my piece on that, and back to the problem. A drill bit normally will not drill another drill bit (or easy out). What I'd do to save that situation is grind away the aluminum alongside the broken bolt, remove the bolt sideways through the ground slot you made, then take it to a qualified aluminum welder to fill in the slot. Then redrill and tap the hole.
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The extractors are much harder than the bolt and they usually work well if you get them centered and use the right size :D

Anyway, At this point I would personally just stop and take it to a Respected machine shop to see what they can do, They deal with this kind of stuff and can hopefully fix her back up for you.
 
Having removed hundreds of sheared bolts from aircraft, I wouldn't go near an e-z out.

Having a large selection of machine tools, if I had to do it by hand I'd set-up a drill jig with drill bushing and face the bolt with an HSS end mill followed by a drill and Heli-coil combo. That assumes having the correct hand tools.

A decent drill press, part clamped to press and a series of drills (start very small to establish a center) should be an easy operation, again I'd Helicoil it.
 
I have learned a lot about what to do. I need to add a drill press to my tools. I probably would not have broken the bit off had I been using a drill press...probably. I appreciate all the information about what to do next time.

I do have another question on this topic. What do you guys do when you reinstall the bolts in holes that obviously had a good deal of corrosion or a broken bolt? Do you apply some type of anti-seize or grease/oil to the new bolts?
 
Remain calm - not a big deal.

#1 in the future, MAP (or oxy if you know enough to use it), goes a long way

#2 in the future it helps greatly to shock a bolt out and never to torque them when they are stuck. Regardless of the heat - tap the bolt and around it a little with a hammer if you think it's stuck, helps free up corrosion, then when actually trying to turn it use air tools or tap the wrench to turn the bolt. You want to shock it out an 1/8 turn at a time, not by increasing the torque. Sometimes if they start turning they jam later and you need to tighten them back down to free the corrosion. Try to always turn it very square in the process, twisting off center always breaks them.

As far as where you are at now - lots of options -

#1 - use a bigger bolt, re-drill to tap size and re tap
#2 - weld the hole to fill it and re drill and tap it
#3 - grind out that area and weld or bolt in a piece of aluminum stock similarly as #2
#4 - if you were insanely proud of the engine, find a replacement exhaust housing, would not be much $$ on Ebay but I bet you break lots more bolts trying to replace that :)
 
Oh as far as getting the bit out - usually with a hole punch you can smash up a drill bit and using a pick take it out in pieces.

On the anti-seize, I like white thread sealant. I use it on lots of things that do not call for any sort of seal, it seals the water out and the nature of it prevents seizing.

Jon
 
Had a similar problem with the exhaust to block bolts on a 15hp. Drilled the center, then upped bit size and ended up helli coiling. Not perfectly central but did the job. S/S is a bugger to drill out of ali though. Drill press helps.
 
poida said:
Had a similar problem with the exhaust to block bolts on a 15hp. Drilled the center, then upped bit size and ended up helli coiling. Not perfectly central but did the job. S/S is a bugger to drill out of ali though. Drill press helps.
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A good sharp cobalt bit will actually move through it fairly fast. Something important though is the correct speed/pressure (slow/moderate) and keeping bits properly lubricated - something as simple as keeping the speed slow and squirting some oil in there from time to time makes it go a lot easier. A drill press is nice for speed/pressure control and to drill straight, but can snap bits just as easily since they are harder to shut off if the bit should catch on it's way through the backside of the bolt.

The typical novice gets frustrated and holds the drill wide open while pushing too hard, which slows progress and tends to destroy the bit - making it seem like an impossible/endless task. Doing it the right way it's not really that hard.

With this type of project I'd start with having a few bits of the same size on hand for the initial hole, somewhere around 1/8 or a little bigger (bigger bits harder to snap but drill slower). You want standard point drill bits for this, not the ones with the centering point on them, as they do not allow stepping up to a larger bit easily. Additionally since it does take some time, you will want a regular corded 110 volt drill and not something with batteries.
 
How would you use a drill press on this particular job ???-----Shop will likely slice the housing.-----Pull the bolt out sideways.------Fill cavity by welding.---Redrill and tap to be like new.
 
racerone said:
How would you use a drill press on this particular job ???-----Shop will likely slice the housing.-----Pull the bolt out sideways.------Fill cavity by welding.---Redrill and tap to be like new.
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Haha good question :) - maybe folks are thinking you could remove the table on the press and secure the engine upside-down. I guess that could be done, I'd just use a drill; even with a part that fits in the press I would likely switch to the hand drill once I got an initial hole going.
 
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