Stripped out accessory bracket thread
- Thread starter gentek10
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The biggest fail with thread inserts is the drilling of the hole before the insert is installed. That is easily botched. I prefer to start all taps with a rigid power source for the first few threads. It's easy to keep the tap straight. Then I usually finish tapping by hand if it's cast iron or stainless. I usually power right through aluminum though. You get better and better with thread inserts the more you use them. I often use a good pair of side cutters to cut coils off the insert to get the length I need.
turbofabricator
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- Mar 7, 2004
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One of the hardest issues with cheap thread repair kits is the coil insert tool. I use high dollar Heli-Coil kits on aircraft and never have an issue getting the insert started. They have an external mandrel that spaces the coil correctly. It makes a huge difference in ease of installation. Probably don't want to buy that style of kit to do just a couple of holes, though. The cheap sets available at most autoparts stores will usually work good. Getting the hole perfectly straight can be a challenge, and just getting the insert to thread in past 2-3 threds with out winding up the coil inside the hole can be tough. If you have access to a TIG welder, you could re-weld the bracket and then drill and tap the holes. Using a longer bolt and a nut on the back side is probably cheapest, though a pain to remove the pump in the future (you might need to grind/file/sand the backside of the bracket flat for the nut to rest against). I leave the pump on the bracket and pull it from the head when removing the engine or cylinder heads, anyway. Personally, I'd helicoil the bracket if the threads are bad. The factory should have done that from the get-go. I've had to helicoil ALL the holes in a bracket before. (some folks have a knack for killing threads.
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)I do if it's in aluminum. I use oil for cutting aluminum and just keep bumping the power switch till I'm down as far as I want to. Once you have a feel for it its very easy. I've likely done over 3000 heli-coils in my life. When I did a lot of early 4 speeds I was doing at least 10/week. F'in animals.
jskarateka
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- Nov 16, 2008
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- 139
To help with the pilot hole you can take a bolt the same size, put it upside down in a vise and drill through the center of the threaded end about a half inch. Then cut off that part and thread it in to the few threads that you have on the bracket. Now you can drill through both without the drill bit walking. This works well for instances when you can't put whatever the part is in a vise, or if the bolt is broken off at an angle.
groumoutis
Active Member
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- May 1, 2009
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If you can get to the back side of the bolt then you can center punch that side and use a normal drill bit instead a left hand bit to drill it out. I deal with broken bolts daily and some can be a pain and some are simple. The good thing about aluminum is that when heated it expands faster than steel so it shouldn't be too bad.
After thinking everything over and taking to account i dont have a press or helicoils or even extacters and then time it would take to get any of these things like bison said. And i didnt want to wait for a bracket to ship and throw away 40 bucks..i ended up putting the bracket in a vice and drilled out the bolt and drilled through the bracket .. Bought two four inch bolts a couple washers and nuts for 3 bucks .. Added some lock tight and that's that.. Simple clean and functional is how it ended up.. And Don't forget If later I want I can still weld and retap if I want to.. Thanks to all.
turbofabricator
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Glad that worked out for you.
