a bit of busted bolt repair info

grumpyvette

Administrator
Staff member
obst67 said:
Hey guys. I'm in a bit of a pickle. I am rebuilding my 350 out of the vette and one bolt hole from the oil pan is pretty mangled. I have no idea what happened because I never did this (previous owner). The hole was originally filled with puddly and a stud was stuck in it. It must have worked because it never leaked oil from that area.

Now my question is what is the best solution to fix this problem. It looks like the person who did it was trying to drill a hole and was no even close to being straight. If I took it to a machine shop could the drill a bigger hole and put a custom threaded sleeve in? Or are there better options. See my picture I attached.
busttr1.jpg

busttr2.jpg

Thank you

your almost sure to need a 90 degree drill to gain access to drill and use an easy out tool
be sure to accurately center punch the broken bolt before drilling it to use an easy out screw extractor
24936kl.jpg


https://www.harborfreight.com/spring-loaded-center-punch-621.html

81XZ.jpg

https://www.amazon.com/DEWALT-DCD74...636101&sr=8-1&keywords=dewalt+90+degree+drill


drillease.webp

https://www.amazon.com/Extractor-Ha...+bolt+extractor+set&psc=1&smid=A2O3U707GC6UX7


http://garage.grumpysperformance.co...studs-bolts-rusted-in-place.11410/#post-52306

http://garage.grumpysperformance.co...-of-busted-bolt-repair-info.11095/#post-49451

http://garage.grumpysperformance.com/index.php?threads/removing-rusted-broken-bolts.807/#post-43181
Bolthelicoilrp.jpg





the previous owner rather obviously tried to use a hand held drill and failed MISERABLY in the attempt to maintain the drill on the broken bolts center axis, but any decent machine shop
will have little problem removing the remaining threaded section of that bolts and repairing the threads with a helicoil kit.

its one of the reasons I purchased a milling machine, a repair like that generally requires a trip to a local machine shop where they throw the engine block up on the mill, secure it, level it, index the offending busted stud or bolt and center drill it then back the now hollow threaded remainder out with the correct tooling then use a helicoil kit to repair the threads, a job like that is not all that expensive, most machine shops will charge under $40-$60 but its a P.I.T.A. to transport the block, and go back the next day to pick it up or wait while its being done, and after running into several dozen little jobs that required a MILL, and having the skills and experience already personally to run a mill I got rather pissed off at myself for paying $40 here and $60 there on a regular basis for work that basically cost the machine shop pennies to do, (other than the salary of the guy doing the work) and said screw this, and bought a mill!
now I don,t expect most guys to go out and buy a mill, but having one is very helpful, so thats why a machine shop will generally have the mill and use it!
but at the same time I can,t see how any serious hobbyist won,t have a decent drill press in a home shop, and a few left hand twist drill bits and helicoil and easy out screw extractors


http://forum.grumpysperformance.com/viewtopic.php?f=27&t=4231&p=39800&hilit=milling+machine#p39800

viewtopic.php?f=27&t=1262&p=2712&hilit=taps+dies#p2712

viewtopic.php?f=27&t=4714&p=18266#p18266

viewtopic.php?f=27&t=970&p=1691#p1691

t20828.jpg


related info, LINKS AND VIDEOS THAT WILL BE VERY USEFUL

http://forum.grumpysperformance.com/viewtopic.php?f=59&t=807&p=1177#p1177

http://forum.grumpysperformance.com/viewtopic.php?f=50&t=729&p=1263&hilit=removing+busted#p1263

viewtopic.php?f=27&t=970&p=45483&hilit=drill+press#p45483
 
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