I was replacing my oil pan and I must've crossthreaded one of the oil pan bolts by not properly lining up one of the holes in the gasket when torquing it down. The bolt head sheared off and now half the bolt is embedded in the block. What can I use to get it out? This is on a motorcycle btw, the bolt is real tiny (8mm).

6/11/2008 1:00:45 AM

It would be good if you could notch it somehow and remove it with a flathead screwdriver. Since you have such little surface area and it isn't protruding it's going to be tough though. Maybe it would work if you take a a dremel tool with a small diamond bit and just carefully cut a notch across it.

6/11/2008 1:18:49 AM

you will need a extractor bit to dig into the bolt. then an extractor and an open ended wrench. i have plenty of extractor bits. i found that its best at high speeds from a dremel or air tool.

http://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2547&page=1ꁙ

6/11/2008 1:26:19 AM

an extractor aint gonna do shit on a cross threaded or rusty bolt, and drilling out a steel bolt in an aluminum bolt is damn near impossible even in a milling machine

6/11/2008 9:34:52 AM

how bout a solution to the problem then.

6/11/2008 9:54:09 AM

Center punch, then drill ON CENTER with the biggest bit that fits inside the thread's inner diameter.

It's best to use a cobalt or carbide-tipped bit, drill slowly, and use plenty of lube on the bit. Even better is a left-handed bit of the aforementioned type(s). Both types of bits tend to be more brittle than your average black steel/HSS bit, so be careful. Dremel makes a carbide mill bit that works wonders on machining away screw remnants, and I've plunged a thermostat housing bolt that sheared entirely with that puppy (and I had broken off a cobalt bit in the damn thing). Helicoiled it and was good to go.

Then, use a screw extractor to try and back it out. The threads are gonna be FUBARed anyway, so get yourself a Helicoil kit to fit and the appropriate drill bit to drill the hole to the recommended size before tapping and inserting the Helicoil.

[Edited on June 11, 2008 at 10:02 AM. Reason : blahblahblah]

6/11/2008 10:01:10 AM

^ yep


problem is that if that if the bolt is not in there straight, it's impossible to drill it and not fuck up the threads worse, in short, you got a good project there

your other option is to put plenty of silicone in the gasket in that area and just tighten up the rest of the bolts

6/11/2008 10:17:52 AM

Quote :

"Even better is a left-handed bit of the aforementioned type"

Or take it to Hamiltons machine shop and have them fix it.

6/11/2008 12:09:39 PM

this kind of shit is how 4 hour installs turn into 4 week installs

6/11/2008 5:41:05 PM