by Brit-Car-Nut » Thu 28.11.2013, 15:25
Pete: Usually crush washers are reusable but sometimes they aren't. If they have "crush" indentations on either side, it is best to replace. If they are nice and smooth, then reuse. Torque the banjo bolts to the proper spec.
There are pages of advice available to suggest the best way to drill out a bolt, but the most important bit of advice I can offer is to try to get the drilling surface as flat as possible and try to carefully find the center. Use a center punch to give your pilot drill bit a good place to start from. Work out the best way to hold the drill to keep it in line with the bolt's direction or angle. Use a lot of lube to keep the drill bit cool. Start small and slowly work up in diameter until you are able to get a good "bite" on the bolt and remove it. It is really hard to get exactly in the center, so watch your hole size because one area will eventually drill into the threads and that causes other repair work.
I don't know how common they are in the UK, but I use LH turning bits once I get my starting hole drilled. If you are removing an 8mm bolt, you can use any drill up to around 3mm but then start using LH bits because it is possible that at some point, as the center gets drilled away, the bolt will break free and turn out with the drill bit.
You might consider posting a picture of the work area. Someone else might have had to do the same task and might be able to provide specific hints, tips or warnings from their adventure.
When it comes to removing stuborn hardware, heat is often a big help. You often see or hear the phrase heat wrench. A well placed torch along with good penetrating fluid are a mechanic's best friend.
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