Broken Bolt Removal

littlebill31

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I should have done it when I thought about it, but noooooo, I waited.

I was doing a check and while removing the front brake master cylinder cover I snapped the head off of one of the bolts. I had planned to change them to stainless allen heads last time because the phillips slot was getting a little rounded. But I waited and this happened.

So my question to everyone is how to remove it? I bought new stainless M5 allen heads last night and changed 3, but the one that broke has broken a little less then flush with the reservoir, cover removed. There is nothing to grab the bolt with since it's down in there and I'm a little scared to drill because the reservoir is plastic. Buying a new reservoir is a little too pricey right now. Can I just use the 3 'till I can get a new one? Ideas?

Thanks all
 
Soak it with pb. Then take a small punch and small hammer and tap the top to back it out. Once enough is exposed you can take a pair of channels and grab it.

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probably deformed the thread right where it broke:doh: yeah try soaking it, you might want to look up reverse drill bits, even if you lose the top thread in the body should be enough to hold the cap cover with the others
 
That's tough one the stock screws are bevel head phillips how well are the allen heads going to work/look? Plus one on the pb blaster and time. I wouldn't run just three if I had any good paint nearby. I feel your pain that is a small diameter bolt, I guess I would try a very small drill bit in a hand held drill and try to finesse keeping it centered. Normally if the bolts were that rusty the whole brake system is overdue for an R&R anyways. Unless you are very patient, skilled, and trusting in your work, a replacement m/c makes a lot of sense.
 
Actually the allens are beveled as well. I put 3 in and they worked perfect. Got 'em from Ace hardware.
I flushed the brake fluid out a month or so ago, new pads, cleaned them up. The system looks really good too. The bolts weren't even rusty. Just popped clean off. The bolts do go through a captured hole. Kinda self contained from the actual fluid.
Guess I'll try to work it out. I did spill fluid every where when I popped the head off. It was the last bolt I took out and when it popped the cover came off. Rags and stuff went a flyin' to clean it up. Only hit the rear of the front fender, which is about to be stripped and painted.
Thanks for all the help.
 
Good that the system was cleaned. bevel Allen heads should look very nice. Sorry if you did this but i have to ask: Did you pull the pistons and seals out of the master cylinder and caliper? It isn't a brake job if you don't.
 
LOL, no I did not. The bike had 9800 on the clock when I got it. I changed everything I was unsure of when I got it. I don't believe, "oh, I just changed..." from a PO. I plan to get a new master soon and do the rest. The system had very good looking fluid come out when I changed it, no grime or junk in it, and NO, 2 different types of fluid in it thank goodness. The rubber is very pliable and was all good as a whole. It works great and no leaks.
 
Trust me on this, pull them and the seals. I guarantee there is a wad of crap under the caliper seal. Odds of a rusty piston are way up there too. Really I am not trying to be a jerk but I have R&Red at least 30 XS650 calipers, I have two bus tubs full of parts, I have yet to open one up that didn't "need" cleaning. And this includes several <10K rust free bikes. They are all 30 years old.
 
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Oh I don't think you're being a jerk. That's why I'm on this forum, to get good advice. I am going to clean them as soon as I get a full damn day off. I'm trying to get as much done, work wise, during crappy weather so I have time to enjoy the good days.
 
I had the exact same thing happen to me. I replaced mine with allen heads and they have been much better. No more stripping!

Anyways I just stripped mine, thankfully it wasn't broken. I think I eventually got it out with an impact driver. Seriously though everyone should replace the stock phillips head screws on your master cylinder. They are almost guaranteed to strip eventually.
 
I just changed out the old rubber hose on My front brake to a braided stainless.
even though I know better, I tried to lok the other way when the dirty fluid dribbled out into the pan. I tried to look the other way when I saw how dirty the fluid was in the reservoir. I know better. Now, before the bike goes back on the street, it will have rebuilt caliper and new master cylinder. Sadly, yesterday, I had to put 4 new shocks and 4 new Goodyears on My pickup. That was the paint/upgrades budget for My XS. I wish a sack of money would fall from the sky.:( BTW, the ugly yellow seen in My avatar pic is going to become a metallic gray, with flat black stripes.
 
I usually try to cut a screw slot in what's left, using a Dremel. Also, does the plastic reservoir detach so you could get to the screw? It's got to be put on there somehow and I doubt it's glued.

Pyroman, leave it yellow. It looks great.
 
The screw goes thru the reservoir and into the threaded bottom part of the master. Which is a solid piece. I tried that, but it wouldn't come off. I don' want brake it more LOL
 
I have the same cyl. What holds the plastic reservoir to the metal? I never looked.
 
the plastic part is held in/sealed by a big honk'in o-ring it can be removed but usually needs to be turned sideways to do it
 
If you can get it off, then use le vicegrips to get screw out. Put le reservoir back with "Automotive Goop" or one of the other Amazing Goop products (I think they're all the same stuff).

P.S. I would probably try a knife blade for a wedge with a little hammer to try to get it to start separating....
 
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That's just delaying the inevitable enlèvement du réservoir.
 
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