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Broken valve cover screw

Bob Boro

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My left lower valve cover screw snapped while screwing it back into the right cylinder. It had not bottomed out when it snapped. Maybe 2/3 of the way in? What is the best way to remove the screw? It snapped flush with the surface so there is nothing grab onto. Easy out? Some other kind of screw removal devise? Drill it out? Suggestions? Thanks! 2003 R1150RT.

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Morning Bob


That is not a difficult removal IF you are familiar with the process & have the correct tools & know-how.


On the other hand it is ever so easy to make the problem worse if not done correctly with great precision.


I will suggest that you NOT use or try to use an easy-out as those things are mis-named & should really be called an easily-broken-off. Once an easy-out snaps off then you have real problems. They (easy-outs also expand the broken bolt in the threads making it more difficulty to get the broken piece out.


I would have to look at the broken piece remaining to make an informed decision but the usual way I get those broken-flush bolts out is to: clean the broken bolt of all oil, then place a thin washer over the broken bolt & NEATLY weld the washer center hole to the broken bolt, then neatly weld a nut to the thin washer. Then as it is cooling back the broken bolt out using that welded on nut. The heat expands & loosens the broken piece & they usually come right out.


Other options are to drill the broken bolt piece out using a series of LEFT HAND drill bits. Start with a small center drill then once the hole is EXACTLY CENTERED start increasing the L/H drill bit size until the broken piece is drilled out to thread diameter. If done correctly one of the larger L/H drill bits will catch in the broken bolt & spin it right out.


There are other methods but the two mentioned above are usually the best & least apt to create further issues.


My best suggestion is to have that broken piece removed by a person familiar with flush broken bolt removal. If done correctly it will probably come right out, if done incorrectly it will become very difficult to remove & could leave the threads damaged or the hole off-center.


If you can post a (CLEAR close up) picture of the broken bolt in the head then we can maybe offer other options to you.


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If you go the "drill it out" path, I have found that a Dremel tool is handy for creating a flat, or even slightly concave, surface to help with getting that starter drill hole centered.


Whatever route you go, be sure to generously protect the surrounding sealing surfaces of the head, just in case.

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If you do go down the 'drill it out' route, it is worth making a jig so that you are drilling dead center and co-axially with the bolt hole.

Also, a left hand spiral drill may be a godsend. This action tries to unscrew the bolt as it drills.

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