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A sharp AWL and some patience or even a pencil ERASER and some patience many unscrew the broken stub.

I'll suggest to NOT USE any RH rotation drill bit on it! Purchase a set of LH drill bits if the above tips are un-successful.

The threads should be 'perfectly fine'. JUST Don't bugger up the exposed aluminum above the broken stub!!!!!
 

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Sorry to see that dutchman, but it was certainly no surprise.

The good news is that your dutchman is not preloaded, so it should be fairly easy to remove. However, take no short cuts when preparing for its removal. If it were me I would first take a Dremel tool with a small globe-shaped stone and make a dimple about 1/16" deep in the center of the broken face of the dutchman. Then using a hammer and a sharp prick punch make a sharp dimple in the center of the previously made dimple. Next using an appropriately sized drill bit for the "Easyout" you selected, drill a hole using the prick punch dimple as a centering guide. Insert the Easyout into the hole you just drilled and give it a light tap with a hammer. Lastly, using a wrench, start rotating the Easyout to the left and the dutchman should come right out.

I would then drill, tap and install a Hellicoil sized to match the thread on the valve cover bolt. Obviously you'll need to buy an new bolt from Kawasaki. Lastly, I would buy new sealing washers for the valve cover bolts, and perhaps a new valve cover gasket.

Of course before grinding, drilling and tapping, you need to take whatever means necessary to keep debris out of the head. Probably stuff some rags around the area you will be working on.

Jason
 

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Well, I guess Paul was responding while I was typing my response.

I'm not sure why a right-hand drill bit would be a bad thing.

And I would take no chances with the threads, as I feel confident they have been compromised. A Helicoil repair is not too expensive or difficult and produces quality results, so why not do it?

Jason
 

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A right hand drill bit may snag and screw the stub IN farther & Harder. A Left hand drill bit may snag & simply un-screw the stub.

I'm confident that the original threads are NOT compromised, otherwise the stub wouldn't have broken, the threads would have stripped.

The sealing washers & valve cover gasket need to be torqued to a Mere 60-70 INCH pounds, or just snug. The elasticity & grip of the rubber parts keeps the bolts from backing out.
 

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Sorry to see that dutchman, but it was certainly no surprise.

The good news is that your dutchman is not preloaded, so it should be fairly easy to remove. However, take no short cuts when preparing for its removal. If it were me I would first take a Dremel tool with a small globe-shaped stone and make a dimple about 1/16" deep in the center of the broken face of the dutchman. Then using a hammer and a sharp prick punch make a sharp dimple in the center of the previously made dimple. Next using an appropriately sized drill bit for the "Easyout" you selected, drill a hole using the prick punch dimple as a centering guide. Insert the Easyout into the hole you just drilled and give it a light tap with a hammer. Lastly, using a wrench, start rotating the Easyout to the left and the dutchman should come right out.

I would then drill, tap and install a Hellicoil sized to match the thread on the valve cover bolt. Obviously you'll need to buy an new bolt from Kawasaki. Lastly, I would buy new sealing washers for the valve cover bolts, and perhaps a new valve cover gasket.

Of course before grinding, drilling and tapping, you need to take whatever means necessary to keep debris out of the head. Probably stuff some rags around the area you will be working on.

Jason
There is a good chance that now that the bolt is not under load it will turn out with very little torque. Using your center dimpling suggestion and the left handed drill bit that pdwestman suggested the bolt will likely come out with the torque from the left handed bit biting in as it cuts down. It might even come out by tapping counter clockwise with a sharp punch.
 

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A right hand drill bit may snag and screw the stub IN farther & Harder. A Left hand drill bit may snag & simply un-screw the stub.

I'm confident that the original threads are NOT compromised, otherwise the stub wouldn't have broken, the threads would have stripped.
The torque via a right-hand drill bit is negligible. The most important aspect of drilling ANY hole in the dutchman is to make damn sure it's in the center, hence my two-step process.

Regarding the condition of the threads, I typically see the threads at this particular location stripped rather than the bolt twisted apart. Seeing the broken bolt highly suggests that the female threads have been subjected to stresses beyond the yield strength of the relatively soft aluminum material. So why take a chance on trying to re-use them when it's easy to make a quality repair?

Jason
 

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There is a good chance that now that the bolt is not under load it will turn out with very little torque. Using your center dimpling suggestion and the left handed drill bit that pdwestman suggested the bolt will likely come out with the torque from the left handed bit biting in as it cuts down. It might even come out by tapping counter clockwise with a sharp punch.
Maybe a left-hand drill bit will work, but a person should be able to come up with an easyout and right-hand drill bit quicker than a left-hand drill bit. So why not?

I can see I'm swatting at an empty pinata here, so I'm through with this discussion. :SadSigh:

Jason
 

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Maybe a left-hand drill bit will work, but a person should be able to come up with an easyout and right-hand drill bit quicker than a left-hand drill bit. So why not?

I can see I'm swatting at an empty pinata here, so I'm through with this discussion. :SadSigh:

Jason
I see your point. The bolt is likely bottomed out already and either bit would get the job done and easy-outs are easier to find than left handed bits. So it is an owner's choice.
 

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The broken stub really should NOT be bottomed out. And we do NOT want to 'jam' it in by using a RH drill bit.

I should have suggested the pencil eraser FIRST! Then the sharp awl. Then the LH drill bit. Then the easy out, which is never 'easy'!

And I'm trying to prevent having to use rags & vacuum cleaner & drills and untold time to fix what may be a Very SIMPLE problem, if approached with care & forethought.
 

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Discussion Starter #31 (Edited)
I very much appreciate EVERYONE'S thoughts and suggestions. I called the local dealer to see if they had a bolt in stock. Of course, since it was late afternoon Saturday and they're closed Sunday and Monday, they don't have one but will gladly order one for me - when they reopen on Tuesday. So I may get back to the broken bolt tomorrow or later during the week since the new bolt won't be arriving until Friday or Saturday. :mad0235:
 

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Discussion Starter #33 (Edited)
Took some pics of both right side valve cover bolt studs. I was prompted to do this because Norton 850 thought my original pic of the broken off bolt-in stud looked like it was possibly stuck in an insert (i.e., a previous thread repair). The first pic below is the right rear stud and, if that's a thread repair insert, it is well off center and has a peculiar spiral pattern on the top. The second pic is of the right front stud (the one that has become the subject of this thread). By the way, the right front stud insert that we've been talking about is flush with the base metal.

1. Can anyone confirm that the right side valve cover bolt studs do not come from the factory like this?

2. Assuming these are steel inserts, I think we now know how the bolt was broken off as opposed to the female threads just stripping out. Does anyone recognize what kind of inserts these are?

3. Again, assuming these are steel inserts, are there any changes to the earlier suggestions on getting the broken bolt out - now that we know steel is gripping steel? Use penetrating oil? Or don't?

Once I get it out, I'll hopefully be able to look within the stud/insert and see if there's something in the bottom that prevented the broken bolt from tightening all the way down. By the way, the right front stud "insert" is flush with the top of the aluminum stud. But there is a very slight height difference with the rear left insert vs stud.
 

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Schoen, I'm sure that those are NOT inserts into either of those stud towers. That is only the pattern of the flat base of the special, stepped oem bolts.

Just use a magnet on the un-damaged aluminum tower to confirm or refute my suggestion. And then the tower with broken steel stub.
 

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Discussion Starter #35
Schoen, I'm sure that those are NOT inserts into either of those stud towers. That is only the pattern of the flat base of the special, stepped oem bolts.

Just use a magnet on the un-damaged aluminum tower to confirm or refute my suggestion. And then the tower with broken steel stub.
:sign0161: Should have thought of that one all on my own.
The only thing the magnet sticks to is the broken off bolt.
 

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Have you noticed the oil drain hole near that mounting tower?

It drains camshaft oil past the valve springs & stems and down thru the cam chain tunnel to the balancer chain & sprockets, crank bearing & flywheel. I would suggest plugging it with a cork before any drilling.

I would secure a vacuum cleaner hose very close to the tower to suck up as much chips as possible while drilling.

Are you certain that a pencil eraser or sharp awl can't turn the broken stub at all?

I would use an 1/8th" LH drill bit if I had to resort to drilling.
 

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Discussion Starter #38 (Edited)
Have you noticed the oil drain hole near that mounting tower?...I would suggest plugging it with a cork before any drilling.

I would secure a vacuum cleaner hose very close to the tower to suck up as much chips as possible while drilling.

Are you certain that a pencil eraser or sharp awl can't turn the broken stub at all?

I would use an 1/8th" LH drill bit if I had to resort to drilling.
1. I didn't have a cork, but do sleep with earplugs at night. One of those worked.
2. Since my vacuum wanted to suck up my rags, I placed a magnet right near where I was drilling. That seemed to catch about 99% of the filings.
3. Triple checked with the eraser and sharp awl - wouldn't budge it.
4. Started with Norton 850's suggestion, using a very small rounded Dremel bit to carve out a small concave area, then hit the center of that with a sharp punch to indent and prepare for drilling (if at this point I had thought to quadruple check with an eraser or sharp awl, I might have gotten a different result - because of the whack I gave it). Then started drilling with a LH 1/16 drill (the bolt is very hard metal), and moved up to a LH 5/64 drill which eventually "snagged" and started backing out the broken bolt. I was doing all that to prepare to use the extractor bit (harbor freight's version of an EasyOut). Didn't have to.
 

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Discussion Starter #39
I ran the good bolt into the threads, they seem to function about the same as the rear threads (right rear stud tower). It also firmly seats against the top of the stud. So, still not sure how/why it broke where it broke. Waiting for new bolt. To be safe, I also ordered all new bolt gaskets and valve cover gasket.
 

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I ran the good bolt into the threads, they seem to function about the same as the rear threads (right rear stud tower). It also firmly seats against the top of the stud. So, still not sure how/why it broke where it broke. Waiting for new bolt. To be safe, I also ordered all new bolt gaskets and valve cover gasket.
Glad that it is "outta' there"!!

I think that too many people forget to re-set their 1/4 drive inch pound torque wrench from 106 in lb for the cam bearing caps, down to 60 - 70 in lb for the valve cover bolts. ;)

And I wish that the valve cover bolts were only 10mm hex heads so I wouldn't have to change sockets and to encourage a 'gentler hand' by those that don't/won't use a torque wrench.

I would only use either contact cement or RTV sparingly in the groove of the valve cover to retain the gasket.
I do NOT use any RTV on the head to gasket surface, not even at the half-moons or "eye-balls". And have never had a leak, with a pliable gasket.
 
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