Author Topic: 550 Head removal - snapped head off the front 6mm flange bolt...  (Read 846 times)

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Offline SpindleHausen

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...And now the head is stuck on by one rather stubborn bolt with very little room to get at it. The head is sheered off at the top, leaving the log exposed body intact, but I can't see anywhere to get a grip onto it to remove. I'd hoped that although the bold head had sheered off, the head would come away anyway, as the threaded part is in the barrel (or so I thought) but it won't move.

Any ideas?

thanks

-pete
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Offline flybox1

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Re: 550 Head removal - snapped head off the front 6mm flange bolt...
« Reply #1 on: May 06, 2013, 10:21:30 AM »
pictures always help  ;)
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Offline dave500

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Re: 550 Head removal - snapped head off the front 6mm flange bolt...
« Reply #2 on: May 06, 2013, 12:37:08 PM »
you might have missed another nut?there is also a 6mm bolt at the rear.

Offline SpindleHausen

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Re: 550 Head removal - snapped head off the front 6mm flange bolt...
« Reply #3 on: May 06, 2013, 03:06:14 PM »
Got that one thanks - under the cam chain tensioner top mount bolt. Update is that the head now moves relative to the barrel, but the broken front stud seems to be threaded in both the head and the barrel, so is still under tension. In case it is just corrosion holding it in place I've left it lathered in WD40 (potted mechanic) in the hope it frees off...

Will post a photo tomorrow (or when I find the right USB lead
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Offline Fritz

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Re: 550 Head removal - snapped head off the front 6mm flange bolt...
« Reply #4 on: May 06, 2013, 03:11:24 PM »
There's no thread in the cylinder head. Otherwise you would not be able press down the head onto the barrels when you put it back on.
Probably, the head gasket is just sticking, so be patient and take care of those fins :) A heat gun might help...

1976 CB550F

Offline SpindleHausen

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Re: 550 Head removal - snapped head off the front 6mm flange bolt...
« Reply #5 on: May 06, 2013, 03:23:19 PM »
cheers Fritz, I was just thinking that both pieces can't be threaded, as the factory would never have been able to cut the thread in one pass. Will leave it in WD40 and get some more heat on it in the week after work.

-p
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Offline crazypj

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Re: 550 Head removal - snapped head off the front 6mm flange bolt...
« Reply #6 on: May 06, 2013, 04:09:58 PM »
Corrosion is pretty common, you'll just have to work at it for a while.
Don't lever at it, too much chance of breaking something.
Couple of wood 'shims' between cylinder/block to wedge things apart may help?
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