Author Topic: CB550 rocker cover screws  (Read 2002 times)

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Offline separatist

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CB550 rocker cover screws
« on: November 28, 2015, 01:23:31 PM »
Okay, cracking open a CB550 engine after 41 years. Are these machines great or what? Anyway, I've successfully removed the rocker cover bolts and 6 of the 8 screws. The other two... I just can't get them, leaning with all my weight over the ratchet, turning gently, full body turn... they just won't go and are in danger of being fully stripped. Options? Cut a notch? I hate to drill...


Offline minimo

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Re: CB550 rocker cover screws
« Reply #1 on: November 28, 2015, 01:47:30 PM »
Have you tried soaking them with PB Blaster (or any other loosening lube like WD-40)? A torque screwdriver should get them out (either drill or hammering type). A Grabit Pro bit will definitely do the job if you intend on replacing those screws anyway. Some heat on the thread area might loosen them up too.

Offline calj737

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Re: CB550 rocker cover screws
« Reply #2 on: November 28, 2015, 01:54:15 PM »
They are not Phillips screws, they're JIS (Japanese Industrial Standard) and use a very different bit. As those are now badly stripped, drill the head off and then remove the cover (remember to release the valve tension first!) and then turn the remaining shanks out by hand.
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Offline mrbreeze

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Re: CB550 rocker cover screws
« Reply #3 on: November 28, 2015, 02:08:06 PM »
Impact driver or if you can get your hands on an air hammer.....better yet. Put anti seize on the new screws and consider going to allen heads.
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Offline Zaipai

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Re: CB550 rocker cover screws
« Reply #4 on: November 28, 2015, 02:43:52 PM »
They are not Phillips screws, they're JIS (Japanese Industrial Standard) and use a very different bit. As those are now badly stripped, drill the head off and then remove the cover (remember to release the valve tension first!) and then turn the remaining shanks out by hand.
Yes this is the best way and they are JIS #3 bits if you can find one you can try that but calj737 has the best solution so far.

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Offline separatist

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Re: CB550 rocker cover screws
« Reply #5 on: November 28, 2015, 02:55:00 PM »
Thanks all. First time on a Japanese instead of Italians and Germans. JIS? Replacing with torx...

Offline calj737

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Re: CB550 rocker cover screws
« Reply #6 on: November 28, 2015, 03:15:50 PM »
Almost all of the "cover" screws are 6mm/1.0 pitch. You can sift thru the parts fiches and find exact lengths for each and every screw in case you get mixed up. Apply a dab of antisieze pin re-install and you'll be golden!
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Offline Pan1cReaper

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Re: CB550 rocker cover screws
« Reply #7 on: November 28, 2015, 07:41:20 PM »
Impact driver or if you can get your hands on an air hammer.....better yet. Put anti seize on the new screws and consider going to allen heads.

Just curious, but what would you do with an air hammer to those little screws???

Offline mrbreeze

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Re: CB550 rocker cover screws
« Reply #8 on: November 28, 2015, 10:00:25 PM »
Loosen them up. I've had stubborn screws that wouldn't come out with a driver. I'm not saying to go to town on it with the hammer but it's worked for me lots of times.
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Offline calj737

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Re: CB550 rocker cover screws
« Reply #9 on: November 29, 2015, 05:05:04 AM »
Just curious, but what would you do with an air hammer to those little screws???
An Impact Hammer is not an air-driven tool, its an elbow-driven tool. Essentially, its a large screwdriver that accepts a hammer blow, then as you apply down pressure during the blow, you/it "twist" the screw as an unlocking motion. Here's an example:
http://www.tooltopia.com/otc-tools-4607.aspx?utm_source=google&utm_medium=cpc&utm_campaign=paid_search_google_pla&scid=scplp7025328&gclid=CLDlvY7ZtckCFYIlHwodMoUEoQ
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Offline Pan1cReaper

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Re: CB550 rocker cover screws
« Reply #10 on: November 29, 2015, 02:09:55 PM »
I have enough experience beating an impact driver, if that's what you mean instead of impact hammer. The quote says air hammer. Thanks though!

Offline mrbreeze

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Re: CB550 rocker cover screws
« Reply #11 on: November 29, 2015, 06:31:37 PM »
I said AIR hammer! You don't just reef on it. Usually a couple of quick blasts will loosen up a stuck screw. Cal is showing a picture of an impact driver although I'm not familiar with that type.
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Offline Pan1cReaper

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Re: CB550 rocker cover screws
« Reply #12 on: November 30, 2015, 10:09:20 AM »
I've used one on larger stuff, I guess you could carefully tap it a few times. I'd be afraid I'd knock the head of the screw off! I see what you're saying though.