engine cylinder head


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robsgreen
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engine cylinder head

Post by robsgreen »

Hi Guys
Happy new year to you all.

I've just completed the top end rebuild on my CBX1000 but came to fit the top oil pipe bolt (flexi pipe from crankcase to cylinder head) and the bolt is pretty gnarled up but does torque up OK. I expect the internal threads in the cylinder head are not too good either. The bolt feels tight when its screwed up to the oil union. I had forgotten about this as the bike has been down for so long. I'm thinking of taking the head off again and getting the thread heli-coiled and fitting a good replacement bolt. I could do this in situ, but I'm worried about keeping everything square. My question is: if I take the cylinder head off, do I also have to take the barrels off and replace the base gasket and cylinder base o rings, or can I leave them alone? I may also try and run a finishing tap down the internal thread and see if this improves the fit with a new bolt.

Regards
Martin

EMS
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Re: engine cylinder head

Post by EMS »

Those who take engines apart and put them together 3 or 4 times a week may disagree with me, but I have R&R-ed heads without replacing the lower gasket and O-rings. Have not had an issue. 8)

daves79x
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Re: engine cylinder head

Post by daves79x »

Those bolts for the oil hose are special ones that you can't replace with just any bolt - top one is your problem I assume? You could make a bolt I suppose. If the bolt tightens up on the crush washers, I'd run it. I never replace the base gasket if just removing the head.

Dave

robsgreen
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Re: engine cylinder head

Post by robsgreen »

Hi Guys
Thanks for your help.
I've ordered a good used bolt from the six center and brought a finishing tap to run through the existing internal thread. On closer inspection of the bolt, its not as bad as I thought, so I'm just going to replace the bolt with a new one and hopefully that will sort it. Best Regards
Martin

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