Crank bearing shells need replacing?

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MexicanGringo
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Crank bearing shells need replacing?

Post by MexicanGringo » Fri Nov 21, 2008 6:24 pm

Hey all, just removed my crankshaft and noticed damage on both outer shells, upper & lower.. Not sure how clear it from picture, but the one has quite a deep scratch and the other pitting on the upper sidewall

Image

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viper_biker
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Re: Crank bearing shells need replacing?

Post by viper_biker » Fri Nov 21, 2008 8:03 pm

I don't know much about the engine internals, but if that was my motor I'd be replacing them.
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Jon
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Re: Crank bearing shells need replacing?

Post by Jon » Fri Nov 21, 2008 8:12 pm

If you are stripping an engine I would replace them regardless, any scores on the crank?
The bearings are designed to pit quite easily; it is to allow any crud to embed into the bearing without damaging the crank.

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Sligeach
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Re: Crank bearing shells need replacing?

Post by Sligeach » Fri Nov 21, 2008 8:16 pm

as the other lads are alluding to, as long as you have the engine stripped down to that level, replacing them seems the sensible thing to do. what looks like minimal wear on the internals can be a lot at 13.5K RPM!!

MexicanGringo
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Re: Crank bearing shells need replacing?

Post by MexicanGringo » Fri Nov 21, 2008 9:41 pm

Cheers seems like the sensible thing to do, you got2 replace them all as a set i believe? Crankshaft journals in good condition so bearings must have saved them as jon suggested, just remains to be seen what ridiculous price honda will quote me!

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Re: Crank bearing shells need replacing?

Post by stevie » Fri Nov 21, 2008 9:51 pm

what has caused the scoring? check for any tiny bits of dirt or metal in the motor run around it with a magnet to pick up any litle loose bits u may not be able to see or pick up, i allways put a magnet on the outside of my oil filter, u would be supprised what it picks up, this helps a bit but you cant avoid wear and tear with a high reving engine, why have you taken the engine apart if you wernt going to replace the worn parts,was ther another probolem? if youve got the motor striped to this point it wouldnt make sence not to give it a compleat re fresh. like new main & con rod bearings, replace con rod bolts, piston rings, tidy up the ports with some fine wet and dry, re do the valve seats, steam clean the engine (dishwasher will do), ect..

MexicanGringo
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Re: Crank bearing shells need replacing?

Post by MexicanGringo » Sat Nov 22, 2008 8:14 pm

Yeah plan on servicing all the obvious things, head gasket was leaking coolant into one cylinder, that was the major problem, now just gona get bores honed & new rings,main bearings and maybe con rod bearings,tho they look fine.. Done the valve lapping & general clean up of engine

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Psychosomatic88
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Re: Crank bearing shells need replacing?

Post by Psychosomatic88 » Sat Nov 22, 2008 8:24 pm

440 big bore. you know you want to.
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Re: Crank bearing shells need replacing?

Post by wullvfr » Sat Nov 22, 2008 8:41 pm

Psychosomatic88 wrote:440 big bore. you know you want to.
:lol: :lol: :lol:

thats the road to go down!!!!!!!!!


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Jon
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Re: Crank bearing shells need replacing?

Post by Jon » Sun Nov 23, 2008 12:27 am

Anyone have hands on experience witht he 440 kits?
Dyno runs, owned one ect?

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