This old 550 crankcase...

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pjac
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This old 550 crankcase...

Post by pjac »

Don't know much here, this is my first post on Sundial!! Hoping someone can help...

If I start with this... could I clean the surface rust off the crank and make sure the bearings are good and leave it together? Take a chance and not split the case? Is there a way to tell if the inner crank seal is good? Etc... Or am I talking crazy?

Don't mind splitting and refurbing if necessary. Will the case areas around the crank need attention?

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Clifford
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Re: This old 550 crankcase...

Post by Clifford »

Split the cases and start from the beginning!
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rngdng
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Re: This old 550 crankcase...

Post by rngdng »

I doubt that the crank is good with that much water and crud in there.


Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
pjac
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Re: This old 550 crankcase...

Post by pjac »

I suppose if the journals have any marring on them at all then it might run a resurface job up past a reasonable cost point. Back to the drawing board...
rngdng
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Re: This old 550 crankcase...

Post by rngdng »

pjac wrote:I suppose if the journals have any marring on them at all then it might run a resurface job up past a reasonable cost point. Back to the drawing board...
In a crank rebuild you can replace any bad bearings, and the seals. Where the crank contacts the cases (the journals) is not a big issue like it would be with a car or many four-stroke bikes.



Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
pjac
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Re: This old 550 crankcase...

Post by pjac »

So, that old nasty crank and cases are not too far gone to be used again if the crank was rebuilt with new bearings and seals and trued up?
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Alan H
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Re: This old 550 crankcase...

Post by Alan H »

pjac wrote:So, that old nasty crank and cases are not too far gone to be used again if the crank was rebuilt with new bearings and seals and trued up?
No. Cases media blast and cranks can be refurbed. Clean it as much as possible before the crank builder gets it.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
rngdng
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Re: This old 550 crankcase...

Post by rngdng »

pjac wrote:So, that old nasty crank and cases are not too far gone to be used again if the crank was rebuilt with new bearings and seals and trued up?
Good news!! They can be fixed.



Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
pjac
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Re: This old 550 crankcase...

Post by pjac »

Thanks Gents! That is good news
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Re: This old 550 crankcase...

Post by Vintageman »

If you have rust on the connecting rod surfaces (Big End - Little End), The rods are no good, roller bearing and crank pin as well could be rust compromised. Sure it would run for while but it won't be long before it gets noisy and goes bad or throws roller needle about as you rev it up

Rust is the worst thing for cranks even a little if on precision surfaces is a problem sooner than later. The bike can look nice on the outside, but for example if the crank wan't turned for many moons, those mating surfaces grab moisture a little at time causing tooth decay... I mean rusting decay weakening the enamel ... i mean metal surface. The one downside of two stroke is they required roller bearing for lubrication. Those have large air gaps where air brings along moisture and the few contract surface rust first even if no liquid pored in. Your case looks like liquid did get in to crankcase, not just humid air.
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Suzukidave
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Re: This old 550 crankcase...

Post by Suzukidave »

You may be better off finding a good crank on Ebay , with new rods , bearings and seals your going to be in for over $500 i bet :shock:
the older i get the faster i was
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