Cylinder Porisity

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Dave B
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Cylinder Porisity

Post by Dave B »

I have read on here about cylinders developing little pock marks due to porisity. Received my cylinder back from being replated and there are a lot of these marks on the mating surface to the head. The plater never said anything about this being an issue, just a little concerned that the gasket may not seal correctly. Has anyone else experienced this?
http://imgur.com/a/FSv8o
pumpguy
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Cylinder Porisity

Post by pumpguy »

That's about how mine looked when it came back from the plater.

As I understand it, it is a result of the etching process they do for surface prep prior to plating.

Little imperfections in the joint surface are actually desirable. They give the gasket an irregular surface to bed into, resulting in a better seal.

You can always use a light smear of Kawasaki Bond silicone sealant or similar.
Dave B
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Re: Cylinder Porisity

Post by Dave B »

Never really considered it to be desirable....I never use silicone on a gasket.
The head gasket from the Moose gasket kit I have doesn't have the sticky rubbery surface like the stock gasket. I may pick up a stock one just for the added piece of mind.
ico135
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Cylinder Porisity

Post by ico135 »

I recently received my cylinder back from Millennium and noticed small little imperfections. I spoke with them about it and they informed me that it would not be an issue and told me it was Porosity. He stated that KDX's were really bad about it due to either poor craftsmanship or materials, i don't recall. But anyway they have an article available on there website that goes into quite a bit of detail. I would link it but there website seems to be down at the moment.
Dave B
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Re: Cylinder Porisity

Post by Dave B »

I talked to the platers today and they basically said the same thing. If their quality control thought that it would have been an issue they would have addressed it.
Thanks for the comments!
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SS109
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Cylinder Porisity

Post by SS109 »

Porosity in the cylinder bore is a common occurrence when getting a cylinder replated. It won't hurt anything in the cylinder. However, I have personally never seen or heard of porosity issues on the head gasket mating surface but that's just my experience and is more than likely a non-issue.
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