Mitsubishi Piston

[CStoica]

Hi all. Hoping for information. This piston came to me through my great uncle. The story behind it is that it came from a Japanese Zero that was shot down in the pacific. I do not know the exact area. Anyways after poking around I do t believe it's from an A6M as I believe the bore is too big. This measures a little over 5 3/4". However There is a a Mitsubishi emblem stamped into it. So I believe it is Japanese. Just not sure what. I can get more precise measurements if need be. Hopefully somebody may know where to start. Thanks.

 

[Shinpachi]

A good collection, CStoica.
That is from a Mitsubishi Kasei or its varient like A18 with the bore 150mm (approx 5 7/8").

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[CStoica]

A good collection, CStoica.
That is from a Mitsubishi Kasei or its varient like A18 with the bore 150mm (approx 5 7/8").

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Thanks. I see those engines were installed in a variety of aircraft. I was told it came from a 'zero'. So I'm thinking it came from a fighter and not a bomber. There was a wallet and handgun also. However they could not be found after my father passed away. Which is very disappointing. But thanks for the information

 

[Shinpachi]

You are welcome, CStoica.
If the "Zero" implys its origin, that piston may be from a naval plane like a G4M as it was popular in the Pacific Theater.

 

[CStoica]

You are welcome, CStoica.
If the "Zero" implys its origin, that piston may be from a naval plane like a G4M as it was popular in the Pacific Theater.

Yes. I see this engine was used in a variety of aircraft. I'm assuming, but not sure, that US troops may have referred to all Japanese planes as 'zeros'. Or at least the fighters. I did measure the piston. It measures 148mm. Which seems a bit small for a 150mm bore. A lot of clearance. But it's a forged piston in an air cooled cylinder. So maybe that's normal. Hard to find specifications.

 

[Shinpachi]

Clearance would be like that.
Diagram from Kasei 11(or Ha-101) manual.