Impossible to find KEC 340/5 Piston + Rings

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Connor O
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Joined: Fri Nov 28, 2025 12:14 pm
Real Name: Connor

Impossible to find KEC 340/5 Piston + Rings

Post by Connor O »

Kec 340/5 pistons and or rings seem to be virtually impossible to find. Does anyone have any leads on where to find them? Or does anyone have any they'd be willing to parts with.
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400brian
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Real Name: James T. Kirk
Location: South Central Wisconsin

Re: Impossible to find KEC 340/5 Piston + Rings

Post by 400brian »

340 pistons are the easiest to find of all the piston port engines. 440/5s are the real unobtainium.

I did a quick google search and I see MFG Supply listing std and over sizes. I would argue that their discription is incorrect. All the 340 Kioritz piston port pistons are interchangeable. There is no left or right, and it doesn't matter if the are from the 72 KEC 340 thru the /5. There were part number revisions in the Deere parts catalog, but they subbed back to the earlier engines. If anyone wants to argue that, please show me my error.

MFG Supply's description lists /2 thru /4. Those numbers do not exist, at least not on Deere sleds. The 72 and 73 had KEC340, in 74 the engine tag says 340/5. The /5 engines switched from short to long reach plugs, and more fin area on the jugs and heads. The earliest 340s had 4 bearings on the crank rather than 5, and a 25mm rather than 30mm pto shaft. But the pistons interchange.

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