Carburettor piston wear

by Remi Guerner in 912 / 914 Technical Questions 6 years ago

Hello,

When I removed the carb pistons to replace the jet needle circlips per SB-912-073, I found one of them was showing sign of wear one one place. Photos attached. Is it wear or was it done during manufacturing? Has anyone encountered this case?

The engine is one year old 912ULS, has done 86 hours since new and runs perfectly well. Any advice welcome.

Regards

Remi

7716_1_IMG_0069.jpg (You do not have access to download this file.)

7716_1_IMG_0070.jpg (You do not have access to download this file.)

Re: Carburettor piston wear

by Garrett Wysocki » 6 years ago

Garrett Wysocki

1 572 1.45k

Your right that does not look normal, I would take the issue up with Rotax.

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Re: Carburettor piston wear

by Peter Kl. » 6 years ago

Peter Kl.

7 230 382

Don‘t fix it if it ain’t broken.

Slighty polish the blind spots, fly for another 50 hours and re-check...

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Re: Carburettor piston wear

by Remi Guerner » 5 years ago

Remi Guerner

2 8 3

Garrett Wysocki wrote:
Your right that does not look normal, I would take the issue up with Rotax.

Garrett,

The Rotax French rep says it is a result of abnormal vibration that should be fixed. I disagree about that as I believe excessive vibrations would likely cause the piston to wear on both sides and on both carbs. The wear is on one location on carb 1/3 only. My carbs are perfectly balanced and the prop has been dynamically balanced and the measured vibration level was very low. I will file a CSIR.

Remi

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