Tram and I have had real good results using SliKroil to un-seize rings. Put a few ounces in, set for a day, turn the engine over, repeat for a week. For mine, after part way, found Kleen so used a mix. No more puff of oil on start up and the piston slap is mostly gone, plus seems like an odd banging noise is getting better since now mostly gone and much quieter (got Kleen in the oil).

Hope this helps.

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Current fleet:

1985 Mercedes-Benz 280TE - Waiting for heart surgery.

1985 Mercedes-Benz 300TDT - Rear ended 23 September 2016 and now looking for a new home.

1979 Mercedes-Benz 300TD - Parted out.

1964 Volkswgen Beetle - Vater's since September 1968 and undergoing a restoration.

1971 Volkswagen Sunroof Squareback with F.I. - in need of full restoration.

1971 Volkswagen Squareback automatic with F.I. - Vacationing with her caretaker until he is in better health.