New rings

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Propshaft
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New rings

Post by Propshaft »

I am about to replace the piston rings in a 1275 midget engine , any does and do nots your advice welcome
philthehill
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Re: New rings

Post by philthehill »

Make sure that you glaze bust the cylinder walls before fitting the new rings.
Make sure that everything is spotless after glaze busting.
Make sure that you get the rings the right way up - usually marked with a 'T' for top.
Make sure that you check the ring gap.
Make sure that the ring gaps are at least 90 degrees apart from the ring above and below.
Make sure that the rings, bores and pistons are swamped in oil.
Phil

Propshaft
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Re: New rings

Post by Propshaft »

Thanks for the info . How many thou would you advise for the ring gap
philthehill
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Re: New rings

Post by philthehill »

The fitted gap for the 1275cc Midget/Sprite piston rings - that is with the piston ring pressed down into the non worn part of the bore by an inverted piston to keep the ring square to the bore:-
Top ring...............0.011" - 0.016"
Second and third.....0.008" - 0.013"
Oil control ring.......0.012" - 0.028"

The ring to groove clearance - that is the clearance between the top of the ring and the ring grove wall .......top, second and third.......0015" - 0.0035".
Phil

Propshaft
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Re: New rings

Post by Propshaft »

Again Thanks
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