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MG Midget and Sprite Technical - 3 piece oil control rings

Ok
So I have county brand pistons
These have 3 piece oil control rings.
Question is, do the ends of the corrugated spacer overlap or butt?
They seem a bit baggy butted.
Cheers
Tim
T Dafforn

I over lapped mine....

Remember to NOT aligine the ring gaps...which Is tough when you consider the oil ring is a 3 part and 2 compression rings

Prop
Prop and the Blackhole Midget

NEVER overlap the spacer of that type of ring. They are supposed to butt. The spacer has one end painted red, the other green so that after assembly you can check that the spacer hasn't slipped and overlapped while the top and bottom rails are fitted to it (occasionally can).

There should be instructions in the box with the rings, and they stress that the rings must butt, to the point of doing a final check that the red and green ends are both visible just before the ring compressor is fitted.
Paul Walbran

Prop - you'll have no real scraping action with the expander ring overlapped - as Paulk says, the coloured ends are for a good reason!
Chris at Octarine Services

Ok. Went to the local Austin healey spares place and had a look at the instructions on a pack of new pistons. (My pistons came without instructions, as the engineering shop that did he rebore had lost them). And yes the corrugated ring needs to be butted and not overlapped. This explains the epic oil use my engine had.
So have taken my pistons out to remedy. The two oil rings and the spacer look good, they have only done 30 mins running to bed in he cam. Do you think they are good to reuse?
Cheers
Tim
T Dafforn

Yes - they'll be fine!
Chris at Octarine Services

Well thats interesting

Ive actually got a 4 piece oil ring set, the AE instuctions says to butt them...the deves rings instructions talk about how to assemble but never mention butting the ends... the machine shop said to overlap by a couple of ridges

At least thats what I think I remember

I guess l will pull a pistion tomarrow and see exactly what I did...im certianly 2nd guessing my self now

Prop
Prop and the Blackhole Midget

Like this
https://www.youtube.com/watch?v=Zbgww-YTOqE
F Pollock

Prop, the 4-pce oil ring is an older design which Deves still do. The 3 piece ring is usually considered as being easier on the bore (less wear, also less drag) while still giveing excellent oil control, which is why it is used so widely now.
Paul Walbran

Okay....now im offically freaked out.... im pulling a piston to see what ive got and what I did 5 years ago

God I hate 2nd guessing myself, is there anything worse

Prop
Prop and the Blackhole Midget

Prop
Know what you mean. Just took mine out and reset the rings butted.
Tim
T Dafforn

This thread was discussed between 20/09/2013 and 22/09/2013

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