T 100 oil feed return problem

[iansoady]

I've never heard of or experienced wear caused by ring ends.......

[Rex]

Maybe not, but the little marks are sometimes visible to the naked eye. A sharp edge will always wear more than a continuous curved ring surface.
It's like so many things in engineering, it's reducing the risk of potential problems by following a simple rule.
In the past, people used to say that to have the gaps in a line would "let the compression escape" which really was tripe.

[chaterlea25]

Hi All,
Recent thinking is that the rings rotate on the pistons as the engine runs, so does it matter where you place them?
I was shown / told to place the ring gaps on the on thrust areas, ie to the sides towards the gudgeon pin
many many years ago

John

[Rex]

Assuming that all three rotate at a similar speed, then no, other than the initial spacing.

[chaterlea25]

Hi Rex,
I often wondered how they found out that the rings rotated unless they did multiple assemblies and dismantling?

When I served my time another thing I was told when removing electric motors for repair that had multiple belts on the drive was to mark each belt so they would be replaced in the positions and locations that they were removed and have the same alignment
A while ago I did this when I rebuilt the motor on my lathe (4 belts)
After the first run the alignment marks had all moved by a considerable amount and the marks continued to drift all over the place   

John

[Rex]

Looking after some huge four belt driven vent fans many years ago you could see that only some of the four belts were driving and others were running a little slack.
I put it down to manufacturing tolerances in the belt lengths.

[chaterlea25]

Hi Rex
When belts are mismatched they can set up horrible chatter and vibration
Matched sets of belts are expensive,
I would think that my lathe belts were the originals but have no way of knowing

John

[iansoady]

Hi Rex,
I often wondered how they found out that the rings rotated unless they did multiple assemblies and dismantling?

https://www.highpowermedia.com/blog/3954/rotation-of-piston-rings

[chaterlea25]

Hi Ian
Thanks for the link Ian

John