That is a great summary...modern engines are so good that I've not done a set of rings in, oh, 30 years now...but the diagrams and explanations in this summary are excellent, even if I never do another set of rings...
interesting article. They don't seem to recommend honing the cylinders or a re-ring job. I didn't know that chrome rings were still made, outside of weedeaters and chainsaws. I've seen chrome rings never seat in a rebuild. I am interested in the gapless ring designs. but since i don't hear of them being used in factory engines i wonder if its a cost or reliability issue.
Extra credit to who can identify the engine/bay of the vehicle on page 70. It looks visually like a transverse-mounted V-8 engine, but I know of very few of those (outside of previous Cadillac and Lincoln efforts). This doesn't look like a Cadillac or a Lincoln.
Originally Posted By: SteveSRT8
Can anyone here tell me where the ideas came from that a thicker viscosity oil can actually change the end gap on a piston ring?
Someone in this forum actually dropped that bomb on me and I have searched far and wide for anything to corroborate it...
I've never heard that either. The old rule was .003-004 per inch of bore.
Originally Posted By: spasm3
Originally Posted By: SteveSRT8
Can anyone here tell me where the ideas came from that a thicker viscosity oil can actually change the end gap on a piston ring?
Someone in this forum actually dropped that bomb on me and I have searched far and wide for anything to corroborate it...
I've never heard that either. The old rule was .003-004 per inch of bore.
I ran this by a 72 year old Machinist in the Family here and he said balderdash. I also put the question up on some other forums as well. No one anywhere can say it's true.
Originally Posted By: SteveSRT8
Can anyone here tell me where the ideas came from that a thicker viscosity oil can actually change the end gap on a piston ring?
Someone in this forum actually dropped that bomb on me and I have searched far and wide for anything to corroborate it...
in full fluid lubrication, there's a layer of fluid between the bore and the ring, reducing the bore size and squeezing the ring gap more closed.
That's all I can think of... the gap will reduce by 6.28312 times the oil film thickness.