hi guys.
please, i need some of your expertise concerning piston rings alignment.
in every overhaul manual, is indicated via figures, the positioning of the rings, see: A, B and C, no problem with that, but actually i'm itching to align them 180 degrees opposite, for example, if upper is fwd, second will be facing back, and so, sure keeping the same order for everyone, but before i do it, i'd like to ask your oppinion on the matter, i know the recomended positioning is to prevent exessive blow-by, but to me it looks even better 180 degrees appart, wouldnt you say so?
thank you gentlemen. :hail:
Fernando.

 

They actually rotate around the piston as it goes up and down. That's why you want the cross-hatch pattern on the cyl walls.

But if any one of the ring ends lines up with any other, they will tend to develop deeper wear at some point around the cyl because of that, and eventually they'll hang up in the wear and stop rotating, and when they don't rotate, they score the cyl vertically which is what causes excessive blow-by and oil consumption.

So for max possible engine life, don't line any of them up with any others.

 

Not that it makes huge difference where you start them (since they move) but I've always followed 2 simple rules:

1. Don't line up any of the gaps.

2. Don't put any of the gaps on the thrust side of the piston.

 

some of my manuals show where to position each ring, not sure it really matter as long as the gaps don't line up like rb said. if i have a manual that shows where to position the rings i do "just in case".

 

so as long as they are appart, it doesnt matter if they are 180 degrees opposite? i'm thinking about for example, the upper one towards the front of the engine and the second towards the back, i think it will be harder for them to align.
another question, the trust side is it parallel to the crank shaft or transversal to it?
thanks again guys.
Fernando.

 

front of engine would be 9 o clock, lifter valley 12 o clock
oil ring spacer gap between 11 and 1
oil ring rail 7
2nd ring at 6
top ring at 12

 

thanks ede, you're the man. :hail:
Fernando.