Nissan 240SX Forums banner

sr20det piston rings.

4.9K views 6 replies 4 participants last post by  Dolby109  
#1 ·
I'm rebuilding my motor and I know there's a certain way to put the piston rings in but I don't know exactly what it is... I mean, the gaps in the rings are supposed to be a certain # of degrees apart arent they? I don't know if it's like 90, 180, ...? Does anyone know what I'm talking about?
 
#2 ·
top ring should have the piston ring aligned with the cylinder bank line, so there's no lateral force where the gap is. Ring below it should be 120 degrees off of that and the 3rd should be 120 degrees from that.

Hope this helps for my 1st sentance:
OOOO are cylinders so your top ring gaps would be aligned like this - - - -
 
#5 ·
rexbo said:
top ring should have the piston ring aligned with the cylinder bank line, so there's no lateral force where the gap is. Ring below it should be 120 degrees off of that and the 3rd should be 120 degrees from that.
Third ring??? WTF you talkin bout?

The third ring is the oil seal ring and has 3 parts which require their own seperation.

For the compression rings I dont remember the spacing, but the FSM says, and you def need that to build the motor.
Also put one or more of the comp rings in the cyl bore to make sure its gapped right first. There should be a small gap...but not too much.
Mine was actually too large out of spec but the motor still runs fine and doesnt blow any oil.

The oil seal rings also should be spaced a certain way...again check the FSM.
 
#6 ·
well if there are only two rings put them 180 degrees apart. Last engine i assembled was a motorcycle engine and it had three rings, so you put them 120 degrees apart.