Thread: Are we sure regular SR20DE engines don't have piston oil squirters?

I vote we revoke his Moderator status.

Mushrooms?

I can see there is reasonable skepticism as to where the jet aims the oil during rotation. I'll try some experiments and come back with findings.

I think the important thing to note is that aftermarket connecting rods do not incorporate these oil squirters.

Fixed.

However, this is likely a constant stream and as such when the rod angle changes during the rotation, the direction of the oil will change. This will likely spray the under side of piston.

Exactly why piston shapes are different on the major and minor thrust sides.

Do we know for sure this squirter is on the thrust side?

I'll be doing some tests to see exactly where this squirter aims during the full rotation.

Actually it does. Take a look at this pic.



This shows the oil hole on the thrust side since the engine rotates clockwise. Take a look at the piston markings identifying "front".

I for one would like to see the test results. I have a feeling though that the cylinder wall is sprayed on the downward stroke and the piston on the upward. Actually, thinking about that more makes a lot f sense considering on the downward power stroke you would want fresh oil on the cylinder wall where the most force is exerted. Secondly on the upward compression oil would be sprayed on the bottom side of the piston cooling it before the next power stroke.

Thanks ebinkerd, I should have seen that.
Interestingly enough, it's also squirting on the intake side wich is more prone to detonation damage.


If the job of this squirter is to lubricate the cylinder wall, how does the wrist pin get lubricated?



Can we agree that any device that squirts the piston with oil is a piston oil squirter?