This is one for a tech. dose the LBZ have a dedicated cylinder wall lubrication system ( con-rod squirt holes, oil jets to supply the oil rings) or dose the motor rely on the cooling jets for this process?
I assumed they were always "on" but if your point is true might it be Emissions related? Just thinking out loud):hGeabis is asking the question to determine if cylinder wall lubrication has a dedicated oil provision, apart from the cooling squirters. It is rumored that under 29 psi, piston squirters stop. As to why this has been designed this way I can't say. I have ideas, they are just speculation.
yes most diesel engines have them to cool the aluminum piston. PSD had a problem with them a few years back 7.3L i believe with the jets falling off and the cylinder wall wearing. its been rumored that the dmax disables cooling jets below 29psi. and I'm trying to determine if this is true or not. as to the purpose of the jets disabling i do not know why they would disable them but as far as i can see there is no mechanical valve or regulator that dose so i think it may be a factor of achieving enough pressure on hot thin oil to be able to squirt to the piston bottom (may bee a design flaw, may designed to achieve some purpose or may not even be true)where does it squirt the oil? on the lower skirt, or up inside the piston? where are these jets located?
do the cummins/powerstroke's have 'em?