excessive oil pressure

[bromak]

My newly rebuilt 6.5td has suddenly developed high oil pressure and lifter noise. Does anyone have a diagram of the oil passages and where the blockage may be?

[Robyn]

I dont have a diagram, but the oil flows from the oil pump to the oil cooler line outlet fitting, from there, through the cooler and back to engine block.

Into the block, through the filter and then into the LH lifter gallery, from there, around the groove in the block behind the cam bearings and down to the mains.

The oil pressure switch is on the first leg of the return from the cooler/filters;;

Check to see if you have any oil pressure at the Turbo oil supply.

If no oil is found at the turbo then the issue is the feed to the RH lifter gallery.

Was this a used GM block or a new aftermarket block???


I have seen a few of the aftermarket blocks come with oilly shavings plugging the main oil feed passage to the block feed.

At this juncture, I would say that the engine is going to need to come back out and apart.

If for no other reason than to inspect the innards to see what else if anything is fouled up.

High oil pressure means a blockage somewhere, and the clacking lifters means no oil to them.

The cooler is supposed to be able to bypass if it becomes plugged.

There is a bypass valve in the block for the cooler as well as a filter bypass in the block too.

Good luck and keep us posted.

Missy

[rustyk]

Before you do anything, put a manual gauge and see what the oil pressure really is.

Not having access to the gauge, check the resistance on the sending unit, and replace if necessary.