Spun Bearing - 2.25 liter Diesel

[Tom Santoli]

I bought a Series III last month with a 2.25 liter diesel that the former owner indicated had a bent rod; the price was right and it was otherwise desireable. I had figured replacing the engine into my budget but thought I'd drop the pan on the the existing engine.

#4 rod bearing was spun, se attached photos of crankshaft rod journal and connecting rod cap and bearing.

The other rod bearings seem fine and the bearings are original size.

I'm considering replacing rod bearings (provided crush guage clearances work) as well as replacing the oil pump and seeing if it will run build oil pressure.

The crank rod journal is marred but I don't feel gooves or allot of relief.

How forgiving are these old diesels?

Thanks;

Tom97929793

[o2batsea]

The trouble is that the scoring on the crank will reduce the hydrodynamic cushion that forms between the rotating parts. Your chance of trashing another bearing is high.
In addition, all the tiny metal flakes that shredded off the bearing shell are now well dispersed throughout the entire engine, so there is galling and scoring happening in between every bearing surface even tho the engine would seem to be "OK". In other words, you can't get away with not rebuilding.

[Tom Santoli]

Contrary to the advice on this forum and from others, I went ahead and replaced the rod journal bearings on this engine following some crocus cloth polishing that nicely cleaned up the #4 journal. I also inspected the oil pump and cleaned what ever was accessible to me with the pan off.

I hope to get it running and nurse it along while I search for a replacement engine.

I have it all back together and I've installed a temporary gauge in place of the oil pressure sending unit. When I crank the engine with the hand crank (glow plugs out) I get a quiver from the oil pressure needle but when I crank it with the starter I get 10-12psi.

10-12psi at cranking speed seems pretty good to me, is this adequate oil pressure given this engine speed?

Thanks;

Tom

[SafeAirOne]

10-12psi at cranking speed seems pretty good to me, is this adequate oil pressure given this engine speed?

That's no way of telling. Seeing any oil pressure while cranking is a promising sign but not much else.

Just start it up and see what you've got with the engine warm.

~7psi or less activates the low oil pressure warning light on stock systems.

[o2batsea]

Given that the engine is a goner, anything further you get from it is purely a gift.