Water pump bearings in #2 cyl on 5.9 cummins

docone · Oct 2, 2014

I recently tore down a 5.9 Cummins, and discovered water pump bearings in the # 2 cyl. Can anyone out there shed a little light on this.
A little history; Water pump failed, turbo overheated and caught fire. Drained all fluids, replaced W/P, Turbo, Tstat, belt and pulleys, refilled all all fluids, started engine, would not come up to speed, so took head off and found the old W/P bearings hammering the crap out of # 2. No idea how they got there.

puckgrinder85 · Oct 2, 2014

You sure it didn't come from the turbo?

RickB · Oct 2, 2014

puckgrinder85 said:
You sure it didn't come from the turbo?

I'd be pretty certain they did. I can't visualize any way for water pump bearings to get in a cylinder without somebody tossing them in the intake.

docone · Oct 3, 2014

I dismantled both the turbo and the W/P and the turbo is intact, there is scarring on the exhaust impeller from the w/p brg shrapnel going through. my best guess is the coolant journals in the exh manifold are breached and the brg pieces were drawn into #2 through the exh valve. the head shows markings on the valve heads and seats.
This unit is a Fire Booster Pump engine, and has a raw water heat exchanger cooling system attached.

RickB · Oct 3, 2014

docone said:
I dismantled both the turbo and the W/P and the turbo is intact, there is scarring on the exhaust impeller from the w/p brg shrapnel going through. my best guess is the coolant journals in the exh manifold are breached and the brg pieces were drawn into #2 through the exh valve. the head shows markings on the valve heads and seats.
This unit is a Fire Booster Pump engine, and has a raw water heat exchanger cooling system attached.

So the bearing pieces moved against the flow direction of the exhaust gasses and entered the combustion chamber from the water jacket by way of the exhaust manifold? How much water entered as well? If this actually happened, at the very minimum, the cylinder in question would be washed clean of carbon. Is it? Which turbo is intact, the first or second?