<VV> Oil Pressure Release Valve

[Frank DuVal]

Maybe he has one of those defective oil filters I have read about 
recently. But 149 miles?

BTW, my shop manual says # 11 is the oil cooler bypass valve. Is the oil 
cooler plugged? Not cooling oil could be an issue if the engine was run 
hard for that 149 miles (not likely). Or the stuck valve could be 
indicative of other trash in the system that plugged the hole leading to 
the failed bearing. I would look there first.

Of course don't overlook the failure to torque a rod cap... I  did it 
once.... Heard it knock after driving it across the street. Not even a 
mile. Opened it up, replaced the bearing , made sure I torqued it, and 
it ran happily ever after.

Frank DuVal

On 8/29/2011 7:52 PM, Bryan Blackwell wrote:
> That's the oil cooler bypass valve.  It opens if the oil is too thick to pass through the cooler, or the cooler is plugged.  It could be a clue, but I can't see how it could be a cause.
>
> --Bryan
>
> On Aug 29, 2011, at 1:29 PM, Brian wrote:
>
>> A friend's recently rebuilt 102 HP engine lasted only 149 miles before destroying at least one rod bearing.  In the post mortem tear down, it was discovered that the pressure relief vale in the rear cover was stuck in the open(/) down position.  (See Item 11 of the oil system diagram in  the 1965 shop manual.) What is the purpose of this valve?  What happens if it is stuck in the down position.  Could there be any tie in to the failed rod bearing? P.S. There may be more than one failed bearing--the others not yet removed.