heres another scenario---brother had a 88 7.3..start,good psi, as soon as warm,zero. so,took off the rear cooler header--and the relief valve was----------------STUCK OPEN!!!!!!-------i took it home,polished the valve with FINE scotchbrite, and staked it back together. he had good oil pressure, even on the day he traded it off for a way newer one. we went thru a bunch of other things before discovering this-----all it takes is one little particle to get in that valve,jam it sideways, and goodbye oil pressure--
My oil filter bypass valve has a snap ring. On the vans, does this mean the regulator valve has a snap ring also? (on F-series, when one is snap ringed, BOTH are)
Guess I need to pull this cooler for an inspection.
Anyone know what it takes to get the cooler out without taking out the engine?
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