Oil pressure
#1
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RACING JUNKIE
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Join Date: Dec 2006
Location: Abingdon,Virginia
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Oil pressure
Just got thru rebuilding a 318 mopar magnum engine, At running temp the engine will not hold oil pressure @idle running temp it will fall to 0 psi, tried everything i know,everything in engine is new, tried three oil pumps, two were high volume, Have removed main cap's bearings in correctly, removed cam bearings in correctly, replaced pickup twice, Loosing the rest of my hair on this one :? :?
''JUST MY TWO CENT'S WORTH''
''JUST MY TWO CENT'S WORTH''
#4
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RACING JUNKIE
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Yes have a electric one that hooks up to engine test machine, shows engine temp, scope all cylinder's for power balance, etc, + manual gauge, both drops to 0 psi @200 degrees @ idle, no fram filter, mopar filter. Thought about that filter collapse Changed it but no help, Checked drive shaft good condition,start getting lifter tap shut her down quick, Added thing talked to owner about a hour ago he told me it was doing this same thing before i got to it. he was running it like this.
''JUST MY TWO CENT'S WORTH''
''JUST MY TWO CENT'S WORTH''
#5
MARK , It sounds like an oil passage plug has backed out somewhere , not sure how a mopar is made , but on some ford blocks there is a small freeze plug in lifter valley in an oil galley , had one come out and lose pressure , after I wrestled with oil pan to change pump , I removed intake and found the plug out ( lucked out ) , does mopar have any plugs behind timing gears??? if it was like that before then it has to be an open somehere since you changed everything else ...
#6
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RACING JUNKIE
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pesiol sludged up that fast huh? j/k had a 350 lost oil pressure one day never came back at least what 2 gauges said ran that way for 6 months brfore had a chance to tear down no damage and never figured it out just damn lucky hows the pick up tube? just idea but maybe a small crack and expands when warmed up
#7
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RACING JUNKIE
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No mopar doesn't have those plug's, It has two holes there so oil can run out on timing chain then the oil goes down the front cover to pan.Changed pickup tube twice.
#8
lets assume that it IS pumping since you changed everything , it is not making it to the lifters , so there is an opening between the pump and the lifter passages somewhere,,either that or some reason it just not pumping , can you spin the pump with dist out and see if its pumping , does mopar have the sealing rings around dist shaft where it passes thru oil galley????
#9
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RACING JUNKIE
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Join Date: Dec 2006
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Ok the magnum engine is setup just like chevy engine oil's thru push rod's to rockers, does good untill engine get's running temp then you can watch it just trickle away. Running 10w30 oil. Now this engine is not in the truck it is on a break in stand with all the gauges, tach,raditor, etc.