lost all oil pressure but not flow

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UDUST81

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hey everyone, just want to start out that i appreciate all the help on this site everyone is always super helpful and i greatly appreciate all the help i receive here on FABO anyways on to my question

car is 72 duster, 440 source stroker, 505 c.i. melling high volume oil pump purchased from 440 source, 7 inch deep pan, windage tray stud girdle, joe gibbs high zinc 5w30 oil etc... anyways motor has been running since last fall when cold motor consistently had 70-75 lbs of oil pressure at idle,even in below freezing temps, once water got up to 180f oil generally went down to 15-20lbs but with any throttle application would spike back to over 60-65 lbs. all was good...

well engine has probably about 5 hours of run time on it at this point, this spring i pulled it to fix leaks around the pan rail, timing chain cover and water leaks out of the freeze plugs. reinstalled around a month ago, no leaks

probably put another 3 hours of runtime on it since cruising around the neighborhood fixing other issues that have came up all while no oil pressure issues, well this weekend buddy came over and i needed to get gas so we decided to take it on the approx 3 mile trip to the gas station, we make several 6k rpm pulls on the way no issues, leave the gas station, still rock steady pressure, we head back, make another pull to just before 6k and cruise into the neighborhood off the two lane highway, about 2 blocks from home check oil pressure, its at ZERO, lightly rev it, to see if i have anything and nothing, shut it off and buddy flat tows me back water temp never got above 190 according to aftermarket temp gauge

we check oil level, all good, pull oil line off block start it buddy says its spraying out like crazy okay cool, either have a bad line or gauge, that was saturday skip forward to today and i buy a new line after work install, start it up no pressure, shut it off, pull new line from gauge and put line in water bottle, start it and no oil goes into bottle, disconnect line from block reach in turn key look at block and oil is coming out but my buddy may have been exaggerating a tad, oil is lightly pouring out of block, not quite gushing and spraying like he said....

anyways a lot said there but i wanted to describe problem as accurately as possible to everyone, at this point really dont want to start it anymore than i have to as i feel like i am already pushing my luck seeing it may actually be a pressure problem and not a gauge problem as we anticipated... so any suggestions? im thinking maybe a clogged filter? it is on its third one since initial build but only 1st one since resealing bottom end and freeze plugs, or possibly a broken spring in the oil pump? want to reiterate i have zero oil pressure at any rpm and not one drop came out of new line even with a light rev, other than that motor does not show any signs of anything wrong, just want some tips on where to go from here, as worst case scenario i can think of is possible cam bearing spun or something of that nature anyways any tips would be appreciated just dont want to chance locking motor up changing things will not make difference and testing

thanks FABO!!!
 
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I had a push rod bend once in my 383 Super Bee years ago, no oil pressure but no knocking . Took off the valve covers. Waa laa... lifter popped out and there was a bent push rod. Put the lifter in, changed the pushrod , no issues. . May check that . It had a high volume oil pump too. Good luck!!
Mike
 
if it were mine , at this point I would replace the oil pump and hope nothing is damaged. I know oil is expensive , but I would at least check it for metal before starting it again. I wouldn't even attempt to start it again until I had a new pump in there
 
You could also remove the distributor and intermediate pump drive shaft, install pump priming tool and see what you get for a result.
 
You could also remove the distributor and intermediate pump drive shaft, install pump priming tool and see what you get for a result.
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do the above suggestion first, if its pumping, get another gauge and mount it in the engine compartment so you can watch it. We also had a new oil pump go bad on start up one time on a hemi, it happens . I`d run heavier oil too, these are dinosaurs, not sewing machines.
 
I had a push rod bend once in my 383 Super Bee years ago, no oil pressure but no knocking . Took off the valve covers. Waa laa... lifter popped out and there was a bent push rod. Put the lifter in, changed the pushrod , no issues. . May check that . It had a high volume oil pump too. Good luck!!
Mike
DING DING DING we have a winner! pulled the valve covers and yep theres a hell of an s curve on the intake pushrod of #4 ill pull the rockers and check my other pushrods to see if they are bent as well if not i may just call it bad luck as the cup of the pushrod is loose from the pushrod itself and it looks like theres a ridge inside which probably took up what clearence there was and something had to give...

anyone else have any suggestions while i have the intake off and am checking pushrods?
 
DING DING DING we have a winner! pulled the valve covers and yep theres a hell of an s curve on the intake pushrod of #4 ill pull the rockers and check my other pushrods to see if they are bent as well if not i may just call it bad luck as the cup of the pushrod is loose from the pushrod itself and it looks like theres a ridge inside which probably took up what clearence there was and something had to give...

anyone else have any suggestions while i have the intake off and am checking pushrods?
Cool!! I had stock pushrods in mine and only a Hemi grind cam so it wasn't a lot of lift . I only bent one in 8 years that I owned it. Pull them all and check for straightness on a piece of glass first.
 
I didn't clip a piston, started up the car cold and revved it. ( I was 17) I never did figure out what caused it. But I was low bucking everything then..used pushrods, rockers etc... glad you found the issue.
Mike
 
I bent a rod a semester in my buddies Cleveland. Never figured the pushrods were too long! Erson Hi-flow 2 cam with Cleveland 1.73 rockers. I always get a lifter baffle for the LA's valley, they are cheap and work.
 
change the 5w30 to 20w50 and see where you're at.

My last 440 I used full grooved mains and had barely 10psi per 1,000RPm. Ended up running 20/50 in it and it was fine.

My current 440 uses 0w40 and still has oil pressure on the high side but I'm not complaining.

Both engines have been together for almost 20 years so..
 
DING DING DING we have a winner! pulled the valve covers and yep theres a hell of an s curve on the intake pushrod of #4 ill pull the rockers and check my other pushrods to see if they are bent as well if not i may just call it bad luck as the cup of the pushrod is loose from the pushrod itself and it looks like theres a ridge inside which probably took up what clearence there was and something had to give...

anyone else have any suggestions while i have the intake off and am checking pushrods?
what kind of rockers are you running? If stock, stamped-rockers, I'd check rocker geometry and lifter preload. If adjustable rockers, I'd check shaft oiling/clocking, first. Then, I'd check rocker geometry and lifter preload, second.
 
what kind of rockers are you running? If stock, stamped-rockers, I'd check rocker geometry and lifter preload. If adjustable rockers, I'd check shaft oiling/clocking, first. Then, I'd check rocker geometry and lifter preload, second.
engine has crane ductile iron 1.5 ratio rockers and a solid flat tappet hughes cam
 
engine has crane ductile iron 1.5 ratio rockers and a solid flat tappet hughes cam
OK, then forget preload suggestion. Were all the rocker adjuster locknuts tight? If so, look for correct clocking on shafts for proper oiling, and make sure oil plugs are in both ends of the shafts. Maybe one plug fell out. If any of those things has happened, pull shaft(s) and check shaft(s) and rocker bore, carefully, for signs of galling. There has to be a reason for bent pushrod. If not a geometry issue, then perhaps a clearance issue: coil bind, retainer to guide/seal, valve to piston, etc.
 
Think I`d look a
OK, then forget preload suggestion. Were all the rocker adjuster locknuts tight? If so, look for correct clocking on shafts for proper oiling, and make sure oil plugs are in both ends of the shafts. Maybe one plug fell out. If any of those things has happened, pull shaft(s) and check shaft(s) and rocker bore, carefully, for signs of galling. There has to be a reason for bent pushrod. If not a geometry issue, then perhaps a clearance issue: coil bind, retainer to guide/seal, valve to piston, etc.
k I`d look at the cam and lifters real close too .
 
OK, then forget preload suggestion. Were all the rocker adjuster locknuts tight? If so, look for correct clocking on shafts for proper oiling, and make sure oil plugs are in both ends of the shafts. Maybe one plug fell out. If any of those things has happened, pull shaft(s) and check shaft(s) and rocker bore, carefully, for signs of galling. There has to be a reason for bent pushrod. If not a geometry issue, then perhaps a clearance issue: coil bind, retainer to guide/seal, valve to piston, etc.
all lock nuts are tight, by correct clocking do you mean the pushrods rotating? if so then they are as the paint has slightly worn all around the pushrod where it contacts the head... which btw doesnt look to severe as its just rubbed off paint but has not nicked pushrod i did have to clearance the heads for the 3/8" pushrods when i built motor, perhaps i should go a little more on clearance? could that of caused the bent pushrod?
 
all lock nuts are tight, by correct clocking do you mean the pushrods rotating? if so then they are as the paint has slightly worn all around the pushrod where it contacts the head... which btw doesnt look to severe as its just rubbed off paint but has not nicked pushrod i did have to clearance the heads for the 3/8" pushrods when i built motor, perhaps i should go a little more on clearance? could that of caused the bent pushrod?
yes, clearance on pushrods may be a factor in bending the pushrod, but maybe not THE factor. I haven't worked on a BB for almost 25 yrs, so I don't remember if rocker shaft ends are marked to easily denote lube holes properly like a SB. But if you look at a FSM, the rocker oiling holes on each shaft are at 15 degree angle to the centerline of the shaft attaching bolts. Those oiling hole location is CRITICAL to properly lubricating those adjustable rocker arms. The oiling holes are supposed to favor the valve side of the shaft. If you find that they were incorrectly positioned, you MUST closely examine the bores of the rockers and bottoms of rocker shafts for galling.
 
yes, clearance on pushrods may be a factor in bending the pushrod, but maybe not THE factor. I haven't worked on a BB for almost 25 yrs, so I don't remember if rocker shaft ends are marked to easily denote lube holes properly like a SB. But if you look at a FSM, the rocker oiling holes on each shaft are at 15 degree angle to the centerline of the shaft attaching bolts. Those oiling hole location is CRITICAL to properly lubricating those adjustable rocker arms. The oiling holes are supposed to favor the valve side of the shaft. If you find that they were incorrectly positioned, you MUST closely examine the bores of the rockers and bottoms of rocker shafts for galling.
i can confirm that the oiling holes are in the correct position as when i was building the motor i specifically had to look up which way they went, nevertheless i will double check when disassembling tonight as i have to remove the rockers anyhow


BTW just want to say thanks to everyone on FABO i would be lost without this site the knowledge from all the members and the ability to communicate with so many knowledgeable wrenchers accross the world is priceless, all i've ever done before this build is just basic parts changing and its safe to say this is my first true performance build so i apologize if i seem a little misinformed about things im just a rookie out here trying to build a monster and again couldnt do it without you guys as i have no real world link to anyone here local that has ever built anything to this level thanks again!
 
i can confirm that the oiling holes are in the correct position as when i was building the motor i specifically had to look up which way they went, nevertheless i will double check when disassembling tonight as i have to remove the rockers anyhow


BTW just want to say thanks to everyone on FABO i would be lost without this site the knowledge from all the members and the ability to communicate with so many knowledgeable wrenchers accross the world is priceless, all i've ever done before this build is just basic parts changing and its safe to say this is my first true performance build so i apologize if i seem a little misinformed about things im just a rookie out here trying to build a monster and again couldnt do it without you guys as i have no real world link to anyone here local that has ever built anything to this level thanks again!
on behalf of others on FABO, (many, many more knowledgeable than me, LOL) you're welcome.
If there is absolutely no evidence of galling on shafts or rockers, then my next best guess is like I suggested before, clearance, or rocker to valve geometry issues.
I don't know enough about high-zoot BB''s to comment with much authority, but are the 3/8" pushrods necessary? Perhaps if there are clearance issues, maybe there are diminishing returns on grinding more clearance, if it impinges on intake or coolant passages.
 
I would be less concerned about the top than the lower end. The pass side galley feeds the mains, so if you loose one there, the parts starved most are the rod bearings.

edit - my suggestion is to reassemble it and see what the oil pressures are. If there is ANY change, regardless of how much, I would pull it and check the bearings.
 
well heres my list so far

1.no other pushrods are bent (checked against known straight edge)

2. dont believe any valve to piston interference (pulled plug in cylinder and saw no metal shavings on or inside plug)

3.checked lifter and cam, (no irregular wear, lifter was just sitting in valley right to the rear of its home no damage that i could detect)

4.rockers oiling holes are in correct position, no irregular wear on rocker or shaft and side plugs are still intact

5.put lifter back in hole, put bent pushrod back in place and noticed if i pulled the cup back up to how far out of the pushrod it was sitting when i pulled valve cover (about 1/2 inch out of pushrod) it fit right up on the ball of the rocker. camshaft in this posistion for this cylinder just happens to be on the base circle where the valve would be shut

Now i dont want to assume because this is a critical problem and i need to go over every possible thing but could it be the 440 source 3/8 pushrod just flat out failed me? idk im no expert on valvetrain geometry but when i first assembled the motor everything seemed within reason, small sweep, pretty well centered on valve stem... of course it could be better but other than possibly needing more clearance for pushrod, or geometry issues i didnt see, i dont think theres anything else to it than maybe where the pushrod and the cup mate there was a failure with the higher rpms

any suggestions i may have missed?
 
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