Low & High Pressure Oil Pressure

Keith Browning · June 2, 2015

Believe it or not I have never run into this before. A 2004 F450, 100,000 miles, build date 1/26/2004 with a reported lack of power.I road test it and yep, it loses power when you get on it and once it's hot, the oil pressure gauge flat lines. P2290 and P2291 in memory. I road tested it and at full throttle, it bogs down and IPR goes up to 84% and ICP drops to a constant 484 PSI. Base oil pressure is 4PSI @ hot idle. After cold soak it cranks a good 10-15 seconds and then starts. I also pulled the oil filter after an overnight sitting and it appeared as the housing was full. So I am likely losing pressure somewhere and the High Pressure system is losing prime on a cold soak.Decided to pull out the LPOP to inspect. The gears, front cover and pump cover look decent with some minor scoring which I expect with high mileage. No gouges or signs of debris. Measurements are well inside specification The regulator slid right out and has no scoring at all. So I am looking elsewhere. I don't suspect base engine damage at this time.I read through a bunch of posts here. It seems as though all three of my symptoms fit the missing ball concern... there are several posts and pictures about a ball falling out of the HPOP on 03-04 engines. Does this affect ALL of the early type pumps? I am considering pulling it out for a look. Opinions?

mchan68 · June 2, 2015

From my experience, it seems to be the late build pumps that ball falls out of. With what you have, at this point it wouldn't hurt to air test it at operating temperature. At the very least, air back feeding into the oil filter housing would be the basis to condemn the pump. On a couple of the early style pumps I've replaced, there is a bolt there in lieu of the ball bearing so the replacement part is updated. It wouldn't hurt to check the standpipes and dummy plugs as well for good measure, even though they seem to fail only on the '05 and up style engines.

Keith Browning · June 2, 2015

Only thing Mike, is that I have never seen a "bad" pump cause a LPOP pressure concern. But, I have never run into one of the missing ball deals. It also really does not behave like it has a standpipe/block off leak. I dunno, it just doesn't fit that scenario, but you're right I should not rule that end of it out though.

Steve Mutter · June 3, 2015

The one I had was a 2004 with icp sensor in the rail, came in for the oil pressure light on. Removed the high pressure oil pump and found the ball missing. Put a reman pump in and it was good after that. My oil pressure was low too when I first checked it, I think it only takes 8psi to put the needle in the middle of the oil pressure gauge.

Keith Browning · June 3, 2015

Low oil pressure specification in the WSM is 12 @ hot idle. I wonder what the "typical reading" is. Steve, this is a late early build with the ICP on the right valve cover and has a cast iron HPOP cover.

Matt Saunoras · June 3, 2015

I have not personally experienced this but deal with a fleet that recently had this happen.

I wasn't told how the truck ran but that it's losing oil pressure. This was after they put a sending unit and pigtail in it. Got them to order a pump, inspected the core when it came back and the ball was missing. This was a later build wavy rail 2004.

I have read that this ball "failing" out is actually caused by a temporary reversal in flow causing high pressure oil to push backwards toward the reservoir which blows the ball out. I don't know if this is true or not. I have also read instances of no starts with the ball missing where guys have tried to tap and plug their old pump and the truck still wouldn't start. This supports the idea that something is wrong internally with the pump.

gengor · June 3, 2015

Keith, I have a very similar concern on my hands right now. 2004 e450 with icp on the side and a cast cover. This one is a no start, low icp codes. I have no low side oil pressure, took the filter off and no oil flow out of the housing while cranking. Removed the low pressure pump, pump cover and front cover show no wear, pump looks good, low oil pressure regulator moves freely in the bore. I am wondering if I have a oil pickup tube problem or if the oil cooler is plugged. The oil filter comes after oil cooler according to the oil flow diagram.. also should I have any oil flow coming out of the low oil pressure regulator while it removed? any ideas would be appreciated.

Also, Keith, I have seen the missing ball on the HPOP to cause low side oil pressure light to flicker on while it was running with a severe lack of power.

mrbudge · June 3, 2015

I have seen 7.3 with the oil pump pickup screen plugged with silicone lose LP oil pressure then lose power on hard accell. It appears that under load the HP system would demand more oil than the plugged screen would allow through. Has this unit had an oil pan replaced?

lmorris · June 3, 2015

I have seen 7.3 with the oil pump pickup screen plugged with silicone lose LP oil pressure then lose power on hard accell. It appears that under load the HP system would demand more oil than the plugged screen would allow through. Has this unit had an oil pan replaced?

This would have a rubber gasket. No silicone to plug up the pick up.

Keith Browning · June 10, 2015

Thanx Gents. This and previous posts pointed right to this:

ktmlew · June 11, 2015

There are some pictures somewhere of one of those torn down. A section of the pump that is supposed to be fixed spins in the case which diverts flow. That pushes the ball out.

Keith Browning · June 11, 2015

There are some pictures somewhere of one of those torn down. A section of the pump that is supposed to be fixed spins in the case which diverts flow. That pushes the ball out.

THAT explanation I would believe. I have the new pump and the ball is staked pretty good but I see no evidence in the old pump of such measures. These pumps do commonly fail from he drum housing spinning in the case and I can see how it might cause a reverse flow condition. Personally, I don't see how these engines can even run with that happening. Also, that bore being open like that is a HUGE leak and I am surprised that it does not draw air. This tells me that the LPOP is capable of some decent volume it can feed the engine and that pump and overcome the leak.

Here are the pictures of the pump and swashplate housing that spun:

Posted Image

DieselD · June 11, 2015

I have had several that run and others that wont with the ball missing. If I was a betting man I would say it wouldnt be possible for it to run with that leak caused by the ball

Keith Browning · June 11, 2015

Ahhh, but it did! And by the way, a new pump corrected all oil pressure, long crank and power loss issues.

Matt Saunoras · July 31, 2015

The new pump ball is staked in for sure but like we stated before I believe something is pushing the ball out of the low pressure side.Got a few pics of new vs old. This old pump definitely has something wrong inside, it does not spin smoothly and has one spot that it binds up hard. The truck would start and idle but make only the bare minimum ICP with IPR maxed at 84%.I haven't paid too much attention to old pumps but you can tell this ball is on its way out. I also noticed too that the large snap ring on the old pump has shifted from it's original spot.