Newly built 440 with low oil pressure

[Jon Lowell]

Sounds like a stock oil pump. Look for a part number on it if there's no record of what you have.

Easy to Install a High volume pump.
There was a interesting engine masters they found no hp loss in going to larger pump.

It’s a stock melling pump. I’m going to put a high volume on it

 

[diesel_lv]

Here's a factory gauge at 222° after a 30 mile drive in 120° weather and then idling for 10 minutes w the a/c on
During the drive it never got over 182°

 

[Jon Lowell]

Are they mechanical gauges or electrical? I prefer mechanical for oil, more accurate. MO

Aftermarket mechanical, just noticed it’s leaking on the engine fitting maybe that is playing a part.

 

[440 PHIXX]

You could just change the spring in the pump. They used to be available from Chrysler, but probably on the internet. I did that to a stock 440 with the OG oil pump and it had 50psi at idle, and 80psi above 1500RPM.

 

[Bee1971]

Sounds like a stock oil pump. Look for a part number on it if there's no record of what you have.

Easy to Install a High volume pump.
There was a interesting engine masters they found no hp loss in going to larger pump.

Thanx - Found this

Engine Masters - Oil Pump Pump Off
440



They used stock Melling oil pumps, Stock, High Pressure, High Volume, and a race Billet (Milden) one. The only pump that lost HP was the race Billet pump. The stock Melling High Volume pump increase volume (4.9 vs 6.2 gpm), increase pressure at idle 18 psi over stock pump (31 vs 49) and 22 psi at peak flow (54 vs 76) over the stock pump and didn't use anymore horse power.

 

[Jon Lowell]

You could just change the spring in the pump. They used to be available from Chrysler, but probably on the internet. I did that to a stock 440 with the OG oil pump and it had 50psi at idle, and 80psi above 1500RPM.

Thanks for the info.

 

[Jon Lowell]

Thanx - Found this

Engine Masters - Oil Pump Pump Off
440



They used stock Melling oil pumps, Stock, High Pressure, High Volume, and a race Billet (Milden) one. The only pump that lost HP was the race Billet pump. The stock Melling High Volume pump increase volume (4.9 vs 6.2 gpm), increase pressure at idle 18 psi over stock pump (31 vs 49) and 22 psi at peak flow (54 vs 76) over the stock pump and didn't use anymore horse power.

View attachment 1347787

Awesome that’s great info. I’m definitely doing a high volume pump.

 

[440 PHIXX]

Thanks for the info.

You don’t even have to remove the pump. The retaining nut is on the side. I did it in a 130k 440, that still had great cylinder pressure.

 

[steve340]

Nick from Nicks Garage did a video about the Melling pump partially blocking the oil hole in the block restricting oil flow from the pump to the engine.
It would pay you to check this I think.

 

[Nxcoupe]

I just saw who rebuilt your engine, they have a poor reputation here locally. Do the spring upgrade, I used to do that all the time on higher mileage engines.

 

[Jon Lowell]

I just saw who rebuilt your engine, they have a poor reputation here locally. Do the spring upgrade, I used to do that all the time on higher mileage engines.

They did a great job on the engine it runs
Strong. Very stout. We used a stock oil pump. I’ll probably do a new high volume
Or spring replacement. Thanks for the info

 

[BSB67]

1) your oil pressure seems lower than it should be. You should find out why. It may, or may not be an indication of a problem. You need to get the bearing clearances and bearing type.
2) your leaking fitting is not the reason for the low oil pressure.
3) a high volume oil pump will help increase idle pressure.
4) a high pressure spring will not help low idle oil pressure.
5) lower engine temp and higher viscosity oil will help.

 

[RJRENTON]

You could just change the spring in the pump. They used to be available from Chrysler, but probably on the internet. I did that to a stock 440 with the OG oil pump and it had 50psi at idle, and 80psi above 1500RPM.

Note that just changing the high pressure relief valve spring WILL NOT increase the volume of oil delivered by the pump....only the maximum pressure developed. IF the engine's oil volume required is higher due to more bearing or lifter bore leakage, the pump WILL NOT achieve the higher relief valve pressure setting, and the pressure will remain the same. The ONLY way to reduce volume requirements is: reduce bearing clearances and lifter bore leakage (if this is a leakage point) OR supply a HIGHER oil volume to overcome the leakage losses. Ultimately, the real fix is to decrease the bearing (or lifter bore clearance) leakage by reducing clearances.....if this the cause of the low cooperating pressures.

IMO....switch to the HIGH VOLUME PUMP, its the "EASIEST" THING TO DO. WHEN DOING SO, REMEMBER TO INSTALL THE O-RING ON THE PUMP'S DRIVE BOSS, POUR SOME OIL INTO THE SUCTION INLET AND TURN THE PUMP DRIVE WITH AN ALLEN WRENCH TO DISTRIBUTE THE OIL TO THE ROTOR AND CAM RING (internal to the pump to help the pump pick up it'S prime) and MAKE SURE THE PUMP TO ENGINE GASKET IS INSTALLED IN THE CORRECT ORIENTATION. INSTALL THE PUMP, ALIGNING THE PUMP TO THE PUMP DRIVE SHAFT AND INSTALL THE MOUNTING BOLTS, ONE AT A TIME B4 TORQUING THEM TO SPECS. TRY AND PARTIALLY FILL THE OIL FILTER B4 INSTALLING, DOUBLE CHECK YOUR WORK B4 TRYING TO START.
You may also consider using a heavier weight oil......but....that's up to you..... let us know how you make out.......good luck........
BOB RENTON

 

[Jon Lowell]

Note that just changing the high pressure relief valve spring WILL NOT increase the volume of oil delivered by the pump....only the maximum pressure developed. IF the engine's oil volume required is higher due to more bearing or lifter bore leakage, the pump WILL NOT achieve the higher relief valve pressure setting, and the pressure will remain the same. The ONLY way to reduce volume requirements is: reduce bearing clearances and lifter bore leakage (if this is a leakage point) OR supply a HIGHER oil volume to overcome the leakage losses. Ultimately, the real fix is to decrease the bearing (or lifter bore clearance) leakage by reducing clearances.....if this the cause of the low cooperating pressures.

IMO....switch to the HIGH VOLUME PUMP, its the "EASIEST" THING TO DO. WHEN DOING SO, REMEMBER TO INSTALL THE O-RING ON THE PUMP'S DRIVE BOSS, POUR SOME OIL INTO THE SUCTION INLET AND TURN THE PUMP DRIVE WITH AN ALLEN WRENCH TO DISTRIBUTE THE OIL TO THE ROTOR AND CAM RING (internal to the pump to help the pump pick up it'S prime) and MAKE SURE THE PUMP TO ENGINE GASKET IS INSTALLED IN THE CORRECT ORIENTATION. INSTALL THE PUMP, ALIGNING THE PUMP TO THE PUMP DRIVE SHAFT AND INSTALL THE MOUNTING BOLTS, ONE AT A TIME B4 TORQUING THEM TO SPECS. TRY AND PARTIALLY FILL THE OIL FILTER B4 INSTALLING, DOUBLE CHECK YOUR WORK B4 TRYING TO START.
You may also consider using a heavier weight oil......but....that's up to you..... let us know how you make out.......good luck........
BOB RENTON

Thank you very much. I ordered a new high volume pump. I’m going to change the break in oil tomorrow as well as filter and go with a slightly heavier weight.
It has rotella 15-50 with sink additive now

 

[440 PHIXX]

Note that just changing the high pressure relief valve spring WILL NOT increase the volume of oil delivered by the pump....only the maximum pressure developed. IF the engine's oil volume required is higher due to more bearing or lifter bore leakage, the pump WILL NOT achieve the higher relief valve pressure setting, and the pressure will remain the same. The ONLY way to reduce volume requirements is: reduce bearing clearances and lifter bore leakage (if this is a leakage point) OR supply a HIGHER oil volume to overcome the leakage losses. Ultimately, the real fix is to decrease the bearing (or lifter bore clearance) leakage by reducing clearances.....if this the cause of the low cooperating pressures.

IMO....switch to the HIGH VOLUME PUMP, its the "EASIEST" THING TO DO. WHEN DOING SO, REMEMBER TO INSTALL THE O-RING ON THE PUMP'S DRIVE BOSS, POUR SOME OIL INTO THE SUCTION INLET AND TURN THE PUMP DRIVE WITH AN ALLEN WRENCH TO DISTRIBUTE THE OIL TO THE ROTOR AND CAM RING (internal to the pump to help the pump pick up it'S prime) and MAKE SURE THE PUMP TO ENGINE GASKET IS INSTALLED IN THE CORRECT ORIENTATION. INSTALL THE PUMP, ALIGNING THE PUMP TO THE PUMP DRIVE SHAFT AND INSTALL THE MOUNTING BOLTS, ONE AT A TIME B4 TORQUING THEM TO SPECS. TRY AND PARTIALLY FILL THE OIL FILTER B4 INSTALLING, DOUBLE CHECK YOUR WORK B4 TRYING TO START.
You may also consider using a heavier weight oil......but....that's up to you..... let us know how you make out.......good luck........
BOB RENTON

The thread title said low pressure.

Mopar Performance BIG Block Oil Pressure Relief Spring P4286571 383 426 440 BB | eBay

 

[Jon Lowell]

Going to reiterate the bearing clearances, if it was set up loose, it will run a bit low psi. What is your idle rpm? What is 55mph rpm. 10 psi per 1k rpm is ok, depending on clearances. Some are much higher w tighter clearances.
As for temps, too many shadetree mechanics who don't understand a thermostat. A 180 will stay closed to 180 to allow engine to warm up. It will be fully open at 195° and will run once stabilized around 195-210. Mopars in the 60's came factory 180° n 195° t-stats. A 195 will open at 195 n fully open at 210°. If your cooling system is stock, nothing at all wrong w your temps.

Sorry for my ignorance I purchased the car with the motor in it. I have the slips for what was done. But by no means do I know what the clearances are or supposed to be. Sorry this is all I have.

 

[Sam69sat]

I would also open the new high volume pump and make sure it's clean of machining debris. I can't remember where but i saw a video of someone with a brand new pump and it was full of metal shavings. Quality control is bad these days.

 

[Geoff 2]

I would NOT use a HV oil pump. The BB Mopar has one of the worst pump inlet/intake designs in Detroit. Long pick up, numerous bends. Right angle drillings in the block with sharp edges. Which all adds up to restrictive oil flow. Chr saw a problem& did something about it with the Hemi by enlarging the p/up tube diam.
Adding a HV pump on it's own might cause air to be drawn in at high rpms. Brgs do not like air......

Your OP is a little low, but not dangerous. I believe there is a simple fix if you are worried about it. Production oils are friction modified. In laymans' terms the viscosity of FM oil sh*ts itself when it gets hot; it gets thin; it can get good mileage for EPA testing. In my country, I can buy oil that states this on the label: non- friction modified. I do not think you have this on the label in the US. These oils will have 5-10psi more idle pressure over the same viscosity FM oil.
I would think racing oils in the US are not FMed. So I would try some 15w/50 race oil & see what it does for OP.

 

[Fran Blacker]

With a HV pump oil pan capacity is important, 7qt.

 

[Runcharger]

Yep: If some Chevy guy crossdrilled the crank along with big bearing clearances a HV pump can pump all the oil up top at high RPM using a small pan.