How can i improve my oil pressure in my 360 magnum

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maca

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Hey all
I have a small block magnum that has had bad oil pressure for years. I put in a mellings high volume oil pump a couple of years ago but it didn't help. If I run fully synthetic engine oil I have around 10 PSI at idle. It does go up as the RPM goes up and I stripped the engine down in the past and the bearings haven't been worn badly but I'm rebuilding it soon and will be spinning it higher than normal so i thought while its out I'll try and improve the pressure.
Any mods that help?
 
Crank and rod bearings sounds like to me, that's where we lose oil pressure I believe, but let a good tec jump in and help
 
Yes I checked the oil gauge a while ago. I own another magnum engine in another car which has better oil pressure but it's still not great. Around 30 psi at idle
 
Yes I checked the oil gauge a while ago. I own another magnum engine in another car which has better oil pressure but it's still not great. Around 30 psi at idle
at idle!! I would think that is great oil pressure
 
You say the bearings "looked good". Did you at least use Plastigage? Bearings are available in undersize, by the thousandth, if need be.
 
You say the bearings "looked good". Did you at least use Plastigage? Bearings are available in undersize, by the thousandth, if need be.
I had the machine Shop check all the clearances and I used plastigauge when I originally built the engine.
I remember shimming my oil pump on another 6 cylinder engine years ago. Perhaps I need to do the same on this engine
 
Hey all
I have a small block magnum that has had bad oil pressure for years. I put in a mellings high volume oil pump a couple of years ago but it didn't help. If I run fully synthetic engine oil I have around 10 PSI at idle. It does go up as the RPM goes up and I stripped the engine down in the past and the bearings haven't been worn badly but I'm rebuilding it soon and will be spinning it higher than normal so i thought while its out I'll try and improve the pressure.
Any mods that help?

Check to see that all of the oil galley plugs have been installed...

I had a machine shop leave out the ones that go under the cam thrust plate..

Also check the one in the rear of the lifter galley near/under the distributor hole...

The way that I found my oil pressure problem was under the advice of Ken Neve who told me to spin the oil pump and gradually tear into the engine... Look for where oil is gushing out when you spin the oil pump with a priming shaft, and that is where you are loosing pressure...

Good luck...
 
'Shimming the pump' only increases the pressure relief spring's pressure. It typically does little or nothing for the idle pressure.

Realize that at cool temps (like at start up), synthetics will be thinner than standard oils so will show lower cool pressures. At temps like 60F, the lower oil weight rating is not accurate, that 'cold' weight rating is measured at 104F.

What weight of synthetic is this?
 
Hey all
I have a small block magnum that has had bad oil pressure for years. I put in a mellings high volume oil pump a couple of years ago but it didn't help. If I run fully synthetic engine oil I have around 10 PSI at idle. It does go up as the RPM goes up and I stripped the engine down in the past and the bearings haven't been worn badly but I'm rebuilding it soon and will be spinning it higher than normal so i thought while its out I'll try and improve the pressure.
Any mods that help?
There are no mods to increase oil pressure. There is a standard and hi volume oil pump. That’s it.

Otherwise, the way to normal or higher pressures are tighter clearances. If your current engine hasn’t been previously rebuilt, then it is worn out with high clearances.
 
When this engine was "stripped down for an inspection" was the camshaft removed? Did someone inspect the cam bushings for delamination? Missing bushing material= bad oil pressure too!
 
Hey all
I have a small block magnum that has had bad oil pressure for years. I put in a mellings high volume oil pump a couple of years ago but it didn't help. If I run fully synthetic engine oil I have around 10 PSI at idle. It does go up as the RPM goes up and I stripped the engine down in the past and the bearings haven't been worn badly but I'm rebuilding it soon and will be spinning it higher than normal so i thought while its out I'll try and improve the pressure.
Any mods that help?

There are no mods to increase oil pressure. There is a standard and hi volume oil pump. That’s it.

Otherwise, the way to normal or higher pressures are tighter clearances. If your current engine hasn’t been previously rebuilt, then it is worn out with high clearances.


Mellings uses the 72 psi spring in all of their oil pumps... I called them once and they told me that...

MP uses a 55 psi spring typically and you can buy the high pressure spring kit to put the 75 psi spring in...

Changing the Mellings to the MP high pressure spring is not worth the effort to gain only 3 more psi... :realcrazy: :BangHead:
 
Hey all
I have a small block magnum that has had bad oil pressure for years. I put in a mellings high volume oil pump a couple of years ago but it didn't help. If I run fully synthetic engine oil I have around 10 PSI at idle. It does go up as the RPM goes up and I stripped the engine down in the past and the bearings haven't been worn badly but I'm rebuilding it soon and will be spinning it higher than normal so i thought while its out I'll try and improve the pressure.
Any mods that help?

I strongly second this by Krazykuda

"Check to see that all of the oil galley plugs have been installed...

I had a machine shop leave out the ones that go under the cam thrust plate..

Also check the one in the rear of the lifter galley near/under the distributor hole..."
 
I strongly second this by Krazykuda

"Check to see that all of the oil galley plugs have been installed...

I had a machine shop leave out the ones that go under the cam thrust plate..

Also check the one in the rear of the lifter galley near/under the distributor hole..."
If the threaded plug is left out at the distributor area at the left rear lifter galley, the hydraulic lifters on the left side of the engine will not pump up and it will clatter like heck at idle. If they arent doing that, really no need to check, however you still can easily if you want to. Pull dizzy and stick an inspection mirror down in there
 
Wherever a colored line meets a moving part, there will be an oil "leak". Your pressure gauge reads what is left over, after all the leaks are summed. This pic appears to be a SBC, but it don't matter much.
There is one cup-plug that is rarely mentioned and that is the one that is installed right near the rear main cap, that separates oil-flow to and from the filter. If it is not driven in all the way, I suppose it could restrict flow , and the upstream pressure would read low. In the second picture, the bottom left inset shows this area, but I can't see the plug. It should be in the little black smudge at the bottom of the pic. The cup hits a step in the passage that stops it,when it is installed correctly.
Sorry about the postage-stamp,at the bottom, I can't get rid of it

If you are gonna spend a lotta time at over 6000rpm,there are a few things you should do to your oiling system that are cheap insurance to help your engine live. I lost two engines before I figured it out. The mods are detailed in the tech-forum. Some of us on FABO after the mods, are good to at least 7000rpm
Extra oil capacity is also recommended. You can go deeper, the preferred way, or if a streeter, the Milodon roadrace pan has a trapezoidal shape that drops to just below the K-frame about an inch; use it with the matching larger diameter oil-pick-up. I think it is spec'd as a 7 quart. If you recalibrate your stick, you can run it at 6 or 7 quarts on the street, putting your oil well away from the crank. Install the stick BEFORE the pan goes on, to see where the calibrated end goes. I had to drill a hole in the windage tray to let it pass thru, instead of it going sideways and skidding along the tray. Some guys have experienced the stick getting caught up in the moving parts, and the end turned into a pretzel.
I highly recommend you fabricate a lil skid-plate for that pan, cuz welding/patching the pan in-situ, for me,was a temporary fix,lol.

SBCOilingnew.png

Aengine.jpg


upload_2019-2-3_10-27-23.jpeg
 
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