rawbee

As the title say. First time start up was Wednesday. Had zero oil pressure at that time. I then started it again for about 10 seconds still no pressure. Next day I dropped oil pan and checked that Oring for pick up tube. (Attached photo of pick up tube) made sure it wasn't pinched and re installed. I packed the inlet for pickup tube of the oil pump with petroleum jelly then installed the tube. Started back up still nothing. Checked some other stuff found my oil filter re-locator to be backwards. Swap lines and BOOM oil pressure. But I only have 10 psi at idle. I rev up a bit and I have 20-30. The highest I have seen was 40psi but I have a constant 10psi. I have zero ideas of what to do at this point. I have a twin turbo ls. I actually took the return line off both of my turbos and I have a steady stream of oil coming out of them. I put 5w30 in it. Not sure if I should drain oil and put 10w30 and change filter. Not sure if maybe my filter is collapsed from the reverse flow when the lines were switch. Only other thing I could think is bad oil pump. This is a fresh build. It's a brand new melling oil pump. Everything is brand new nothing used. Someone please give me some info on what I could be over looking. This is killing me. Appreciate any help in advance.

06tx4.8

iTrader: (19)

if its a new motor, u need to make sure the bar bell is installed behind rear cover. if its not, thats your problem

rawbee

Barbell is there I installed new one myself.

Inspector12

iTrader: (29)

10lbs at hot idle? wouldn't bother me too much, but lower than that would concern me. Plus is that with the factory gauge or a manual gauge? And def. run something such as Rotella 15-40 for a turbo setup or another specific race oriented oil. GL!

oscs

iTrader: (19)

I don't care what anybody says 10psi at hot idle is not enough oil pressure. There is something wrong. A healthy motor should be seeing at least 20psi. Did you blue print your motor? The difference between 5w30 and 10w30 is nothing unless your trying to start the car in freezing temperatures. Throw a new filter on there for good measure. Take your old one off and cut it in half. If you see gold flakes than your bearings are fried and that's why you have no oil pressure. You also need to verify your mechanical and electrical oil pressure gauge is reading the same. Also you say you can't get past 40psi oil pressure? I'm assuming that's at idle with your revving it up in neutral?

rawbee

yeah that's at idle and revving up. Cold start I'm getting 20psi as I let warm up I get about 15. I'm using a mechanical gauge not electric. I am gonna get another mechical tomorrow and see. I have a aftermarket gauge I am installing tonight it is electric. But I just did oil change and out 10w40 and new filter. When I drained oil it was a bit metallic but I feel like fresh start up it should be normal.

oscs

iTrader: (19)

You defiantly need to verify electric vs mechanical. My mechanical gauge takes almost 10 seconds to get up to 45-50 PSI cold start but the transducer reads 45-50 PSI immediately. 15 is better than 10 but still low. The thing you need to be more worried about it is if you get an increase in pressure with RPM. General rule of thumb is 10PSI per 1000RPM. So if your shifting at or above 6k you should have around 60PSI. Metallic is normal, it's the "gold" flakes you need to be worried about.

Scoggin Dickey

iTrader: (34)

What engine setup do you have? What's it out of, what valley cover and oil pan do you have? What modifications did you make to the engine? Considering the truck pickup tube, was this a truck engine that had DOD and you removed the DOD?

rawbee

it's does increase. I actually tried another gauge. Idle about 10. About 4k is 35-40psi. I'm running wires as we speak for electric gauge.

rawbee

it's a truck 5.3l bored to 5.7l bore 3.905. Cx racing front sump oil pan. Nissan 240sx LS swap pan. Stock valley cover. It's a twin turbo running twin t76's. And not sure what DOD is. Lol. But it's has a melling m295 brand new oil pump. With new rod bearings cam bearing and main bearings. Everything is new. Fresh build.

rawbee

Also double roller timing chain

oscs

iTrader: (19)

Nice car

1-87 chevy

iTrader: (15)

maybe a spun cam bearing!!

rawbee

I think the only other thing I got is maybe a factory defect oil pump? I honestly don't know what to do next. Like no idea what I could be over looking

oscs

iTrader: (19)

I'm assuming your electric gauge Mirrors your mechanical?

Scoggin Dickey

iTrader: (34)

Is your valley cover flat, or does it have a bunch of raised passages cast into it?

Ari G

iTrader: (25)

You dont need to worry about the pressure as 10psi is fine for no load idling,any built motor for Forced induction is going to have lower then stock oil pressure at idle because of increased bearing clerance and fixed volume per rpm

You have a std volume oil pump,a 10296 pump is the higher volume pump that would put more pressure at idle and lower rpm but same limit of peak psi

The pressure dose not sepperate the friction surfaces but the oil film,as long as you have pressure the bearings are full of oil and it can create the boundry layer to float on,it just needs to increase as rpm rises

You are going to see allso lower pressures from expansion if you have aluminum block and lifter bore wear if it is used vs cast iron on same clerances

You can use 15-40 or 20-50 to get it up,that is actually what manufacturers specify when they cant say if the car will be in Alaska Winter or Texas Summer as they reccommend 5-30w in temps of 0-75°F and 20-50w for 75°F and up in general

Cut open your filter to see if it has alot of metal shavings in it and if your oil temps are high,that is an indication you have a spun bearing

oscs

iTrader: (19)

The basic principals of bearing coating is correct as you have explained but you are wrong about pressure not separating the friction surfaces. The more load that is applied, the more pressure needed in order to maintain your pillow of oil between the two surfaces. This is basic stuff. As many motors as you've put together and your going to tell this guy 10psi hot idle is ok? Will it work? Sure becuase its under no load. Is it anywhere near desirable? Absolutely not. My freshly built boost built motor hot idles almost 20 psi more than this and you can believe my tolerances are loose. This is with 15W30.

OP I wish I had more advise for you but I stick by my guns.10psi hot idle is unacceptable in my book.

01Z0H6

iTrader: (63)

*this...

playtoy

iTrader: (5)

Anyone else see the problem with the new motor being started twice with no oil pressure. I'm willing to bet the bearings are toast already.