Stroker2112

Guys,

Whats the best way to make sure you have oil pressure before you fire up a brand new LSx engine?....I installed a brand new 408....but am having a serious concern that the oil pressure isn't there. The gauge reads 0! after 2 startup of 30 seconds or so...nothing!.....so is there a way I could get the oil going? Could I force oil through the oil pressure sending sensor (remove it and pump oil in there)?


Any advice will be greatly appreciated!!!!

Stroker2112

purdueranger

iTrader: (11)

What I have seen done alot is pull the fuse for the coil packs and the fuse for the fuel pump and just turn the car over until you get oil pressure. This is what my roomate has been doing to his camaro after it sits all winter.

Ramairbird

iTrader: (17)

When I did my motor I dumped oil into the pump and pushed oil into the oil pres. switch port. I still had to start it before it would show on the gauge, sometimes cranking is not enough on a fresh build. I also filled the filter w/ oil before starting. My concern with yours is the oil pick up tube o-ring. It happens all the time that it gets pinched, it needs to be on the tube 1st before the tube is installed in the pump.Good luck.

Slowhawk

iTrader: (12)

I just load the engine with oil when building it and start it right up.Priming can wear the bearings more.Ussually oil pressure goes up in 2-3 seconds after the first start.

lilbuddy1587

iTrader: (1)

I'd take apart the oil pump and pack it with grease to help with vaccum. Then I'd fill the oil filter with oil as stated above and start her up.

Cop Car

iTrader: (14)

coated everything with STP and then when i have it in the car im going to pull both wires going to the coil packs and give it a couple of cranks then start it.

Steve Bryant

iTrader: (1)

Stroker2112,
Here are the things that I would check:
1. Make sure that the screened inlet of the oil pickup has no obstructions.
2. Make sure that you have the proper o ring for the pick up tube. There are two o rings, one is blue and one is black (I believe). Only one will fit your pump and pick up tube properly.
3. Make sure that the O Ring on the oil pump is properly installed. Not pinched and the oil pick-up tube with lubricated o ring must be pulled into the oil pump before tightening the bolt. Do not pull the tube into the pump with the bolt.
4. Make sure that the oil pump is flush where it mounts to the block on the driver's side
5. Make sure that the main galley oil plug is in place. It should have some blue Locktite on it when it is driven in.
6. Make sure the rear dumb bell plug is installed in the rear portion of the main oil galley. The o ring on the dumb bell must point toward the rear.

Other things to consider:
1. Is the oil filter properly installed and filled with oil?
2. What are your bearing clearances (main, rod and cam)?
3. The pressure regulator in the oil pump (spring and piston assembly) may not be functioning properly (this is unlikely).
4. I would not pack the gerator with grease. The grease will fill the cavity where oil can be drawn into the pump and will prevent proper pumping action.

All my best,

Steve

Slo_240sx

iTrader: (17)

Great helpful list. I would definately NOT pack the oil pump with grease as said.

Ferocity02

iTrader: (60)

I simply put in as much oil as I could through the oil pressure sending unit hole. The assembly lube will keep it from leaking out through the bearings into the pan. I think I got about 1/2 quart through this hole. When I started it, I had oil pressure within 2-3 seconds. Make sure to fill the oil filter with oil too before installing it. I wouldn't prime the engine with the starter. It's hard on the starter motor and doesn't spin the motor fast enough to pump enough oil before the assembly lube is gone from the bearings.

slowride

iTrader: (3)

I just turned the engine over without the plugs in and the fuel injectors disconnected. Had oil pressure in a few seconds.

Stroker2112

OK, so I'll fill the oil filter w/oil(didn't do this initially)...and fill as much as possible into the pressure sending unit opening...hopefully this will get the pressure going. I did take special care during the build to make sure the O-ring on the pick-up/pump was installed correctly...and also know that the back dumbell galley plug is there. 99% sure the front oil galley plug is there...don't know why it wouldn't but if things don't get better thats the 1st place I'm looking.

Should I disconnect the fuel and spark before starting it again?...

Stroker2112

Ferocity02

iTrader: (60)

You'll be amazed how much oil you can get in the filter, it sucks it right up. Takes probably 5 minutes the fill the filter because it takes some time to soak in. Once you're ready, disconnect the coil packs and pull the fuel pump fuse and and crank it for a few seconds. Then plug everything back in and you should have oil pressure within a few seconds. If not... well

orangeapeel

iTrader: (18)

Hopefully!

DanZ28

iTrader: (5)

If you ran it for 30 seconds twice and still have no oil pressure, I would start thinking about looking at stuff internally. Regardless of priming or filling the filter with oil, it ran more than long enough (a full minute) to to get oil pressure IMO. Maybe check out the sending unit itself and make sure it is plugged in and working. Hope all is well, good luck!

Dan

ShevrolayZ28

iTrader: (4)

You could have a look inside a valve cover to see if oil made it up the pushrods.

hondakiller

iTrader: (3)

Since it hasn't been mentioned I thought I'd add it but did you check the oil pressure sensor on the intake?

Stroker2112

OK
I'm going to prelube oil into the filter and through the Oil pressure sending unit tonight(and disconnect the coil and fuel pump fuse) before cranking it over a couple of times ....and then try it again.... I should know within a few seconds if its going to work...right?....if I don't see the oil gauge move at all, then I'll know its an internal problem.

BTW- What does an engine sound like right before it siezes?...(hope I don't find out...)

Stroker2112

ShevrolayZ28

iTrader: (4)

Unfortunately, the stock oil gauge will not show a reading, the gauge is dead when you crank the key. My car would not pump oil by turning the engine over. I've tried it for around 20-30 seconds with the spark plugs removed, the fuel pump disabled, the coils disconnected, and I saw NO oil circulation, no oil reached the rockers. The oil pump will not pick up the oil from the pan unless it's spinning much faster, i.e. with the engine running.

If you turn it over without starting it you risk creating some wear. Your only lubrication will be what was applied during assembly.

Try starting it IMO. If you don't get oil pressure within 5 seconds there is a problem and you should shut it down.

Stroker2112

ShevroletZ28,

Thank you for the valuable response!...that will save extra work and perhaps failed expectations tonight when I go to figure everything out!

Curious to know if you or anyone has experienced this..... if the MAF sensor isn't plugged in at the time of startup, will that have an affect on the oil gauge?...


Stroker2112

Steve Bryant

iTrader: (1)

If the MAF is not plugged in, you will get a "check engine" light, but it will have no effect on the oil pressure reading. A MAF failure (or absense by not being plugged in) will not prevent the engine from starting and running. I will simply revert to the speed density mode and work off the volumetric efficiency tables based on manifold absolute pressure (MAP) and engine speed (RPM). I agree with ShevroletZ28, try to start the engine. Run it for five or eight seconds or so. If you don't get oil pressure, shut down and investigate. Hopefully, you have not done any damage yet, but you've gone about as far as you dare before you really find out what is happening.

Steve