strange oil pressure cranking problem

[suprra_girl]

i've noticed that you guys can crank your cars and get an oil pressure reading on your gauges, now prior i could understand not getting it as we have digital gauges and they are all off while cranking. Now i have a prosport analogue gauge and i still don't have oil pressure showing up on the gauge.
I pulled off my oil feed to the turbo and that will not get pressure on cranking.
I also noticed that my sump was still full capacity and it shouldn't be as the oil should have gone to my filter/thermostat/cooler which should lower the level decently.

Its not just mine i've had this on, i've had it on 1g's, 1j's and 7m's be it analogue or digital gauges (90% of 1g's & 1j's came with analogue)

So why do you guys get pressure on cranking and we don't?
I"m going out to buy a syringe tomorrow so i can feed my turbo manually before i actually start it.

Oil pump is mechanically driven so is it purely just not enough engine speed at cranking to get enough pressure up? (i have heard from others that they can get pressure up by manually cranking it, so whats going on lol)

p.s... yes

before i actually start it

you heard right. Tomorrow it will be started if all goes to plan and i'll grab a video

 

[CyFi6]

if you think about it, if youve got approx. 5 psi at 750 rpm i wouldnt expect much if any at ~300-400 rpm. Even if theres almost no pressure you should still have flow though.

 

[IJ.]

I pack my pumps with Castrol LMM grease when I assemble them.

This creates the initial suction allowing the pump to prime.

I see 20>25 psi cranking long before the motor fires.

 

[suprra_girl]

but for a stockish rebuild what i'm seeing is normal?
Generally with the other cars they get pressure as soon as they're running tho... i'm assuming mine will too haha

 

[IJ.]

You could try using a 1 litre Oil bottle with the pop up nozzle and force some Oil backwards through the Hose into the pump to prime it up.

 

[suprra_girl]

Is there definitely a need for this or should i just fire her up as i have many supras? i'm super uber sure i'll have pressure, my reconditioner is awesome hehe

 

[IJ.]

I won't start a motor that can't make pressure cranking.

It's up to you though.

 

[suprra_girl]

i'll go with your suggestion then as i already have the hose off so it's not really any extra work

 

[IJ.]

Better safe than sorry!

30 seconds with no Oil Pressure on a tight new motor will scuff up the bearings pretty badly.

 

[suprra_girl]

woot got 5psi so far hehe
cept my batteries keep going flat

 

[IJ.]

LMAO give it a break till the batteries are fully charged low V isn't good for the starter

 

[Piratetip]

Melting the insulation off the wires can be fun!

 

[jmanbball]

If you wanted to prime the engine without cranking it, couldn't you spin the oil pump up with a power drill before putting on the timing belt. It would be like priming a SBC by chucking the shaft of a screwdriver in a drill and spinning the oil pump through the distributor hole.

 

[suprra_girl]

now the other thing.... do i start it with coolant or just plain water?

 

[jmanbball]

No reason to start with straight water, so I'd use whatever mix you plan on using to start with.

 

[IJ.]

Coolant right away

Corrosion on bare metal starts in minutes so why give it a push start in the motor

 

[suprra_girl]

okie dokies i got a 4l pack so i figure i'd tip all that in & fill up the rest with water
actually wait, i'll do water first so that if i have a leak i don't waste my green stuff haha

 

[suprra_girl]

woot!! no leaks!!!
just finishing up topping up the tranny

 

[IJ.]

Green is bad

 

[CyFi6]

Coolant right away

Corrosion on bare metal starts in minutes so why give it a push start in the motor

I had read something somewhere about running strait water after a headgasket job to help it seal or something like that? Do you have any idea what im talking about or am i insane