No oil pressure after sitting
 

So at my last track day I broke my turbo manifold, and have had the car sitting for approximately a month since then. In the last week I finally got the manifold back from being repaired and ceramic coated and put the whole car back together only to find that my car has 0 oil pressure on startup. I've tried cranking with the coils unplugged, and fuel injector fuse pulled just to see if it would build pressure and got nothing.
I've pulled the filter off and cranked just for the hell of it and nothing is coming out of the block. I've tried putting a fitting and hose in an oil filter and using a shopvac to pull vacuum and get some oil flow, that also didn't work, but I did manage to get some oil in the hose, and after cranking some more there was still no pressure.

I know for sure that the motor is full of oil, but this issue has got me stumped, the car had oil pressure pulling onto the trailer coming home and pulling off of it, it sits for a month and magically has none. In the time the car was down the only thing I think could have affected it was that I drained the oil and relocated my oil cooler and shortened the lines, and did an oil change once the system was sealed back up, nothing too out of the ordinary.

If anyone has any ideas or suggestions I'd love to hear them before I pull the motor.

Use a transmission filling pump and back feed the oil system via the turbo oil supply hose. Pump the engine full of oil. Will be damn messy. It sounds like you have a completely dry oil pump that cannot create a vacuum.
See you tonight...
Rick

Any port in the engine will work, even the tiny plugs in the head galleys.
If you drain the sump first and leave the drain plug out you can tell when you've gotten fresh oil in the pan. When you see fresh oil coming out of drain plug via the oil pump install plug, fill, test.
If it's still 0 you're screwed...
Use to have to do this regularly on odd-fire GM V6s, "231". they were POS

What oil pump are you running? When you say it started without oil pressure, how long did it idle/run without oil pressure? I've seen cars take up to 5 seconds to get oil pressure after sitting for months.

I've had it running 3-5 times for no longer than 10-15 seconds and it never made pressure, I've cranked for probably 30 seconds a few times as well.

Oh and its a boundary engineering pump

10-15 seconds total, or each time? If total and you haven't let it idle for several continuous seconds, I'd crank it for say 7-8 seconds of idling, if no pressure, shut it down, throw away that oil pump, and put a stock mazda pump back on it that won't stick a relief valve.

Pull the plug from the oil pump by the alternator and pour a little oil down into it. Replace the plug and crank it over with the spark plugs out until oil flows out of the filter location. This is directly priming the pump gears.

Is there a certain amount of times i should try this? 5 tries so far and nothing

You put oil directly into the pump 5 times?

you put oil in here?

https://www.miataturbo.net/attachmen...mp-passage.jpg

Yes. Filled it, put the plug back in. Cranked car for 30s and got nothing. Repeated it doesn't seem that the pump is pushing any fluid out.

No idea on why but I'd bet the pressure relief is stuck open. I've seen that happen before. Fredb

it could be that the relief is stuck open. only way to know for sure is drop the pan i think.

I have never had to prime an oil pump like that to get one to work. If you did it 5 times and it's still not making pressure, stuck relief valve is my guess.

Oh well, thanks for the help guys, I guess I'll pull the motor and see what's going on.

You mean an OEM pump like boundary uses for their cores?

Well given it appears his boundary pump is malfunctioning, I wouldn't recommend replacing it with another boundary pump. I was recommending he throw it away, and use a stock (and not modified by anyone) OEM pump. His car, his choice. Maybe he has a ton of miles/use on the pump and it's just wore out? I dunno.

Or, perhaps your oil gauge is broken, given you a false reading? Last thing to try, disconnect your oil feed line, stick it in a bottle, and then crank it. You should see oil coming out even on the starter motor. Like this:

mods probably should just delete this post... :eggplant: