this right here, says the LPOP is bad, or the suction pipe is broken, fallen down?
Put on a new LPOP first, and see if it starts.

Leaving that plug out, should have pumped the entire crankcase empty of oil, fast.

 

An empty HPOP reservoir will not allow the HPOP to build pressure, and thus the injectors won't fire even if the HPOP is totally fine.

We know that based on what you posted that you have:

1. Enough oil in the crankcase.
2. No low-pressure oil pump pressure in the HPOP reservoir, you took the reservoir plug out and no oil shot out.
3. A no-start condition even when you refilled the HPOP reservoir, plus the crankcase oil level was high after filling the HPOP reservoir multiple times.

The lack of the engine starting even with the HPOP reservoir being refilled either means there is a massive leak in the HPOP reservoir, its gasket with the HPOP, or front cover where the oil drains back very quickly to the crankcase after the HPOP reservoir is refilled, or you have other starting issues in addition to the lack of LPOP pressure. I would first look for a massive leak as a leak big enough to drain a filled HPOP reservoir before the engine can fire may be large enough to lead to zero LPOP pressure as the oil would just leak back to the crankcase and not build pressure.

Here is a thought, fill the HPOP reservoir and watch the oil level over a few minutes. If you top it up and the level drops quickly, that would confirm a massive leak as above. If not, then you will want to check an actual low oil pressure value, you would need a mechanical gauge or an actual electronic sender and external electrical gauge to do this as the engine doesn't have an actual low oil pressure sensor.

 

Sounds like a lpop to me. With plug off top of hpop reservoir oil should be spraying everywhere out of the hole. I accidentally left mine out and fired it up one time and had a hell of a mess in no time. Sprayed oil all the way up on the open hood. lol

 

Also just to add the "anti drain back valve" thst many call it is not actually a anti drain back. It is a short circuit valve used for filling reservoir during starting. That valve can 100% not cause the reservoir to drain back empty. It's physically impossible the way it's designed. It's just a common misconception people say. So just forget you ever heard that that could be the problem.

 

How long should i crank motor is hpoip reservoir fill cap removed to see if oil flows out?

 

Added qt to hpop reservoir last night and again this morning. Possible for hpop oil to drain into oil pan?

 

Seconds. Maybe even one.

Also, unless it was catastrophic LPOP failure, you would have seen some signs of it starting to get tired. Across the board longer crank before start, an occasional, subtle hiccup or rough patch that seemed out of the blue or random, that type of thing. Also, if the longer start only happened when the engine was cold (not necessarily winter cold, but after sitting overnight). If it came on all of a sudden, I would lean towards what @JohninOkieland mentioned about the pickup coming undone.

 

If you are adding all sorts of oil and it isn't winding up on the ground, then it will eventually make its way back to the oil pan, especially if you cranked or ran it. When I dealt with a played out ol' LPOP, I would have to be mindful of the level in the oil pan.

I guess it is possible for oil to weep back to pan thru the worn out lobes of the LPOP pump? It would seem to me that that pump would have to be really eroded to make that happen.

 

Yes if the reservoir gasket has failed the oil can drain back to the pan. I suppose if it was bad enough the reservoir may not fill at all. How long does the oil last in the reservoir when you fill it? Don't bother refilling it to check. The gasket is obviously bad if you've filled it and without cranking the engine the reservoir empties itself. Doesn't matter if it takes 5 minuets or 5 months the reservoir should always hold oil.

 

So do you think lpop is bad or failed gasket is the issue? If lpop is working but hpop reservoir gasket failed would that cause a no start being pressure is not building due to failed gasket? Or do i have 2 issues, failed gasket and lpop?
Thanks.

 

Where is hpop pickup tube loaction?

 

If reservoir is draining just sitting I would suspect a lower reservoir gasket failure or front seal on hpop failed leaking the oil through the hpop.

There isn't a hpop pickup tube.

 

Failed lower reservoir gasket would cause a no start due to lack of oil pressure?

 

If the hpop reservoir is empty it's not going to start.

 

Years ago I ran into a similar issue where the lpop had worn into the timing cover causing a no start but I don’t recall the hpop reservoir draining without cranking. I would start at the top and work my way down. The last thing I would want to do is pull engine to check pickup tube.