So on my new forged motor, the brand new boundary oil pump refuses to prime. We’ve probably cranked it over for 2 minutes at this point, and I don’t want to keep going and toast a bearing/ruin the cams. Nothing came out of the oil filter location so far. Not a drop. Brand new pickup gasket, clean surfaces, o-ring, everything that was supposed to be done was done.

We were going to remove the 1/8” NPT port on the top but it is so tight we can’t get it off. Next step is to remove the oil filter warmer/cooler thing to see if we can pour oil into the pump that direction, but I’m doubtful it’ll work. Boundary oil pumps should be greased up from boundary themselves from what I’ve read but it still doesn’t work. Any tips or ideas about pulling a vacuum (where to connect it, what to use to draw a vacuum, etc)? I really don’t want to remove the engine to **** with the relief valve. **** like this gets me so demoralized it makes me want to sell the pos. Anyone want a ‘99 with a 2560r and forged engine/built head? /j

 

You won't hurt it on the starter.

Here's what I'd do.

Kill fuel pump, unplug ignition coils, pull spark plugs, connect a running car to your miata's battery to keep the voltage at 15.0V all the time.

Let it charge for 10-15 minutes.

Then get a stopwatch and hit the starter for 1 minute non-stop. If it doesn't have oil flow/pressure after that, something is wrong.

Go from there.

 

I had a similar problem, sticking relief valve after a refresh. Took the plug out, primed through the port, put the plug back, and away we go! Should have polished the port, but that meant too much work/delay, so crossed fingers and it never gave another moment's trouble.

 

The relief valve port to reduce potential for sticking the plunger?

 

Unless you've built as many BPs as Boundary has built oil pumps, I wouldn't blame the pump first. He's cranking this pumps out in huge numbers, and while mistakes happen, it's far more likely he's ironed out assembly issues than you've perfected building BPs.

IIRC, he offered coated relief pistons and/or polished bores at one point, however it wasn't worth the extra cost since it still could get stuck with debris.

If you still can't get oil pressure with a strong battery and removing the plugs, letting it idle isn't out of the question to really get some RPMs pumping. If the relief valve is simply stuck from sitting too long, extra RPM will hopefully generate enough oil pressure to unstick it. I've had reputable BMW engine builders (they're notorious for generating very little OP at cranking RPM) suggest running the engine at idle for up to 45-60 seconds to prime.

 

I’ll try this either today or Friday. Thanks for the idea of using another cars battery, we already have everything removed and disconnected like you suggest. Doing this won’t be harmful to the starter system will it? 1 minute straight seems like it might generate some good heat.

We were going to attempt that but the port is extremely tight. Couldn’t remove it with our Allen keys and we don’t have metric Allen key/bits for a ratchet wrench. We were going to remove the oil cooler/heater thing to pour oil into it there so it’ll hopefully feed into the pump.

This will probably be a last ditch effort before removing the oil pan. I’ve got a spare crank too, so if it doesn’t build pressure and ruins the bearings/crank surface, it wouldn’t hold up the build too long. Still though that makes me nervous as hell.

Boundary themselves pretty much said the same thing: “Its likely you need to actually start to the car to build oil pressure. Gerotor pumps are terrible low-speed oil pumps, they only work reliably at 600-700 RPM or greater. If that doesn't work, I would try over filling the car and racking the back of it up to see if there is some sort of leak with the pickup tube system”

 

Sub'd. Glad to have read this before finishing/dropping in my built motor. Thanks for the useful information guys.

Will be waiting for the conclusion.

 

Yeah, should have made it clear mine was not a Boundary pump, was offering it as way to prime not a criticism. And yes, I believe these can be tight.

 

Heat build up will be cumulative, but the ability to prime will be tied to how long and how fast you hold the starter spinning. So 15 seconds, pause, 15 seconds, pause, isn't nearly as good as 30s without letting up.

I've spun my car over for 2 minutes on the starter before. With no plugs it's easier on the starter since there's no compression.

If it was assembled with assembly lube, I don't think running it for 10 seconds no oil would hurt anything. But I've never had to do that.

When I had two turbo's that needed oil pressure, it took 45 seconds to get oil pressure, that's the worst I've seen.

 

I took your advice and used another car’s battery so it wouldn’t drain my battery. It ended up taking about 40-45 seconds of cranking until I saw pressure. My issue was definitely doing it in short bursts. That probably let the oil flow right back out. Huge thanks to you.

 

I’d recommend doing what patsmx5 suggested in his first response, but more specifically cranking over in bursts doesn’t do anything. It’ll need to crank over until oil pressure builds. Stopping will put you back where you started.

 

Glad it worked! Now the fun begins!

 

And here I am just a tiny bit smarter than yesterday. Thanks guys

 

FWIW i had the same issue with my build when first trying to get it started, even with 1-2 minute cranking intervals. Started it up and it saw pressure within 5-10 seconds. that was a few years ago lol.

 

Interesting.. I am feeding oil to two turbos and I see oil pressure instantly.
I have 2 oil pressure senders; one on the sandwich plate for overall engine pressure, and one on the oil manifold feeding the turbos just to make sure.

 

@Godless Commie .... This thread is about initial priming on a new build... not normal starting.

EDIT: Your service to your fellow countrymen was / is impressive indeed.

 

I'm a few days away from starting up a fresh rebuild.
This is a good heads up for me, I put a boundary pump on my new engine.

But, I did pour a little oil into the pump before I bolted on the oil pan.. Saw Al do it on his A+ racing video

 

Unrelated, but that engine looks stunning.

 

Man, I love threads like this. Someone comes in, thoroughly explains the problem and questions, gets immediate and helpful advice, the advice works and OP returns and reports.

And now Jacob can enjoy the Tecnas he won instead of parting his car out

Miataturbo.net FTMFW

 

Now I need time to install them, hopefully this weekend