Where's the sender?
A definitive answer of what oil is in there will help a lot.
New or reused oil pump? What size?

A lot of pressure tales will be based on the tolerances the bearings had upon final assembly. Was it a stock rebuild? OEM shortblock? Oversize bearings anywhere?

 

Ah, forgot to mention that, sender is right on top of the oil pump, underneath the alternator, where the stock one was. I relocated the stock one to the hole in the back passenger side area. Completely stock rebuild, nothing should have been oversized unless I was not informed of it.

 

@ 600rpm's, oil pressure should be 14psi for 7, 9, 10, 11, and 12mm pumps.

I would inquire the shop about why the pressure is low.

 

I was hoping you would say the sender is somewhere stupid and causing issues.
You can look at the receipt for part numbers to see if they ran oversize bearings, new pump, or other machine work that might give you a lead.

I bet there is a spec in the service manual for oil pressure in the "on car diagnostic" section. May be good ammo to take with you when you ask the questions.

Maybe try the concerned customer role and tell them you want to nip it before the motor spins dry.

 

Ask for oil clearances for each bearing too, any good engine builder should have recorded them

 

In this case, I'm almost 100% positive these guys did not do that. It's a hole in the wall shop where 90% of their mechanics barely understand English. (Another long story why I even went there the 2nd time around....)

From the way it sounds, I'm pretty much screwed if I wanted those guys to fix it properly.

Lets assume the oil pump is fine, and they reused a pickup that came from a motor that previously spun all its bearings, I should be able to argue that case then?

 

If that's the case, you probably should have changed the oil at least twice in the last 1200 break in miles. If I were you, I would change it asap with a good dino oil and a high relief pressure filter and see what happens.

If they slapped it back together with unknown bearings and rings, the same rods without even measuring, without hot tanking the block, you have all kinds of bearing in there from last time.

 

Which electrical gauge did you use?


10psi at idle isn't going to kill the motor, just don't dog the motor when its warmed up until you can get it checked. It could be a few things, including high bearing clearance (like previously mentioned), a piece of trash holding the oil pump relief valve open, or an air leak at the oil pickup tube. Sounds like you may be in a bind if communicating with the shop is a problem. My car idles around 15 when warmed up and while I'd rather it be a little higher, some vehicles have almost half this spec at idle and are perfectly fine. You don't have high loads at idle speeds, so the engine doesn't need tons of oil. If it were my car, I would make sure the oil pump relief valve is clean and working properly (its a bit of a pita being under the timing belt covers and the spring is pretty stiff) and the pickup tube wasn't cracked and had the proper o ring at the top (also sucks because the oil pan has to be removed). Even if its not cracked, having too thin of an o ring at the top (or none) can cause a loss of pressure. You can add a shim under the oil pump relief spring to bring idle pressure up if everything else is ok and you're feeling froggy, but if the pump and pickup tube are ok, the bearing tolerances are likely to blame. :/ There could be high wear on them (if not changed) or even one or two with very large clearance.

 

First I'd like to thank all you guys for all the suggestions.

I'm currently using a prosport gauge. Yea I know they are hit or miss, which is why I wanted to verify with a mechanical one I picked up at Harbor Freight.

For now, I changed the oil with some Shell T6 5w-40. Nothing suspicious looking in the old oil. Did the same warmup loop I did before I took that previous vid, and from the electrical gauge, cold start was 90 psi and warm idle was 20ish. Hopefully it will stay more consistent as I add more miles to it.

A pickup tube is probably next on my list just to give myself piece of mind.