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Nitro_Alltrac
03-17-2015, 03:47 PM
I'm a little concerned that my oil pump might be starting to go.

When cold, the gauge is showning about 50 psi at idle. Once it warms up it's dropping as low as 14 or 15 psi at idle. At 3000 rpm warm, it's showing about 40 psi or so.

I'm pretty sure that it used ot run about 50 psi at 3000 rpm all the time. I'm due for an oil change so I suppose that I could have some oil breakdown.

The BGB shows that the allowable limit at idle when warm is 4.3 psi and that the range at 3000 rpm warm is 36 psi to 73 psi or so. I'm in those ranges but I am concerned that the pump could be going. The engine has about 130K or so on it and runs fine. I have few oil leaks that I need to track down and fix but nothing major.

It probably OK but I don't want to be heading out to somewhere like the Dragon and have the damn pump go.

What do you guys think?

alltracman78
03-17-2015, 11:14 PM
Toyota oil pumps don't usually just break. If they do there's a specific reason. No oil, bad installation, ect.

Has the temp warmed up for you? warmer temps mean lower pressure.

Rod/crank bearings wearing out? If they let too much oil by it will lower pressure.

Maybe your gauge is wrong?

I wouldn't be too concerned about it; but if you're uncomfortable with it you can always change it.
But

Nitro_Alltrac
03-18-2015, 02:30 AM
Thanks Jeremy. I didn't really think Toyota oil pumps were prone to failure but I saw some posts on a couple sites the other night that had me a little worried.

The engine is a JDM replacement that a OP had put in at about 161K. I found the Japanese receipt where the engine had been pulled prior to shipping and I had it translated at work. The engine only had a little over 19K miles on it when it went in. The car is showing 281K now so I figure the engine has 130-140K on it. Not sure about the bearings. The car still feels like it make power like it always has and I'm not getting any weird noises.

I got an Autometer electric gauge that was in the car when I got it. The sender could be going bad. I've got an extra one that I may swap in to see if that makes a difference. I've got to get the oil changed. I'm over due and I've let it go this time, something I've never done with this car. Been a ton of other things to get sorted in the past few months and then the shitty weather. I'll get it changed in the next week and see what the pressures look like then.

Luni
03-18-2015, 04:09 AM
The idiot light comes on at like 3 or 4 psi. Anything over that is considered normal depending on engine operation.

I wouldnt concern myself with it TOO much.

Hipster Lawrence
03-18-2015, 11:26 AM
Just want to throw this out there. Oil pumps provide flow, not pressure. Pressure comes from resistance to flow. So if you ever have a pressure issue look towards the bottom end bearings for excessive clearance.

That being said I think your oil pressure is just fine. As a general rule of thumb 1 psi per rpm is an acceptable amount of oil pressure.

donteatbugs
03-18-2015, 12:44 PM
You can try a slightly thicker oil too since its getting warmer. This will give a higher restriction and keep your pressure up maybe.

andy
03-18-2015, 01:14 PM
1psi per rpm, sooooooo
3000 rpm = 3000 psi
IM FUCKED lol

I think you meant 1 psi per 100RPM
or 3000 rpm = 30psi

andy
03-18-2015, 01:16 PM
On anther note, I hade the oil pressure drop in my truck due to a clogged pickup. A lot of the fipg had got brittle and broke off into the pan.

Also on my 2rz it reads like 12 psi at idle when warm. I thought it was alarming but its been fine for 3 months now.

Nitro_Alltrac
03-18-2015, 10:25 PM
Thanks for the input guys. I feel better about it now. I'll get the oil changed, hopefully over the weekend and see what it looks like with the new oil.

Hipster Lawrence
03-18-2015, 11:14 PM
1psi per rpm, sooooooo
3000 rpm = 3000 psi
IM FUCKED lol

I think you meant 1 psi per 100RPM
or 3000 rpm = 30psi

Oh yeah, that's what I meant.

Fucking engineers always showing off their math skills.

klapa
03-19-2015, 12:31 AM
The idiot light comes on at like 3 or 4 psi. Anything over that is considered normal depending on engine operation.

I wouldnt concern myself with it TOO much.

I would generally agree - though not knowing much specifics about a 3SGTE engine - if the tap point for the OP gauge is at the upper valve galley or the equivalent for a 3SGTE - then anything above ~5-10 PSI should be good enough to indicate bearing health.

Though if it has changed significantly from past readings - perhaps that would be a concern to find out why.