I just rebuilt my engine, and I want to know if I should be paranoid of my oil pressure.

First off, I know that the stock gauge is crap, and I don't have the money to get a real gauge yet. I'm mostly wondering if this is "normal" for other 4Runner 3VZE drivers. Sometimes, the pressure gauge drops a tiny bit further than it is at the beginning of this video, but only when it's warm outside, and engine is at idle.

Thoughts?

[YOUTUBE]iaBr7fjDEg0[/YOUTUBE]

 

My gauge sits only a little higher than that.

If you're worried, mechanical gauges are cheap. I had one for my FIAT, just for testing. It plugged into the same hole the oil pressure light switch fit into. It probably cost $20 or $30.

 

What weight oil are you using?

 

10W/30 with no additives.

For my first 500 miles, I had 10W/30 with a Zinc additive, but have since (120 miles ago) changed the oil and did not re-add the Zinc additive.

During the first 500 miles, same pressure readings, BTW.

 

I use 5w/30 synthetic it sits at the middle of the gauge with regular driving... but when I first start it up its just over the first line.

 

Toyotas generally like 10w/30 so thats good that your using it. Those gauges are a very inaccurate and a general "visual" of oil pressure. Does the engine at idle seems to make alot of "chatter." Looking at that gauge the oil pressure is "ok." You said you rebuilt the engine? To what extent? Did change the oil pump with the rebuild. <-- Generally thats a rule of thumb is to always change an oil pump in rebuild. Plus in those vids the engine is "warmed up" the oil will thin out a bit upon warm-up and pressure will drop off a bit. If you really want to pursue this then get an oil pressure gauge and hook it up and see what the oil pressure is at idle and see if the gauge pressure changes randomly if at all. I believe the oil pressure for the 3.0 at idle is supose to be no less than 4.3 PSI and at 3000 rpm 36-75 psi. <---Engine must be hot

 

My friends gauge was reading just like yours after he rebuilt his engine. He went to napa and got a replacement sending unit for $40 and it reads alot higher now. First line at idle and the 2nd line at 2k

Id go to napa, or an auto part store of your choice, and get a sending unit.

 

I agree with what kiroshu said, 10W/30, factory gauge is inaccurate, oil thins after warm-up, get a mechanical gauge to diagnose if you're worried.

I 'm not sure you automatically need to replace the pump, though. The FSM has detailed procedures for checking the pump with a feeler gauge and precision straight-edge. I've checked two @ about 150k miles, and they were both perfect. Did you follow this procedure during the rebuild? How many miles on the engine before rebuild?

 

^Thats a good pratice to check the oil pumps clearnces but while rebuilding an engine and replaing all those parts and have it all apart and easy to get to its just best to replace the pump and I've always recommended that and many others will too... A fresh pump with a fresh engine so you know when it was done. Ofcourse being the pack rat i am i would replace the pump and keep the old one... check it and if its still good keep it as a back up ....wow i need to stop typing now

 

No way to be sure until you put a gauge on it.
Also as above...total rebuild? Was is different before
the rebuild? I see no problem using a used oil pump
if it specs out. It is checks out...then you know its good.
I bet alot of people just slap a new one on and never even
check the new one. I'd like you to check the oil sending unit too.

 

Hell, my needle sits LOWER than that, at idle, after she is warmed up, and has been that way for a year or 2. Thes stock guages are really just an idea of what the oil pressure is...I would only be concerned(on my rig of course) if the pressure guage didnt move when I gave her some throttle, or if it pegged all the way.

 

Mine sits at the first line at idle fully warmed on the hottest day, and usually around the 2nd line or just below it while driving.

 

I did a complete rebuild. I also did replace the oil pump.

Yes, in that video, the engine was warmed up and not under load (in Neutral.)

I do plan on getting a real gauge... I'll post my findings later.


I replaced the pump... I can't remember if it was OE or not... I bought a lot of parts. :-) I'll check sometime.


The needle was moving before the rebuild (based on RPM) but I didn't have the truck for more than 24 hours before I took it all apart. :-)


The main reason I'm wondering is because there is no Oil light, and therefore, all I have is this gauge, which is inaccurate. :-) So, I guess I'll have to get a real gauge.

 

From the million posts on "Is my Oil Pressure OK" I would say that it looks fine. Mine is a little lower than that and has always been like that and runs fine.

 

I realize this is an old thread, but I thought I'd post some notes...

I am currently in the middle of an engine rebuild (head replacement to oil pump).

My oil pressure read to the middle of the gauge which I consider the safe range. It will hover in the low range on idle (my truck idles in the 500 RPM range due to vacuum leaks and dodgy TPS). If it looks like it will stall, I can turn on the AC which brings the idle up to 800 rpm, but I digress....

For the low oil pressure, I added Mobil oil thickener. It did nothing, and in fact the problem has gotten worse after an outing to extreme environments.
For race engines, Mobile 1 oil additives will keep pressure higher, even under high heat so this was not the cause of the low pressure.
So, it's either the pressure sending unit or the oil pump. (I think). I believe it is the oil pump, because at cold tempatures, the guage operates as normal. When hot (normal operation range) and idle the pressure is far lower than I'd like.

The sending unit is the easiest part to replace (cheapest, too). So try that first.

As I am doing a rebuild, I am replacing the oil pump anyway, so I won't be able to tell you definitively that it was the pump or just the sender. But I'd change the pressure sending unit first.
Hope that helps someone.
-H

 

Here's a Toyota manual link for checking oil pressure:

http://www.ncttora.com/fsm/1990-1995...t/oilpress.pdf

 

IMHO... Forget about oil pressure in terms of psi... more important is oil flow, and viscosity .... You can have normal oil pressure, and still not have adequate flow, or viscosity.

 

i own a 93 V6 4runner and my guage does the same thing so i put a mechanical oil pressure guage on mine and at idle cold its 50-60psi warm it idles about 20psi cruise is around 42-psi if that helps

 

My 94 with the same engine and 10W-30W Synthetic runs about the same as yours on the L-H factory gauge. I think it is just fine. Like the others said if you are worried, hook up a manual gauge and check it.

 

Putting thicker oil in does not cure any problems, in fact it can exacerbate them if you have a pump problem. Go thinner if you're worried. My wife's 95 SR5 scares me all the time because as soon as it warms up the pressure drops off completely according to the gauge. First time I noticed it, I pulled into a shop and had the pressure checked. It was fine, completely within Toyota Specs. Changed out sender, worked a little better
for a day and then showed low P again. Just living with it so far with no problems.