Oil PSI problems (1 Viewer)

[motelcambodia]

HI From Cambodia,

I have a problem with my oil PSI, It will go to 0 or nothing at idle in gear some times but when driving it run at the H mark Im worred about it going to nothing at idle in gear water temp 200. air temp 95f or so.
Things I did to fix so far that done nothing ; I changed the oil to 20/w50 changed the filter not OEM toyota, new oil PSI sender. I do not get any noise like no oil PSI yet when it goes to 0. The motor seems to run fine lot power no bearings noise at start up.

Where can I look next? Could the Presser regulater be the problem? Does it have one? Oil Filter?
Why running at 60 mph its toped out at H and nothing at idle?
I seems to come and go ?
Need help before it blows up.

thanks
Brian

 

[Brian894X4]

In general, oil pressure is normally extremely low at idle. Idle in gear is the lowest rpm the engine usually runs, so the oil pressure is going to be the lowest at that point. Add humidity, high heat and the oil pressure will be even lower. All normal.

I don't have the spec in front of me, but normal oil pressure at idle can be as low as around 10 psi or sometimes even a few psi lower. Oil pressure idiot lights (which we don't have) are usually set to go off around 4 to 5 psi. While on the highway at highway rpms it will be a lot higher, something like 50-70 psi. 5-10 psi on a guage like ours is probably going to look pretty darn close to zero.

My guess is that your situation is a combination if a somewhat inaccurate gauge (very common with these factory garbage oil pressure gauges) and running at the bottom end of normal idle oil pressure due to the ambient condtions.

You're probably fine, but find the spec for both idle and highway and put a mechanical oil pressure gauge on it and have it tested just to be sure.

If pressure drops to the point of it not lubing the engine properly, it should start to get pretty noisey. I'm not sure about the 1FZ, but based on my experience with the 22RE, which uses a similiar timing chain/oil pump system, the upper end of the engine usually starves for oil first and the valve train and chain get pretty noisey. If it's all quiet, then it's "probably" fine. Since oil pressure is fine on the highway, bearing wear is probably not much of an issue either way.

Again, testing with mechanical gauge never hurts, though.

 

[cool breeze]

Pretty normal...i had the same problem intermittently when i first got the cruiser. Got a new oil pressure sending unit and got better, more accurate readings. Very easy to change, a one job

 

[Waggoner5]

It is not going to actually be 0 or things would get pretty noisy. I have checked many with a mechanical gauge and 20 psi hot at idle is not uncommon. I would replace the sender as cool breeze suggested and see how it changes.

 

[SeanAndHis80]

HI From Cambodia,

I have a problem with my oil PSI, It will go to 0 or nothing at idle in gear some times but when driving it run at the H mark Im worred about it going to nothing at idle in gear water temp 200. air temp 95f or so.
Things I did to fix so far that done nothing ; I changed the oil to 20/w50 changed the filter not OEM toyota, new oil PSI sender. I do not get any noise like no oil PSI yet when it goes to 0. The motor seems to run fine lot power no bearings noise at start up.

Where can I look next? Could the Presser regulater be the problem? Does it have one? Oil Filter?
Why running at 60 mph its toped out at H and nothing at idle?
I seems to come and go ?
Need help before it blows up.

thanks
Brian

Changing to 20/50 oil will have to opposite effect than what you think. Sure pushing 20/50 through a tube will show higher oil pressure than say 0/30 but... and this is the big one - that is only half of the equation. The ability to pick up that oil and pump it is the other half - which the thicker oil makes more difficult. I lighter oil will flow better. This means it will circulate better, get filtered more often and get cooled more often. Bearings work on hydrostatic pressure - more flow is better for them. Give the 20/50 back to the dinosaurs.

 

[joinerman]

Put a proper gauge in, you'll know for certain then.

 

[Tapage]

X2 in the aftermarket good quality gauge ( or mech one ) and let's figure that you should have at least 4.3 PSI @ idle and more than 36 PSI @ 2k rpm .. all at normal operative temp ..

 

[powderpig]

20/50 may actually bo OK for the area that this truck is in. EPA regulated oil thickness here in USA and that is why we got 10w-30. If you happen to look at some charts around the world, you can see, it is reccommended for outside temps like it may be in Cambodia.
Try not to be to Ethnocentric when making reccomedations.
Yes Oil Viscosities have been brought up and hashed out, try the search function.
I would do as some suggested and put a good oil pressure guage to the oil galley and see if you really have a problem.

 

[motelcambodia]

OK thanks guys
I had a new sender put on at toyota here in Cambodia and a new crankshaft seal checked the oil relif valve and they seem to thik its all ok too.
So I will go with that no noise runs good .

Done some hard core 4x4ing here flooded roads river crossing water over the hood . heading out tonight to (loas spelling?) the country north of cambodia 400 to 500 mile trip or more. also cut off the cats today I will see what happens now!!!!
Thanks
Brian

 

[powderpig]

I would still have a mechanical gauge hooked up to make sure that you have oil pressure. Or install a aftermarket electric one as in Post #6. Min Psi at idle is 7psi. As Gary posted, most will see 15-20 psi.
Good luck

 

[SeanAndHis80]

20/50 may actually bo OK for the area that this truck is in. EPA regulated oil thickness here in USA and that is why we got 10w-30. If you happen to look at some charts around the world, you can see, it is reccommended for outside temps like it may be in Cambodia.
Try not to be to Ethnocentric when making reccomedations.
Yes Oil Viscosities have been brought up and hashed out, try the search function.
I would do as some suggested and put a good oil pressure guage to the oil galley and see if you really have a problem.

Since I am the only one who mentioned the weight of the oil not helping the pressure - I will assume this was directed at me. I was not being Ethnocentric at all. I was simply stating that going to a higher viscosity oil to get better oil pressure does not work. Not just my opinion but an opinion gathered through a lot of reading on sites like Bob the oil guy and my own personal experience on the three cars I currently maintain and dozens in the past. I stand by my recommendation that if he is concerned with oil pressure - not to run 20/50. If in that heat range - that is all that is spec'd for the cruiser so be it but that is not how the OP made it sound.