1hz oil pressure....

[Sniperx]

Searched and found some info but I need something simple and specific.

I have a 1HZ turbo'd with OEM oil pressure gauge. Cold or hot, high RPM or low....it never really hits "the zone". When warm and high rpm, I get just to the beginning of the normal zone marking, when idle, center of the space below it. Hot or cold is pretty much the same.

This the gauge, sending unit, or something far more heinous?

I have a mechanical gauge setup I'm building for the rig (pressure, water temp, boost) but waiting for it all to arrive. Before you go saying get an EGT meter before a boost...I have one and find it fascinating to watch.

Also, only 140,000km on the rig.

 

[roscoFJ73]

There has been lengthy ,if not the lengthiest, discussions on diesel oil pressure.

1 the factory gauge and sender is only an indicator,when it varies dramatically you have a problem.

2 it is unreliable

3 the only way to be sure is to plug a mechanics pressure into the sender location and take a real reading in PSI as per FSM

4 most owners report that it hovers above the halfway mark at speed ,and at idle drops down to a quarter.

I dont know what you mean by the zone,both mine have a gauge with 3 marks spaced differently.
Are you looking at the wrong gauge?

A new or rebuilt 1HZ will attain 80 psi at 2000 rpm ,34 psi is the minimum,50-60 is a good average(for 140k).
At idle it is only around 6-7 with 4 psi the min.

 

[Sniperx]

Right, I knew all the PSI and mech info...read those..in fact you posted in some of them. Even watched a video. Hence, why I said I have gauges enroute.

Heres a picture:

The engine is obviously off btw. It is about halfway between the first line and the bottom during idle, little higher during cruise, and hit the bottom line of "the zone" when high rpm.

 

[roscoFJ73]

Right, I knew all the PSI and mech info...read those..in fact you posted in some of them. Even watched a video. Hence, why I said I have gauges enroute.

Heres a picture:

The engine is obviously off btw. It is about halfway between the first line and the bottom during idle, little higher during cruise, and hit the bottom line of "the zone" when high rpm.

Well its time for the mechanics pressure gauge.
The sender in the LH side of the block is interchangeable with about 30 Toyotas ,petrol and diesel,and cheap if you know where to look.

If the gauge is no good they usually sit down much lower than the lowest mark when the engine is off according to my wrecker.

An oil change can often push the gauge up a few mm.
My old 3F would tell me the oil needs changing when the gauge dropped.

 

[Ron R]

The indications I see on my 1HZ is two (when cold) or two/three needle (warm) widths below the first mark at idle and about one to one and a half needle above that same mark at RPM above 1500. Only when realy cold the needle will sit approx 3 widths above for a short time (2-3 km's).

Even when I get close to max RPM the indication will hardly change.

 

[Sniperx]

Sounds normal. I'm still installing my gauge cluster though.

 

[lelandEOD]

Figured I'd add on to this old thread rather than start a new one.

I have a freshly rebuilt 1HZ and I've noticed that it takes a long time to build any pressure from a dead-cold start and I'd like to know if this is normal or if it's indicative of something amiss. I'm giving myself heart palpitations watching that needle sit at 0 pounds for up to 4-5 seconds. Once pressure builds, it quickly climbs to 75/80'ish pounds until the engine warms up.

Kind of seems like the lubrication system is loosing its prime overnight. Thoughts?

 

[roscoFJ73]

Mine have always come up in 3-4 seconds including the 3F, it varies according to oil viscosity and ambient temps.
I was getting 80ish doing the described tests in the FSM when the engine was newly rebuilt with a few hundred klms done.
I think you are worrying over nothing.
If you shine a torch inside the rocker cover , you should see oil flowing around.

 

[lelandEOD]

Mine have always come up in 3-4 seconds including the 3F, it varies according to oil viscosity and ambient temps.
I was getting 80ish doing the described tests in the FSM when the engine was newly rebuilt with a few hundred klms done.
I think you are worrying over nothing.
If you shine a torch inside the rocker cover , you should see oil flowing around.

Thanks, Rosco. I'm not worried about the engine making good oil pressure; it's holding 15-17 pounds at idle when warm and is in the 40 pound range at cruising speed. I am (was) more concerned about the amount of time that it seems to be regularly making to build pressure from a cold start. I was starting to worry that I somehow installed something wrong or forgot an important component designed to retain the pumps' prime. If this is normal, I'll just have to get used to the motor running with no active lubrication for the first 4-5 seconds.

 

[roscoFJ73]

Ive pulled a few 1HZs apart, even after a 4-5 years they still have a film of engine oil coating the moving parts. The bores dry out a bit but I think the crank splashing around on the starter and then idling coats the pistons each time they come down.