No oil pressure at start up 12HT

[LenaW]

When I cold start my 60 with a 12HT engine it will take maybe 5-8 seconds before it gains any oil pressure. After that the pressure is normal.
I've changed oil and oil filter (Toyota) 1000km ago.

It has a ticking noise the first 20 seconds after a cold start. If it were fitted with hydraulic valve lifters I've definitely guessed that. But as you know that's not the case. Is this normal on a direct injected diesel?

Also then it fires up it emidietly drops to maybe 400rpm in a 1/10 second then return to normal 800rpm.

Any suggestions? My biggest concern is the oil pressure.

 

[Tapage]

are you measure your oil pressure by a gauge .? it's mechanical .. ?

 

[LenaW]

are you measure your oil pressure by a gauge .? it's mechanical .. ?

I'm normally measuring oil pressure with a electric gouge but I've tried connecting a mechanical with the same results.

 

[roscoFJ73]

I'm normally measuring oil pressure with a electric gouge but I've tried connecting a mechanical with the same results.

What oil are you using and what sort of PSI readings are you getting?

 

[LenaW]

What oil are you using and what sort of PSI readings are you getting?

Cold: Idle Approx 3kg 3000rpm 6kg
Hot: Idle 1,0kg 3000rpm 3,5-4kg.

I think minimum is 0,3kg at idle and 2,5kg at 3000rpm.

That seems ok. Doesn't it?

I'm Using 20w50 oil. Before last oil change I used 15/40 with just a little lower readings.

Maybe I will try changing the oil+filter.

A year ago in my old 2H engine I had the same problem. It was a bad (cheap brand=never again) oil filter which caused it. But I doubt that's the problem now.

It hearts my soul every cold startup with no pressure. And maybe my bearings as well... A few seconds later the gouge flies up to good readings and me and my car feels much more relaxed.

 

[Tapage]

4.3 PSI it's by FSM the minimun recomended ( that if you ask me a bit lower .. )

In my cacse are around 20 PSI @ idle @ normal operative temp ..

 

[LenaW]

4.3 PSI it's by FSM the minimun recomended ( that if you ask me a bit lower .. )

In my cacse are around 20 PSI @ idle @ normal operative temp ..

Thats seems right. I downloaded the Toyota Repair manual for 2H and 12H-T and it says .3 kg which equals 43psi minimum at hot idle.

When I've driven for hours at 100-120km/h (62-74mph) i measure 1kg (14psi). Thats the lowest I'll ever get, even how hard I try.

If I drive a little more normal downtown or just 90kmh/h i will have about 1,5kg (21psi) after a long day.

 

[roscoFJ73]

Thats seems right. I downloaded the Toyota Repair manual for 2H and 12H-T and it says .3 kg which equals 43psi minimum at hot idle.

When I've driven for hours at 100-120km/h (62-74mph) i measure 1kg (14psi). Thats the lowest I'll ever get, even how hard I try.

If I drive a little more normal downtown or just 90kmh/h i will have about 1,5kg (21psi) after a long day.

If the 14psi and 21 psi is at a hot idle, that is good.
The all important psi figures are at high rpm around 2500
Its also important the engine can hold the same psi at for 2 mins

 

[LenaW]

If the 14psi and 21 psi is at a hot idle, that is good.
The all important psi figures are at high rpm around 2500
Its also important the engine can hold the same psi at for 2 mins

Yes, that's at idle and it can hold the same pressure.

Any ideas why I don't have any oilpressure the first seconds at cold startup?

 

[Tapage]

Yes, that's at idle and it can hold the same pressure.

Any ideas why I don't have any oilpressure the first seconds at cold startup?

I have a mech gauge in my 2H ( VDO ) and it takes a bit to raise the oil press .. maybe 4 segs or so .. ( wondering about it never measure never worry to much about it )

thought it's the time that the oil press take to reach the oil gauge at top of my dash ..

 

[roscoFJ73]

Yes, that's at idle and it can hold the same pressure.

Any ideas why I don't have any oilpressure the first seconds at cold startup?

No engine has instant oil pressure and 5 seconds isnt bad anyway. The crank is bathing in oil and the piston rings trap some oil overnight.
Its not as if it is starting completely dry.
A lot of the paranoia about engines getting the most wear when starting cold is driven by companies selling magic potions

Replacing the oil pump might help get pressure quicker

 

[LenaW]

Ok, nothing to worry about then.