Low 6718 engine oil pressure

[Zealous]

Hi all,

I have a 6718 with low engine oil pressure (2 bar cold 1 bar when hot). has been like this for years, (Ain't broken don't fix, stich in time saves dime ?).
I've renewed shell bearings, to no avail. I suspect a faulty oil pump or maybe pressure valve?
I wonder if anyone could shed some light on this niggle, before I invest additional time & fund's in my Quest to save another relic of it's time.
Regards

 

[Joachim]

Hello John,

at what upm do you have this pressure? full throttle?
It should have min. 0.6 bar at low upm like 600 upm and a max from 1600 upm and 5-6 bar

Do you have checked all the points I marked?


- Oil pump can be, but should not the first part to control in my opinion
- Oil pressure valve can be, simply unmount it and let it test for right pressure or renew it
- also check part (6), the pipe can also be damaged so oil can drain from

How do you messure the oil pressure? What do you use for?

 

[Zealous]

Hi Joachim,
Thank you for your response.
Your written English is fine.

1 bar pressure @ 2000 rpm hot, 2.2 bar max pressure on start up when cold for 1/2 hour to an hour at any rpm 500 rpm +.
can drop to 0 bar pressure @ 60 degrees water temp and rpm @ 1500.
there is an oil pressure gauge fixed to dash panel as standard.
I shall investigate your highlighted points when time allows.
I really hope to resolve this niggle.

Regards
John

 

[Joachim]

1 bar pressure @ 2000 rpm hot

That is much to less.

can drop to 0 bar pressure @ 60 degrees water temp and rpm @ 1500.

That will be horrible bad for your motor if the pressure is correct. If that will be realy 0 bar, that kills your motor in short time. I cant believe this at this moment.

2.2 bar max pressure on start up when cold for 1/2 hour to an hour at any rpm 500 rpm +

there is an oil pressure gauge fixed to dash panel as standard.

Control it with a oil pressure messure gauge directly screw in at the motorblock reight side. So you can see if your dashboard gauge is a bad lyer or not and so your pressure messure correct or not.

What oil you use for motor? It should be a SAE 10W-30 API CB/CC diesel motor oil or if not possible a SAE 15W-40 API CD/CE/CF and no longer inside the motor like 300 hours.
Are the push rods really all OK? None crooked, cunning or one of the head loosers?

 

[Zealous]

thanks for vice-ad, I gotta make more time to cheque & resolve, ees a good reliable czech mate.