question Low Zetor 6718 engine oil pressure

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

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?

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

Zealous said:

1 bar pressure @ 2000 rpm hot

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That is much to less.

Zealous said:

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

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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.

Zealous said:

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

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Zealous said:

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

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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?

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