low oil pressure

[epic]

Hi,

Just wondering if anyone here has had the same thing as me or has any idea of known common causes but...

my 96 clio 16v has been showing low oil pressure for a while now, the pressure does go up and down with the revs but not as fast as before, low pressure oil the warning light flickers on and off very rarely when coming to a stop and the engine is ticking quite alot, like a tappets ticking sound.

I took it to two garages the first said that they think it ran two low on oil at one point or something and after a lengthy look at the car said they think it needs a engine rebuild, they also said the oil pump looks like it was changed at some point or messed with, the second guy (who didnt have as close as look at the first, just listened for 2 mins) said that it sounds like a dead tappet and that oil pump hardly ever go and that the low oil pressure might be because of a broken oil valve.

Anyway, has anyone had this problem or have any suggestions what is it? i obviously dont want a rebuild if not needed, but don’t want to cash out for something which isn’t the cause..

Thanks allot, regards Adam

 

[Infinicar]

Adam,

Have you had it measured on a proper mechanical oil guage? The sender/guage combination ISNT the most accurate/reliable.....

Paul

 

[BenR]

Does the engine still reach normal peak oil pressures at max rpm of about 3-4bar?

 

[JAY172]

as above whats your oil gauge read at:-

1,idle=

2,3000rpm=

3,max revs flat out=

 

[epic]

im pretty sure it was measured on a mechanical oil guage when the garage checked it out.

im not 100% sure about the levels, i will have to check tomorrow, but i know its not what it was a few months ago

 

[BenR]

we need pressures not levels to try and see if its your bearings or the pump itself.

 

[Scribbler]

Sorry to interupt but this has me thinking what is the correct oil pressure for a valver?

Mine shoots up to the limit over 6 bar when you turn the key but after 5 minutes of steady driving it goes to under 3 bar and about 2.5 bar at idle. Mine also has very noisey tappets when cold start. But if the outside temerature is hot (20deg+) it isnt noisey also the tappet noise goes after a few minutes whewn the oil is up to temp. I suppose this is all normal for an 80k valver but would be interesting to know what the optimum oil pressure is>?

 

[BenR]

Thats all because of oil viscosity change with temp. Colder oil is thicker, hotter is thiner.

Your tappets will tap when left for a while or cold, and your pressure will be higher when cold because the oil is thicker.

At the measured operating temp of 80C, the correct running pressure is:

idle = 1 bar

3500rpm = 3bar

 

[Scribbler]

So would you be conserned running 10w40 delphi semi-synthetic fresh serviced about 1 month ago should hit the max oil pressure mark when you turn the key, it takes a few minutes to drop to half way!

 

[BenR]

nope.......almost all do that if the pump and bearings are in good nick.

 

[Scribbler]

cool

 

[peterh2]

Thats a bit worrying for me, when I start it it goes to about 3 bar and stays there till it gets warmed up. When its at 80 degrees at idle the pressure is not showing anything on the gague, when im flat out at 7k rpm its only at about 3 bar. Only get about 1.5bar at 3,500 rpm. This mean I may have a problem? It does seem to run fine however, nice and smooth.

 

[BenR]

The gauges arent the most accurate so dont rely on them too much...if things go pear shaped the oil warning light will come on, then you worry.

What oil are you using and the viscosty ratings really affect temp related pressure.

 

[epic]

thanks for the replies so far
ok this looks bad,

idle .2 bar(hardly anything)

3000rpm 1 bar

7000rpm 5 bar

what do you recon?

thanks, cries

 

[BenR]

This is at normal running temp right?

 

[JAY172]

have you confirmed these readings with a manual plug in pressure gauge? how old is your oil and is it a decent quality oil?

 

[epic]

BenR, no its not it was with a cold engine, ill get running temp oil pres levels tomo, and the levels were only read from the dash gauge. the oil is new and more than good enough quality.

 

[Ben H]

My pressure gauge never goes above 1bar, even when the engine is stone cold! It rapidly drops to the bottom of the dial and doesnt really move as the revs change.

Im putting it down to a faulty sender, as if I relied on the gauge surely the engine would have died ages ago?!

Renault wanted £65 for a new oil pressure sensor, so Ive given it a miss for the time being!

 

[BenR]

From cold thats bad.....

Check with an external pressure checker and if its still close, id say its the pump, not the rings.

 

[epic]

do you think i should not drive it?

 

[epic]

also the pump his hard to change isnt it? cos of all the stuff in the way?

 

[BenR]

Its a little hard to change yes.

You should be fine driving it unless the oil warning light comes on.