plugy1972
|
 posted on 12/5/12 at 12:03 AM |
|
|
oil pressure
Engine is a 2.0l zetec when i start it it goes to about 30-60 psi but the hotter it get and longer running after 5 mins the pressure goes to 0, the
dash light dosnt illuminate thought.
Have had new filter and oil any ideas.
|
|
|
|
|
cliftyhanger
|
| posted on 12/5/12 at 06:33 AM |
|
|
If the oil pressure goes to 0 then I would be inclined to check the oil pressure gauge/sender. I assume the oil light is on before you start the car,
and goes off when running 9obvious, but they go faulty too)
0 oil pressure should cause some odd noises PDQ....but a fair chance the worry gauge is playing up.
|
|
|
stevegough
|
 posted on 12/5/12 at 07:21 AM |
|
|
Don't want to worry you, but.....
I had a lot of oil pressure problems with my vauxhall redtop - showing pressure when cold, then dropping to near enough zero when warmed up. Turned
out to be firstly the oil pressure relief valve (in the pump body) first, (which meant the oil was not being pumped around the engine!!) then when I
fixed that, I ended up replacing the oil pump completely. Now its fine.
Don't automatically think its the pressure gauge - especially as it registers a pressure when cold - oil is thicker then, and can't be
bled out of tiny clearances / wear until it warms up.
Luego Locost C20XE.
Build start: October 6th 2008.
IVA passed Jan 28th 2011.
First drive Feb 10th 2011.
First show: Stoneleigh 1st/2nd May 2011.
'Used up' first engine may 3rd 2011!
Back on the road with 2nd engine may 24th
First PASA mad drive 26/7/11
Sold to Mike in Methyr Tydvil 19/03/14
|
|
|
big_wasa
|
| posted on 12/5/12 at 07:47 AM |
|
|
The standard low pressure light comes on at about 5psi. When over 100deg my oil pressure is around 10psi at tick over. Thats a rebuilt engine with new
beaqrings ect.
This looks to be inline with what most others are getting on a zetec. The oil is thinner than lots of other stuff @ 5w/30.
As long as your getting good pressure above tick over I wouldnt worry. As for your gauge, it could just be wrong.
|
|
|
snapper
|
| posted on 12/5/12 at 09:36 AM |
|
|
"As long as you get good pressure at tickover I would not worry"
I bloody would, you need 8 psi per 1000 rpm.
We run our engines hard and at high revs, oil pressure is all.
Check sump pickup for crap, just stripped an engine and found sump gasket sealant all over it, cleaned it out, pressures now good, 4 to 4.5 bar
stinking hot and pressure rises as expected with revs from idle
I get goof base pressure from idle which is constant till the oil gets hot then I get a slight drop which is recovered with revs
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
|
|
|
plugy1972
|
| posted on 12/5/12 at 10:59 AM |
|
|
The hotter it gets the worst the pressure.
When i rev it the oil pressure goes down the more revs and hotter it slowly reaches 0.
Took for a test drive down the lane couple hundred yards started to overheat temperature over 100 water not circulating properly, and oil pressure
dropped, but dash warning light didn't come on, but did make a very strange noise from somewhere in the engine bay twice like a screech when you
try to turn over the starter when the engine is running
|
|
|
britishtrident
|
| posted on 12/5/12 at 11:57 AM |
|
|
A change in Oil pressure is an engine health symptom.
High oil pressure is not an end in itself.
Actually an engine doesn't need oil pressure at all what is needed is copious oil flow into the bearing
It is a common misconception among non-engineers that the pressure from the oil pump keeps the bearing surfaces apart, metal to metal rubbing within
the bearing is prevented by the bearings internal oil pressure which is generated by by hydro-dynamic lubrication. This internal oil pressure is
many times higher than anything the oil pump can generate.
http://www.marinediesels.info/2_stroke_engine_parts/Other_info/hydrodynamic_lubrication.htm
Now given all that an indicated 0 psi when hot this is a symptom that should be looked at, most of the possible causes have already been
mentioned.
(1) Stuck relief valve
(2) Worn oil pump.
(3) Normal wear on the bearings.
(4) Oil temp v viscosity
I suspect it is just down to normal wear on the bearings and oil pump, I suspect dropping the sump fitting a new set of big end bearings,
clean the relief valve and oil pump suction filter and change the oil pump will bring a big increase.
However before doing that if the engine is running on 5w/30 try 5w/40 or even 5w/50 and measure the oil temperature if the oil temp is
high consider fitting a cooler and thermostat.
But don't be tempted to put a very high viscosity oil or add an oil thickening additive into the sump.
[Edited on 12/5/12 by britishtrident]
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
