968CS_HKG

Is oil pressure indicate a sign for an engine rebuild? My 968CS is running between 1.8 - 2.0bar at idle when oil temperature at 90 - 95C and 4.0 - 4.5bar at acceleration. According to the manual, the engine should be running at 2.5bar at idle. Does it mean it is time to look at freshen it up? At the moment it has 93,000miles on the clock.

Deano968

I'm pretty sure better mechanical minds than me will answer your question. but FWIW, mine is about the same and always has been - had it from 30,000 miles. I expect that the readings are fairly normal.

I've also heard of the gauge pick-up becoming faulty to though in that case it just read high all the time.

968CS_HKG

OK, thanks mate!

odurandina

under acceleration, (just short of 5) to 5 bars is probably about ideal. under normal throttle, 4 to 4 and a half bars is fine. what you have is still ok, but normal engine wear might be telling you it's time to switch to a thicker oil (something every car's engine eventually requires). i would suggest running slightly thicker 15w50 like Amsoil.... and your oil pressure will come up a little.


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968CS_HKG

At the moment I am using 15W50, when going full chat, it will be showing a little short of 5bar (may be 4.6-7bar) on the gauge and 2 bar at idle or around 1.8bar when it goes really warmed up at 30-33C ambient heat. I am worry about the pressure when idling... it seems low when compare to the workshop manual standard.

tamathumper

That does seem very low. I'm at about 2.5 during hot idle. First of all make sure you're topped up on oil, as pressure will drop if you're low. You can get the oil pressure up with a thicker oil, but you'll have to address the real issue sooner or later - rod bearings, oil pump, cracked pickup tube,...?

968CS_HKG

I better get that checked out.

RajDatta

+1. Check for basics. If the oil pickup tube is cracked, you might get some variocam/tensioner noise from air in the oil pressure.
Raj

Cloud9...68

Mine behaved exactly like yours - hot idle was noticeably below 2.0. For this reason and a host of others, I pulled the engine and completely rebuilt it. I will be very interested to see if the hot idle oil pressure comes back into the accepted normal range, or will it stay low, in which case I'll have to conclude it's a issue with the gauge.

ernie9468

Mine with temp at the quarter mark-idling at 950 RPM showing 3 3/4 bar, under accelaration it goes rigth up to 5 bar -so at 1.8-2.0 bar it's kind of low.But like mention it could be a faulty gauge.Btw what density of oil are you running?(PLEASE PEOPLES DON'T START ANOTHER OIL THREAD)

Cloud9...68

Most recently, I'd been running 10W40, so maybe that was part of the reason for the low readings.

JET951

That will do it ,15w-50 or preferably 20w-50 , as it says so in the owners manual( that came with the car) oil viscosity chart in the shaded look at me section regarding multigrade oils , from minus 10 deg cel to unlimited high temp( sounds like TX to me ) = 15W - 50 or 20w-50 .

10w-40 = low oil pressure & lower oil film strength ( if both oils have the same ZDDP ) usually the 10w-40 will be lower on ZDDP

Cloud9...68

You make some good points. I was using 15W50 Mobil 1 when I first got the car six and a half years ago, but then I read somewhere that a lighter weight synthetic oil would provide the same protection at high temperatures as a dyno oil with a higher weight rating, so I started using 10W40 (Redline, and later Shell Rotella). I don't remember whether there was a change in my oil pressure gauge when I switched to the lighter weight oil. I'm going to go back to 15W50 when I'm done with my build.

968CS_HKG

I am running 10W50 in my CS, should I try using 10W60 instead?

ernie9468

Depending how cold it is in your part of the wood,why don't you give 20w50 a try.Btw there could be a difference in your oil pressure depending on which brand your using.(But once again don't want to start another oil thread).Personally I'm using Valvoline VR1 with ample ZDDP to protect a 968 motor without issues.