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Hayo (Hayo328)
New member
Username: Hayo328

Post Number: 15
Registered: 7-2003
Posted on Thursday, August 21, 2003 - 1:58 pm:   

Hi Paul

My 328 shows 3 - 3,5 bar when idling at 1000 rpm.
and 90 Celcius. At 3000 rpm and higher the gauge sits between 5.5 - 6.0 - 6.3. I use half synthethic 10W40 (different brands). No leaks because all seals are new.
The engine crank has new bearings and the tolerances are by the book.
Cold start: no pedal. It takes about two seconds before oil pressure light fades and another second before the cauge moves.
A very light rattle can be heard before the pressure gets on. Under pressure, mechanical sounds are still there (maybe camshafts) but they
disappear completly when engine is warm.
I use only filters sent by the official dealer.
My car has a switch under the steering column wich
interrupts the ignition. So I turn the engine till oil light go's out. Then put the switch back and start. It helps to fill the system before forces are put into the bearings.

Regards

Hayo.
dave handa (Davehanda)
Intermediate Member
Username: Davehanda

Post Number: 1687
Registered: 5-2001
Posted on Wednesday, August 20, 2003 - 1:45 pm:   

Veglia
Paul Jeffery (Peajay)
Junior Member
Username: Peajay

Post Number: 120
Registered: 4-2002
Posted on Wednesday, August 20, 2003 - 1:35 pm:   

OK good advice, thanks Dave, is the sender a Bosch part ?
dave handa (Davehanda)
Intermediate Member
Username: Davehanda

Post Number: 1683
Registered: 5-2001
Posted on Wednesday, August 20, 2003 - 12:49 pm:   

Paul,
I would have to agree with Steve, the newest 328 is now 14yo and these senders do get weird with age. My previous 308 started reading oil temps that were high, a new sender fixed it right up. The senders are relatively inexpensive..try the Ferrari Owner's Site for the Ferrari UK link...

As a quick check, I suppose it would NOT be much trouble to add another direct ground to the oil pressure gauge (but I doubt it will fix your problem). Removal of the cluster is very easy. Place some towels across the steering wheel hub, then remove the indicator lights from each corner. Then remove the #2 Phillip head screws behind them. The cluster will pull right out. Rather than remove the steering wheel to get the cluster completely out, just tilt it slightly so you can reach behind....you will see the wires to the gauges quite clearly. Should be simple enough to splice in another ground wire and run it to a clean ground point.
Steve Magnusson (91tr)
Intermediate Member
Username: 91tr

Post Number: 2044
Registered: 1-2001
Posted on Wednesday, August 20, 2003 - 12:09 pm:   

Paul -- IME the oil pressure sender does show an "aging" effect that causes it to read lower with time. I think you could replace the oil pressure sender as a first step with no regrets and not much cost. If it still reads low then you'll need to dig deeper, but replacing the sender seems not uncommon.
Paul Jeffery (Peajay)
Junior Member
Username: Peajay

Post Number: 119
Registered: 4-2002
Posted on Wednesday, August 20, 2003 - 11:29 am:   

Kurt the car has 65 000 km so not too much. I will check the ground as you mentioned, does that mean I have to pull out the complete cluster ? Any idea if sender unit problems show symptoms like this ?
Kurt Kjelgaard (Kurtk328)
Junior Member
Username: Kurtk328

Post Number: 209
Registered: 3-2001
Posted on Wednesday, August 20, 2003 - 2:13 am:   

Paul, 1000 RPM - should be 1000 to 1100 acc. to books. Have the idle speed adjusted when warm. Acc. to your initial post you have 3 Bar at 1000 RPM - sounds normal.
After hard driving though, you will see the pressure drop below 3 Bar in idle - this is normal too.
4.5 Bar at normal driving seems at bit low, could be instrument, oil pressure transmitter, oil pressure regulator, electrical connection, worn engine (how many km's)?
I noticed on my car that when the lights are on, the instrument showed a higher reading - this has been discussed in an earlier thread.
Often the cure is cleaning and securing the grounding point for the instrument cluster.
This sits behind the central instrument housing.
Paul Jeffery (Peajay)
Junior Member
Username: Peajay

Post Number: 118
Registered: 4-2002
Posted on Tuesday, August 19, 2003 - 4:33 pm:   

Peter

I don't have much concern at cruise speed, but I would be very interested to hear what you have at idle and what speed gives that pressure. My idle speed drops about 100 rpm when hot and I suspect that makes quite a difference on the pressure. My oil temp. was 80C/175F
dave handa (Davehanda)
Intermediate Member
Username: Davehanda

Post Number: 1663
Registered: 5-2001
Posted on Tuesday, August 19, 2003 - 12:09 pm:   

Peter,
I had a 78 308 GTS, ran whatever brand of synthetic was on sale...no leaks, ever. I have run synthetics in every vehicle/motorcyle I have every owned in the last 16+ years, regardless of age, no leaks, no problems...the "synthetics cause leaks" thing is mostly wrong...IF you have a slight leak, it will likely be worse with a synthetic, but if the car is tight, no problems...Most old cars are, well, OLD, so they already leak a bit, and synthetic and I guess it could get worse...I would rather fix the leaks and run synthetics, they offer much better protection and lubrication, plain and simple.
Peter Barbin (Sophia)
New member
Username: Sophia

Post Number: 6
Registered: 8-2003
Posted on Tuesday, August 19, 2003 - 12:04 pm:   

Paul, I'm in a psi instrument world in my US 78 308GTS. So, I'm about 70 psi, full op temp of 170F around 3800rpm in cruise...I'll drive my car tomorrow, so I'll whip out the pen and pad and get some very accurate specs. My car has 28000mi reported on the odom.

I'm running Kendall GT1 20/50 Oil; this on the recommendation of Alfa of Tacoma-servicing Ferrari's for 25+ years...and on my own observations using Kendall in my old '77BMW R100RS motorcycle and my old VW Type IV Porsche.
This oil has performed well under the stresses of these air-cooled engines, consumption way down, etc.

Beware the switch to synthetics in the older "sealed" engines. You could get a leak monster!
Paul Jeffery (Peajay)
Junior Member
Username: Peajay

Post Number: 117
Registered: 4-2002
Posted on Tuesday, August 19, 2003 - 11:49 am:   

Kurt what is your idle speed ?
Kurt Kjelgaard (Kurtk328)
Junior Member
Username: Kurtk328

Post Number: 208
Registered: 3-2001
Posted on Tuesday, August 19, 2003 - 9:44 am:   

Mine is steady at 6 kg/cm2 (almost the same in Bar's) during normal driving.
Idle is around 3.
Book says normal is between 5.5 and 6.5 kg/cm2 (6000 RPM and 100 C oil temp I believe. I don't have the manual with me)
Paul Jeffery (Peajay)
Junior Member
Username: Peajay

Post Number: 116
Registered: 4-2002
Posted on Monday, August 18, 2003 - 12:22 pm:   

Peter

The car currently has a UFI filter installed which is as recommended by Ferrari, I don't know about the oil because I have not changed it myself yet, it does look nice and clean, but I will change to Castrol synthetic very soon. What pressure does your car run at for normal driving ?
Michael Ledderman (Mikey)
New member
Username: Mikey

Post Number: 3
Registered: 8-2003
Posted on Sunday, August 17, 2003 - 7:17 pm:   

Paul,

I feel based on your past post that it is your oil filter.

Swap it out with another UFI or a Balwain B253

Stay away from Fram.

Mike
Peter Barbin (Sophia)
New member
Username: Sophia

Post Number: 3
Registered: 8-2003
Posted on Sunday, August 17, 2003 - 6:22 pm:   

Peajay, What filter are you using out of curiousity? Also, what oil type/grade? My 78 308 exhibits basically the same indications. As to being a little overfull, the manual suggests checking the dipstick within 10 minutes or so of shutdown before the oilcooler drains into the sump...I did my first oil & filter change a few weeks ago, filling the system to spec. If I check the oil after an "over-night" sit, it reads high.

Admittedly, I'm one of those skeptics when it comes to oil-filter specs. That is, I spend the extra $ for the OEM filter, even from a dealer...In my years as a mechanic, sometimes the aftermarket filters cause problems. I do waiver from this when I can find filters from the OEM factory supplier, thus bypassing the dealer.
Paul Jeffery (Peajay)
Junior Member
Username: Peajay

Post Number: 115
Registered: 4-2002
Posted on Sunday, August 17, 2003 - 6:08 pm:   

Mike

I did notice that it took a few seconds for the oil light to go out and the gage to show a pressure. I have a UFI filter installed and I do have a new one ready to install and an oil change planned, so maybe that will help.
Michael Ledderman (Mikey)
New member
Username: Mikey

Post Number: 1
Registered: 8-2003
Posted on Sunday, August 17, 2003 - 5:48 pm:   

Paul,

It could also be a bad oil filter. Sometimes they collapse and give a low pressure reading. Change your oil filter to see if that helps

Mike
Paul Jeffery (Peajay)
Junior Member
Username: Peajay

Post Number: 114
Registered: 4-2002
Posted on Sunday, August 17, 2003 - 3:59 pm:   

I have my 328 back on the road after a cam belt change, all seems fine, no leaks etc. I did the belt job as soon as I got the car so didn't run it much, so I was surprised to see that when warm the idle oil pressure drops to about 2 bar (30 PSI) no rattles or oil light. At normal driving the pressure sits firmly at 4.5 bar, looks like it is regulated ? Anyway, the car runs fine with no unusual noises although the idle speed when warm seems a little low at about 850-900 rpm, if I push the rpm up to about 1000, I see the pressure goes up to about 3 bar. Is this normal behavior ? I noticed that the oil level is a little overfull also. Advice much appreciated as always.

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